CPCWiki - THE Amstrad CPC encyclopedia! - User contributions [en]

JavaCPC

2026-04-09T12:10:31Z

Eto: /* Web links */ removed dead links

[[File:javacpc.png|thumb|JavaCPC emulating a CPC6128]]
[[File:Javacpc_running_scratch.png|thumb|JavaCPC running an actual demo]]
[[File:Javacpc_debugger.png|thumb|The debugger in action]]
'''JavaCPC''' is a CPC emulator written in Java.
It is being developed by [[Devilmarkus]] and uses [[Executioner]]'s [[JEMU]] as base.

JavaCPC Desktop requires Java v1.6 or later; older versions also run under Java v1.5.

== Features ==
* Autotype
* Basic FDC-emulation
* Bilinear screen filtering (can be disabled)
* Emulates the [[CPC|Amstrad CPC]] 464, 664 and 6128
* [[CRTC]] 0/1 emulation
* [[Digiblaster]] emulation
* Direct export (Binary) / import of CPC files (BASIC, Binary)
* Drag and Drop
* Dynamic turbo
* Free selectable ROMs (OS and expansion ROMs)
* [[FutureOS]] support
* Green, monochrome and colour monitor emulation
* High accurate [[AY-3-8912]] emulation
* Integrated debugger with breakpoints and break instructions
* ROM emulation (0 up to 32!).
* [[SymbOS]] support
* Tape emulation, which supports WAV, CDT, TZX, CSW and MP3
* Text-printer
* Save current CPC screen as text
* WAV recorder
* YM-recorder and player!

== Planned features ==

* Light gun
* FDC improvements

== Running JavaCPC Desktop on OS X and Linux ==

Download the ZIP archive from http://cpc-live.com/data/index.php, then uncompress it and double click JavaCPC.jar in your file manager to run JavaCPC.

You could also create a shell script to start the program, e.g.:

#!/bin/sh
cd /usr/lib/javacpc
java -jar JavaCPC.jar -Xms512m

If you run Arch Linux, here is a [http://aur.archlinux.org/packages/javacpc/ JavaCPC AUR package].

Sound from the CPC can be a problem if the system is running PulseAudio (as most current Linux distos do). One possible workaround is simply killing the PulseAudio server before starting JavaCPC or prefixing the Java command with "pasuspender" to suspend PA. (For the latter approach, browsers or media players that currently use PA need to be closed first or suspending will not work.)

== Web links ==

* [http://sourceforge.net/projects/javacpc The Sourceforge project site for JavaCPC] (download, source code)

[[Category:4 MB RAM Software Support]]
[[Category:Digiblaster]]
[[Category:Emulator]]
[[Category:FutureOS]]

Connecting the CPC to a VGA monitor - CPC2VGA

2026-02-23T11:13:53Z

Eto: /* Open Source CPC2VGA PCB */

Most VGA monitors won't support the CPCs signal directly and require an [[LCD_monitor_and_LCD_TV_Solution_(RGB)#Converter_options|active converter/scan doubler]] but some monitors are accepting a 15.6kHz signal like provided by the CPC.

In the late 80s and 90s there were a couple of CRT multisync monitors like the NEC Multisync series. For modern LCD monitors the support of 15.6kHz is rare but there are a couple of monitors that are known to work well: https://15khz.miraheze.org/wiki/Main_Page

If you own such a monitor you can easily connect the VGA monitor to the CPC. For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

Unfortunately, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. The NEC LCD 1970NX, which is often referred to as the perfect monitor for Amigas or Atari STs would be an example. In those cases, an adapter, that splits c-sync into h-sync and v-sync would be required.

Don't trust sellers who claim their adapter would be able to split the signals without the need of external power. While they don't lie per sé they "forget" to tell you that this requires that the VGA monitor provides power on pin 9 - which not all of them do (e.g. again the NEC 1970). In this case you will have a simple passive adapter that does not split the signal and still requires that the monitor accepts C-sync.

See section below on how to build an adapter which is externally powered and definitely splits the signal.

== Open Source CPC2VGA PCB ==

A simple circuit based on the LM1881 to split the Composite Sync signal into H- and V-Sync could be this:

{|
|-
| [[File:CPC2VGAschematics.png|thumbnail|none|CPC2VGA LM1881 schematics]] || [[File:Cpc2vga-BOM.jpg|thumbnail|none|Parts used]]|| - [[File:Cpc2vga_plain.jpg|thumbnail|none|CPC2VGA - PCB fully built]]||
|}

* [[Media:Gerber CPC2VGA LM1881 240905.zip|Gerber Files]]

== Other solutions ==

If your VGA monitor does not support the 15.6kHz modes you will need an additional active adapter that adapts the frequency (scan doubler or scaler):

[[LCD monitor and LCD TV Solution (RGB)]]

[[Category:DIY| ]] [[Category:Hardware| ]]

File:Cpc2vga-BOM.jpg

2026-02-23T11:11:53Z

Eto:

CPC iRAM

2026-02-05T15:38:00Z

Eto: /* Compatibility */

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is the first [[Standard_Memory_Expansions|standard]] compatible, internal plug & play RAM expansion series for the CPC range of computer and provides up to 1MB of expanded RAM. All variations are open source, DIY friendly and sit in the CPU socket with no further cabling and no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far for the 6128 version.

The first revision of the 464 version has been found to be incompatible with the [[M4_Board|M4 Board]]. [https://github.com/etomuc/CPC464-iRAM1024/blob/main/README_rev1.md#modification-for-m4-incompatibility A patch has been published].

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== Available versions ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-640

''Note: Meanwhile a commercial product is available at Lotharek.pl which also claims to offer 640K and is even smaller, not much larger than the CPU socket itself. However not much information can be found except for the shop.''

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] support for 6128 compatibility
* alternatively without C3 support 576K or 1088K (one or two SRAMs fitted)
* easy to assemble, all through-hole components

Repository: https://github.com/etomuc/CPC464-iRAM1024

[[Category:Hardware]] [[Category:Memory expansions]] [[Category:DIY| ]]

CPC iRAM

2026-02-05T15:35:41Z

Eto:

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is the first [[Standard_Memory_Expansions|standard]] compatible, internal plug & play RAM expansion series for the CPC range of computer and provides up to 1MB of expanded RAM. All variations are open source, DIY friendly and sit in the CPU socket with no further cabling and no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far for the 6128 version.

The first revision of the 464 version has been found to be incompatible with the [[M4_Board|M4 Board]]. [https://github.com/etomuc/CPC464-iRAM1024?tab=readme-ov-file#modification-for-m4-incompatibility A patch has been published].

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== Available versions ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-640

''Note: Meanwhile a commercial product is available at Lotharek.pl which also claims to offer 640K and is even smaller, not much larger than the CPU socket itself. However not much information can be found except for the shop.''

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] support for 6128 compatibility
* alternatively without C3 support 576K or 1088K (one or two SRAMs fitted)
* easy to assemble, all through-hole components

Repository: https://github.com/etomuc/CPC464-iRAM1024

[[Category:Hardware]] [[Category:Memory expansions]] [[Category:DIY| ]]

CPC iRAM

2026-01-06T12:58:07Z

Eto: /* CPC 6128 - iRAM/1088 */

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is the first [[Standard_Memory_Expansions|standard]] compatible, internal plug & play RAM expansion series for the CPC range of computer and provides up to 1MB of expanded RAM. All variations are open source, DIY friendly and sit in the CPU socket with no further cabling and no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far for the 6128 version.

The first revision of the 464 version has been found to be incompatible with the [[M4_Board|M4 Board]]. [https://github.com/etomuc/CPC464-iRAM1024?tab=readme-ov-file#modification-for-m4-incompatibility A patch has been published] and is currently tested. Further revisions will include the patch once tests have been successful.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== Available versions ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-640

''Note: Meanwhile a commercial product is available at Lotharek.pl which also claims to offer 640K and is even smaller, not much larger than the CPU socket itself. However not much information can be found except for the shop.''

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] support for 6128 compatibility
* alternatively without C3 support 576K or 1088K (one or two SRAMs fitted)
* easy to assemble, all through-hole components

Repository: https://github.com/etomuc/CPC464-iRAM1024

[[Category:Hardware]] [[Category:Memory expansions]] [[Category:DIY| ]]

CPC iRAM

2026-01-06T12:47:47Z

Eto:

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is the first [[Standard_Memory_Expansions|standard]] compatible, internal plug & play RAM expansion series for the CPC range of computer and provides up to 1MB of expanded RAM. All variations are open source, DIY friendly and sit in the CPU socket with no further cabling and no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far for the 6128 version.

The first revision of the 464 version has been found to be incompatible with the [[M4_Board|M4 Board]]. [https://github.com/etomuc/CPC464-iRAM1024?tab=readme-ov-file#modification-for-m4-incompatibility A patch has been published] and is currently tested. Further revisions will include the patch once tests have been successful.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== Available versions ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-640

''Note: Meanwhile a commercial product is available at Lotharek.pl which also claims to offer 640K and is even smaller, not much larger than the CPU socket itself. However not much information can be found except for the shop.''

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Repository: https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] support for 6128 compatibility
* alternatively without C3 support 576K or 1088K (one or two SRAMs fitted)
* easy to assemble, all through-hole components

Repository: https://github.com/etomuc/CPC464-iRAM1024

[[Category:Hardware]] [[Category:Memory expansions]] [[Category:DIY| ]]

CPC iRAM

2026-01-06T12:28:08Z

Eto: /* released */

CPC iRAM

2026-01-06T12:25:51Z

Eto: /* Compatibility */

CPC iRAM

2026-01-06T12:24:53Z

Eto: /* Compatibility */

CPC iRAM

2026-01-06T09:36:28Z

Eto:

CPC iRAM

2026-01-06T09:28:23Z

Eto: /* CPC 464/664 - iRAM/1024 */

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] support for 6128 compatibility
* alternatively without C3 support 576K or 1088K (one or two SRAMs fitted)
* easy to assemble, all through-hole components

Status: Released - see https://github.com/etomuc/CPC464-iRAM1024

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

User:Eto

2025-12-22T10:00:26Z

Eto: Created page with "== Hardware Projects == * iRAM - internal RAM for the CPC * GX4000/Plus flexible multi-cartridge PCB * CPC_6320_/_CPC_6512_-_interna..."

== Hardware Projects ==

* [[CPC_iRAM|iRAM]] - internal RAM for the CPC
* [[Multi_Cartridge_8_ROMs|GX4000/Plus flexible multi-cartridge]] PCB
* [[CPC_6320_/_CPC_6512_-_internal_320K_/_512K_for_CPC_6128|CPC6512]] - internal DRAM replacement for the CPC 6128 to support 512K of RAM
* [https://github.com/etomuc/CPC-AY-3-8910-to-8912-adapter AY-3-8910 to AY-3-8912 adapter] - adapter to use the AY-3-8910 adapter in the CPC instead of the expensive 8912 variant
* [[Connecting_the_CPC_to_a_VGA_monitor_-_CPC2VGA|CPC2VGA]] - adapter to connect the CPC to a 15kHz capable VGA monitor including active C-Sync separator

== Software ==

* [https://blue-genie.itch.io/the-enchanted-stones-of-cameronne The enchanted stones of Cameronne] - Ishido-style game

CPC iRAM

2025-12-22T09:01:49Z

Eto:

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This can be useful for external feature-expansions that also provide a RAM expansion and usually cannot be used in parallel with other (external) RAM expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the ULIFACs RAM with ROM slots. Now with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Released - see https://github.com/etomuc/CPC464-iRAM1024

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

CPC iRAM

2025-12-22T08:59:40Z

Eto:

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

No incompatibilities have been reported so far.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

External memory expansions will be ignored once the iRAM is installed. This is particularly helpful for external feature-expansions that also provide a RAM expansion and cannot be used in parallel with other external expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the expanded RAM with ROM slots - but with the iRAM installed the CPC still has access to the full RAM provided by the iRAM. If needed a disable switch can optionally be connected to disable the internal iRAM from outside the CPC without removing the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Released - see https://github.com/etomuc/CPC464-iRAM1024

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

GX4000 cartridge

2025-12-15T23:25:22Z

Eto: /* Misc */

[[Image:Burning Rubber - cara A.jpg|right|thumb|250px|GX4000 Burnin' Rubber cartridge]]

A cartridge system was introduced with the launch of the [[Plus]] and GX4000 series. This enabled developers to distribute games via cartridges on the new Amstrad. The cartridges are protected with the [[ACID]] chip.

== EPROMs ==

All known manufactured cartridges contain EPROMs (rather than PROMs or ROMs). The cartridges can be fitted with different EPROMs in range of 32kb through 512kb, but only 128kb to 256kb versions are known to have been produced. The cartridge PCBs typically include six [[LK Links]] to match the PCB to the EPROM pin-outs:
VCC ---LK1--- EPROM.A18 ---LK2--- CA18
VCC ---LK3--- EPROM.A17 ---LK4--- CA17
VCC ---LK5--- EPROM.A15 ---LK6--- CA15
Usually the following LKs should be installed:
(----- EPROM -----) (------------------------ Links installed -------------------------)
Type Pins Size A15 A17 A18
27C256 28 32K LK5 (A15=VCC=High) LK3 (A17=VCC=Supply) N/A
27C512 28 64K LK6 (A15=A15=Address) LK3 (A17=VCC=Supply) N/A
27C1001 32 128K LK6 (A15=A15=Address) N/A LK1 (A18=VCC=/PGM)
27C2001 32 256K LK6 (A15=A15=Address) LK4 (A17=A17=Address) LK1 (A18=VCC=/PGM)
27C4001 32 512K LK6 (A15=A15=Address) LK4 (A17=A17=Address) LK2 (A18=A18=Address)
Some cartridge PCBs don't have any LKs installed, instead, the etched circuit has hardwired connections between some of them. One could scratch them off, and then use the LK soldering points to reconfigure the board for eproms of other size.

== Protection ==

The EPROMs aren't encrypted, making it very easy to dump their content, or to replace them by other EPROMs. However, all cartridges must contain an [[ACID]] chip, otherwise the [[Plus]]/GX4000 refuses to work, meaning that unlicensed third-party developers couldn't produce cartridges without buying the [[ACID]] hardware from Amstrad.

== Pictures ==

<gallery caption="2700-023P-1 (with hardwired LK1 and LK6, and single-sided soldering points)">
Image:Cartridge-2700-023P-1-Components.jpg|Components
Image:BurningRubberGX4000versionPCB.jpg|Components installed
Image:Cartridge-2700-023P-1-Top.jpg|Component Side
Image:Cartridge-2700-023P-1-Bottom.jpg|Solder Side
</gallery>

<gallery caption="PT-NO-Z90903-MS0201A (with custom LKs, and single-sided soldering points)">
Image:Cartridge-PT-NO-Z90903-MS0201A-Cartridge.jpg|Cartridge
Image:Cartridge-PT-NO-Z90903-MS0201A-Installed.jpg|Components installed
Image:Cartridge-PT-NO-Z90903-MS0201A-Bottom.jpg|Solder Side
</gallery>

<gallery caption="PT-NO-Z90903-MC0121A (with custom LKs, and double-sided soldering points)">
Image:Inside GX4000 cart 1 unrotated.jpg|Components installed
Image:Inside GX4000 cart 2.jpg|Solder Side
Image:Burning Rubber - cara A.jpg|Case Front (Component Side)
Image:Burning Rubber - cara B.jpg|Case Back (Solder Side)
Image:AMSTRAD CPC CARTRIDGE PT NO Z90903 B PARTSSIDE WITHOUT PARTS PCB SCAN ATV.jpg|Component Side (scan by ArcadeTV)
Image:AMSTRAD CPC CARTRIDGE PT NO Z90903 B SOLDERSIDE WITHOUT PARTS PCB SCAN ATV.jpg|Back side (scan by ArcadeTV)
</gallery>

<gallery caption="Spanish cartridge without text-layer on PCB (otherwise same as 2700-023P-1)">
File:Dragon CPC Plus System Cartridge PC Spanish.jpg|Components installed
</gallery>

<gallery caption="AMSTRO1 (with hardwired LK1 and LK6, and double-sided soldering points)">
File:Cart PCB AMSTRO1 top.jpg|Component Side
File:Cart PCB AMSTRO1 bottom.jpg|Solder Side
</gallery>

<gallery caption="Cartridge Slot">
File:GX4000 Top.jpg|GX4000 with top-loading cartridge slot
File:CPC464Plus LeftSide Nighfallcrew.jpg|CPC Plus with side-loading cartridge slot
</gallery>

== Demonstration System ==

Amstrad released a Demonstration system for his retailer in order to show GX4000 games: the [[Amstrad CSD]] (Cartridge Software Demonstrator).

It was a 464 [[Plus]] motherboard, with an extra "daughter board" allowing the insertion of 12 games cartridges, plus an extra special cartridge acting as an OS.

<gallery caption="Some photos of Amstrad Expo 90">
Image:csdscreen1.jpg
Image:csdscreen2.jpg
Image:csdface.jpg
Image:csddaughter.jpg
</gallery>

Courtesy of Amstrad.cpc.free.fr

More informations at the [[Amstrad CSD]] page.

== Pin-Outs ==

* [[Connector:Cartridge Slot (CPC Plus only)|Cartridge Slot Pin-Outs]]

== Misc ==

* [[RAM7]], a French hardware developer, created a device to hack [[RAM7 Cartridge Hacker|CPC Plus cartridges]].
* [[CPC GX4000-Multi EPROM Cartridge]]
* [[Multi Cartridge 8 ROMs|DIY Multi Cartridge for up to 8 ROMs]]
* [[Converted GX4000 Software]]

==Links==

* [http://www.vieuzordiland.fr/index.php?option=com_content&task=view&id=23&Itemid=34 Vieuxzordiland's page on replacing EPROMs. In French]
* [http://amstrad.cpc.free.fr/article.php?sid=16 Link to the French article on the Demonstration System]

[[Category:Hardware]][[Category:Cartridges| ]][[Category:DATA Storage]]
[[Category:CPC Internal Components]][[Category:CPC History]][[Category:CPC Plus]]

Writepin

2025-11-27T12:07:58Z

Eto: added link to Noels retrolab video on how to make a pin replacement

Help, I changed the drive-belt and now my disk drive is suddenly read-only?

This is probably one of the most frequently asked questions here in the forum, so I thought I'd make a short guide to address it...

Chances are, you've lost the write-pin while you were changing the belt. It's a small metal pin that senses the position of the write-protection tab on the inserted disk and if it's missing all disks will seem to be write-protected to the computer.

But before you go crawling around aimlessly on that patterned carpet, here's what you are actually looking for:

[[image:Pin.JPG|600px|center]]

Yes, it's small. If you do find it, this is where it needs to go. It simply drops into the hole. If no disc is inserted at the time, it should go all the way in until the head is lying against the aluminium frame:

[[image:PinPos.JPG|600px|center]]

If you really lost your pin, check out the link at the end of this page.

However, this might not be your problem. There are several versions of the Amstrad 3in drive and not all of them used a physical pin, some used optical sensors. So how do you tell if your drive had a pin in the first place?
If your drives PCB has a black sensor like this one:

[[image:Optical1.JPG|600px|center]]

Or a plexiglass sensor like this one:

[[image:Optical2.JPG|600px|center]]

Then stop crawling around on your hands and knees like an idiot, your drive never had a pin, so you haven't lost it.

If however, your PCB has switch contacts that look like this:

[[image:PinSwitch.JPG|600px|center]]

Then keep looking, you really have lost it. If you still can't find it, then your only option is to make a new one. This is what you'll need to make:

[[image:Writepin.png|600px|center]]

This should be quite easy to make from a small nail, but you will need to ensure that the sides of the shaft are quite smooth so that it freely moves as intended.

Bryce.

== If you lost the pin ==

If you really lost the pin you can make a replacement from a simple paper clip. Noel's Retrolab has documented the process in this video: https://www.youtube.com/watch?v=3gX1cnZR6nM&t=500s

[[Category:DIY]]

CPC iRAM

2025-11-08T13:41:30Z

Eto:

[[File:Iram640.jpeg|thumbnail|iRAM/640 for the CPC 6128]]
[[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464/664]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

So far no incompatibilities have been reported.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

Unlike other RAM expansions the iRAM can be used in parallel to an external RAM expansion. The iRAM has priority over external RAM expansions and only requests above the iRAM memory limit will be passed to an external RAM expansion. External memory expansions that are smaller than the iRAM will be ignored. This is particularly helpful for external feature-expansions that also provide a RAM expansion. Those expansions usually cannot be connected in parallel to another (bigger) RAM expansion. E.g. DDI-5/6, ULIFAC and Pico CPC limit the CPC to the RAM provided by those expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the expanded RAM with ROM slots - but with the iRAM installed the CPC still has access to the full RAM provided by the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Released - see https://github.com/etomuc/CPC464-iRAM1024

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

File:Iram1024.jpg

2025-11-08T13:36:35Z

Eto:

Albireo

2025-11-05T13:23:56Z

Eto: /* List of compatible mouses */

Albireo is an expansion for the Amstrad CPC computers (all models). Its main goal is to provide reliable, fast, cheap and large storage, which it achieves by using a MicroSD card. But the board has a lot of features packed in:
* USB host port, allowing to connect USB mass storage, mouse, and other USB peripherals
* USB device port, allowing to link the CPC to a modern computer with maximal link speed (faster than the z80 can handle, and with on-board buffer and hardware flow control).

The interface is based on the WCH CH376 chip and allows access to USB mass storage and other USB devices on CPC.

The CH376 chip implements FAT32 in hardware, which means no filesystem driver is needed on the CPC side. This makes it very easy to use the interface with a microSD card, USB stick or hard drive and access files on the FAT32 partition directly, without using a lot of CPU power or memory on the CPC.

It also implements the lower level aspects of USB, making it relatively easy to write drivers for other USB devices (mouse, joystick, ...). It is simple enough that the mouse driver was initially written completely in BASIC.

The Albireo USB port can drive any USB peripheral, including any standard USB mouse. It is no more needed to dig out a PS/2 compatible mouse for your [[Symbiface II]], or even worse, an Atari/Amiga one for the [[MultiPlay]].

'''USB is the solution we need to free ourselves from all the weird, ad-hoc, incompatible, expensive, hard to find CPC hardware extensions that we all suffer from. And it opens up the CPC world to countless existing peripherals.'''

 

== General ==

=== What's in it? ===
* SD and SDHC card mass storage support with fast (6 MHz) SPI link with the SD card. Hardware FAT32 support for easy file access. Raw sector access also possible for homegrown file-systems and other advanced applications.
* USB host support with built in mass storage driver, also with FAT32 and direct sector access.
* Generic USB host with direct control of USB endpoints, for connecting other kinds of USB devices.
* High-speed (1.5 Mbaud) serial link with built-in USB interface for linking with other computers for fast data exchange. Includes flow control, 16 byte FIFO on CPC side, and 512 byte FIFO on remote side, allowing fast buffered and interrupt-driven operation.
* Software configurable interrupt routing to either [[NMI]] or INT, or interrupt masking. Multiplexing of several interrupt sources: USB host controller, UART, remotely triggered, and CRTC CURSOR signal interrupts are gathered and easily accessible from a single interrupt status register.

=== How does it work? ===
* There are two main devices: the CH376 handles the USB host and SD card side of things, and is accessed at FE80 (data) and FE81 (command/status). The communication side is handled by a SC16C650B, mapped at FEB0-FEB7. This is similar to the chip used on most PC hardware and some Amiga expansions like the SilverSurfer.
* There is an FT230X chip to convert the UART to USB for connecting with a modern PC (standard serial ports are not that common anymore, and they wouldn't be fast enough anyway). The FT230X also generates 12MHz and 48MHz clocks for the two other chips.
* The 16C650 "modem control" lines are connected to various things (CH376 interrupt, FT230X general IO pin for remote control) and turns them into interrupts.

=== What is it useful for? ===
* Use both USB mass storage devices and/or USB mice in [[SymbOS]] with one or two Albireos, which can be connected at the same time
* Access mass storage devices with [[UniDOS]]; use the USB key or SD card directly from BASIC and well-behaving apps (which support extra disk ROMs and a C drive); load games and tools from the mass storage media

 

== Board revisions ==

The hardware went through multiple iterations before reaching final state. Each version identifies itself on the USB link and the version should be visible in Windows device manager or lsusb on Linux.

=== Initial prototypes ===

The first prototype was an hand-wired one. There were some changes to I/O ports used since then, so it is not usable anymore.

=== Version 0.9 ===

The first 5 boards were manufactured with an early PCB design, which required some wire-patches to get things working. With the wire-patches, this version behaves the same as 1.0.

=== Version 1.0 ===

About 20 boards were shipped with version 1.0. Unfortunately, as people started to write software using it it turned out that the serial port chip has compatibility problems with the z80 timings. As a result, this version of the board can use the serial port only with the FIFO disabled, which makes it impossible to reach high baudrates. The board is still perfectly usable if you are interested only in the microSD and USB host port.

=== Version 1.1 ===

This version of the board replaces the serial chip with a slightly different one. The board still reads "v1.0" as it is the same PCB, only the chip used has changed.

You can identify your board from the info it sends on the USB device port, or by checking the serial chip (square chip on the back of the board).
Version 1.0 uses a TI TL16C550D chip. Version 1.1 uses a NXP SC16C650B chip.

=== Version 2.0 ===

Like the previous version, it provides one USB host port and one µSD slot with built-in support for mass storage and FAT filesystem. However, please note '''serial port has been removed'''. It is fully compatible (same port address). Of course, nothing is mapped on serial port addresses.

All interrupts on the board were handled by the SC16C650B chip. It is unclear how they are treated in version 2.0.

This Albireo version has solder jumpers on bottom side (JP2 & JP3) to change the I/O address from the default &FE80/81 to &FE40/41. You need a cutter and a bit soldering to do this change, though. This allows to plug two Albireo cards simultaneously. The latest Albireo and Unidos ROMs together can already handle this (yay!).

This will allow to, for example, use one board for mass storage, and the other to connect various USB devices: mouse, MIDI controller, printer, whatever you need (as long as you find someone to write a driver).

Strictly speaking, it might be possible to handle both a mouse and a USB stick on one card by using a USB hub. But this has to be coded and tested, the CH376 documentation is unclear on this topic. [https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/albireo-usbsd-interface-for-cpc-new-version-without-serial/msg248489/#msg248489 Source]

[[File:Albireo 2.0 top.jpg|500px]] [[File:Albireo 2.0 bottom.jpg|500px]]

 

== Hardware ==

=== I/O ports ===

The decoding is clean, this means there aren't any mirror ports or undecoded address bits. Just the addresses listed below are used.

The addresses are in the I/O range, which means you access them with the OUT and IN instructions. They are not memory mapped.

==== CH376 registers ====

* FE80: "DATA" port (read/write)
* FE81: "COMMAND" (write) and "STATUS" (read) port

==== SC16C650B registers ====

Some of the registers are sharing the same address. A register bit (DLAB) is used to switch between the two groups.
<tt>
{|
|-
! Address !! DLAB !! Description
|-
| FEB0 || 0 || RBR/THR: RX buffer (read), TX buffer (write)
|-
| FEB1 || 0|| IER: Interrupt enable
|-
| FEB0 || 1|| DLL: Divisor latch LSB
|-
| FEB1 || 1|| DLM: Divisor latch MSB
|-
| FEB2 || || IIR/FCR: Interrupt status (read), FIFO control (write)
|-
| FEB3 || || LCR: Line control
|-
| FEB4 || || MCR: Modem control
|-
| FEB5 || || LSR: Line status
|-
| FEB6 || || MSR: Modem status
|-
| FEB7 || || SCR: Scratch register
|}</tt>

=== DIP switches ===
The board holds 4 DIP switches for configuration. From top to bottom:

==== S1 - CH376 interrupt enable ====

* When this switch is ON, the usb controller is allowed to generate interrupts to signal the CPC when it is done performing an operation.
* When this switch is OFF, the usb controller is not allowed to generate interrupts. The CPC must then poll the CH376 STATUS register to know wether the operation is finished.

==== S2 - CH376 reset enable====

* When this switch is ON, the CH376 will be reset at the same time as the CPC (hardware reset only).
* When this switch is OFF, the CH376 will not be reset, and the CPC must initialize it using the reset command (software reset). In this case, the CH376 internal buffer may be used to store reset resident data (but I don't know if this is of any practical use, yet).

==== S3 - Remote reset enable ====

* When this switch is ON, the DTR signal from the remote side of the serial link is connected to the CPC reset. This means that the remote side computer can trigger the CPC reset by toggling that line.
* When the switch is OFF, such reset is not allowed and the CPC is safe.

==== S4 - Remote interrupt enable ====

* When this switch is ON, the DTR signal from the remote side of the serial link is plugged to the DSR line of the UART controller. It then generates an interrupt which the CPC can process.

 

== Software supporting the Albireo ==
* [[UniDOS]] ([[AMSDOS]] compatible and modular DOS; see [https://unidos.cpcscene.net UniDOS official website])
* [[SymbOS]] (both USB mass storage devices and USB mouse; supports two Albireos connected at the same time)
* [[Arkos_Tracker]] 2 (use the CPC AY chip through the USB serial port)
* [[FutureOS]] (USB mouse support)
* [[HDCPM]] (Support booting and running CP/M Plus from SD card)
* [[AlbiDOS]] **'''deprecated''', replaced by [[UniDOS]]** ([[AMSDOS]] compatible DOS driver; see [https://framagit.org/shinra/albireo/albireodos/-/wikis/home AlbiDOS documentation])

 

== List of compatible mice ==

The mouse can be used in 2 modes:
* "boot mode" is a simplified mode which is designed for use in PC BIOSes. It removes some of the complexity of HID. The drawback is, it supports only 3 buttons and 2 movement axes. Basically, that means no mouse wheel.
* standard ("report") mode is more complex, and there may be more compatibility problems with different mice.

=== Whitelist ===
The following USB mice work seamlessly with the Albireo in [[SymbOS]].

Legacy mice (used only):
* Genius DX-150X (GM-150028)
* Logitech M105
* Microsoft 3902C693

Still available (11/2025):
* Cherry MC1000
* Logitech M100
* Logitech B100

=== Blacklist ===
This list contains mice that only have a maximum of three buttons and a scroll wheel, but still don't work with the standard Albireo drivers. More complex gaming mice, etc., are not listed, as they would require a more complex driver anyway.
* Hewlett Packard HP 100

 

== Links ==
*[https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/albireo-usbsdserial-interface-for-cpc/ Albireo] [https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/albireo-usbsd-interface-for-cpc-new-version-without-serial/ Albireo 2.0] Topics on CPCWiki forum
*[[Media:Albireo1.0 schematics.pdf|Albireo KiCad schematics]]
*[https://framagit.org/shinra/albireo Albireo project] [https://framagit.org/offset/albireo-acepansion Albireo ACEpansion] on Framagit
*[https://pulkomandy.github.io/shinra.github.io/albireo.html Albireo - Programmer's manual]
*[[Media:Ch376ds1.pdf|CH376 datasheet]] [[Media:CH376DS2.PDF|CH376 auxiliary commands]] USB flash drive and SD card controller
*[[Media:CH372DS1.PDF|CH372 datasheet]] [[Media:CH372DS2.PDF|CH372 auxiliary commands]] USB device mode
*[[Media:Usb-in-a-nutshell.pdf|USB in a Nutshell]] Making Sense of the USB Standard
*[https://wiki.osdev.org/USB_Human_Interface_Devices USB Human Interface Devices] on OSDev wiki
*[https://www.nxp.com/docs/en/data-sheet/SC16C650B.pdf SC16C650B datasheet] UART

 

[[Category:DATA Storage]]
[[Category:Peripherals]]

Revision

2025-10-27T12:21:43Z

Eto: typo

'''Revision''' is an annual international Demoparty set in '''Saarbrücken''' in Germany.

Actually one of the biggest European Demoparty (if not THE biggest). And has many in common with a mundane Rave-Party.

'''Amstrad''' Productions were released in the Oldskool compositions during the 2010s era and would often be ranked on the podium, and a growing community of Amstrad users would regularly attend the event, be it to release something or just enjoy some Curry-Wurst and drink a few WeissBier.

== Timeline and Releases ==

==== 2011 ====

==== 2012 ====

* '''[[Wake Up!]]''' by [[Benediction]] & sector one : Ranked '''3rd''' in oldskool demo
* '''[[Stop that Nyan cat!]]''' by [[Benediction]] & hooy-program : Ranked '''3rd''' in oldskool intro
* The full '''Oldskool Demo compo 2012''' : check at 24:53.
{{#ev:youtube|-dYo1p0YSfk|480}}

==== 2013 ====

* '''[[Still Rising]]''' by [[Vanity]] : ranked '''2nd''' in oldskool demo
* The full '''Oldskool Demo compo 2013''' : check at 33:17.
{{#ev:youtube|qjx2IArwz1Q|480}}

==== 2014 ====

* '''[[Breaking Baud]]''' by crtc & 3ln : : ranked '''2nd''' in oldskool demo
* The full '''Oldskool Demo compo 2014''' : check at 13:58.
{{#ev:youtube|G8sxnxnAyH0|480}}

==== 2015 ====

* ''only beers and wurst.''

==== 2016 ====

* ''long time not seen, Amstrad.''

==== 2017 ====

This year's Oldskool Demo compo was literally stolen by the massively acclaimed [http://www.pouet.net/prod.php?which=69648 Overdrive 2], by TITAN on Sega MegaDrive, and the general level in the Oldskool compo was judged impressive by many commenters and deemed a huge highlight of the whole event, with awesome demos on [http://www.pouet.net/prod.php?which=69666 Atari VCS2600], [http://www.pouet.net/prod.php?which=69665 AppleIIgs] or [http://www.pouet.net/prod.php?which=69649 Atari Lynx] as well. Still an Amstrad Demo managed to be on the top podium despite a brutally fierce competition. The Live Twitch hosts were litterally rendered speechless after the Amstrad CPC performance that followed an already impressive Atari VCS 2600, they provided many things on screen judged impossible on these formats. Then Sega MegaDrive's entrance with its massive work in tunes and graphics finished to impress everyones and could also have raped the whole Amiga compo as well.

* '''[[Logon's run - 3D meets the aging bits]]''' by [[Overflow]] from logon system : ranked '''2nd''' in Oldskool Demo
* '''[[Wunderbar]]''' by [[Benediction]] & arkos : ranked '''4th''' in oldskool intro
<gallery>
Image:Big Capture01260.png|Amstradists.
Image:Img 0716-5211316.jpg|Amstradists.
Image:Img 5461-52191ba.jpg|two CPCs.
Image:Img 5163-5219195.jpg|one CPC.
Image:Img 6301-5219182.jpg|Overflow : "seriously I won something?"
Image:Img 6303-5219188.jpg|Overflow cashing some well deserved prizes.
</gallery>
* The full '''Oldskool Demo compo 2017''' : check at 10:50.
{{#ev:youtube|veWqxkTFs5w|480}}
* http://www.pouet.net/party.php?which=1550&when=2017

==== 2018 ====

The '''Revision2018''' saw a new step in Amstrad entries, participation and results. 2 entries in oldskool graphics, 2 entries in oldskool demo and 1 entrie in oldskool intro, with a final total of '''3 prizes'''.

* '''[[phX]]''' by [[Condense]] : ranked '''2nd''' in Oldskool Demo.
* '''[[Onescreen Colonies]]''' by [[Vanity]] : ranked '''4th''' in Oldskool Demo.

* '''[[Isometrikum]]''' by [[Vanity]] : ranked '''1st''' in Oldskool Intro.

* '''Smile !''' by [[Beb]]/Vanity: ranked '''3rd''' in Oldskool Graphics.
* '''Inversio_8102''' by [[CeD]]/Condense: ranked '''4th''' in Oldskool Graphics.

<gallery>
Image:C5fb.160277.png|'''Inversio_8102''' by CeD/Condense.
Image:D181.160254.png|'''Smile!''' by Beb/Vanity.
Image:CeD NoRecess Longshot TotO Overflow.JPG|Condense + LogonSystem = TotO
Image:Longshot BSC Overflow.jpg|Longshot, BSC, Overflow.
Image:NoRecess Factor6 CeD 2.jpg|NoRecess, Factor6, CeD from Condense.
Image:Toms Eliot Offset TotO HiddenCeD NoRecess Beb Krusty Hicks Zik.JPG|A huge pile of Amstradsits.
</gallery>

** The full '''Oldskool Demo compo 2018'''. Check at '''5:35''' (Onescreen Colonies) and '''25:20''' (phX)
{{#ev:youtube|_T5rzMpRISU|480}}

** You can check the '''[http://memoryfull.net/party.php?id=223 Memory Full page]''' ,'''[http://www.pouet.net/party.php?which=1550&when=2018 POUËT's page]''' and '''[https://demozoo.org/parties/3537/ Demozoo's page]''' for more infos on the '''Revision2018''' compos, prods and results.

==== 2019 ====

There were 4 Amstrad CPC productions this year. Also Pinball Dreams could be played at the Amstrad user's corner.
The Third Kind by Vanity managed to be 3rd in its category being the only CPC production's podium this year.

* Oldskool Demo : '''[[Gloire à Piou !]]''' by '''[[Overlanders]]'''.
Ranked 11th/15.

* Oldskool Demo : '''[[Octopus Pocus]]''' by '''[[Pulpo Corrosivo]]'''.
Ranked 6th/15.

* Oldskool Graphics : '''Brutal Deluxe''', Amstrad CPC Graphics by '''[[Beb]]''' from '''[[Vanity]]'''.
Ranked 6th/13

* Oldskool 4k intro : '''[[The Third Kind]]''' by '''[[Vanity]]'''.
Ranked '''3rd'''/10 '''Bronze Winner'''.

<gallery>
Image:Brutaldeluxebeb1.png|'''Brutal Deluxe''' by Beb
Image:00081055.png|'''Third Kind''' by Vanity
Image:Octopuspocus1.png|'''Octopus Pocus''' by Pulpo Corrosivo
</gallery>

** OldSkool Revision 2019 compo video link :
https://www.youtube.com/watch?v=vZnCYJXUaaw

==== 2020 ====

The Revision 2020 edition was marked by covid-19 crisis world event. It was a remote and streamed online Twitch event, which is better than nothing and the pinnacle of Sofa-Scene. This edition saw 2 Amstrad CPC productions being prized.

* Oldskool Graphics : '''Killing Oldschool''', Amstrad CPC Graphics by '''[[Beb]]''' from '''[[Vanity]]'''.
Ranked 5th/12

* Oldskool 4k intro : '''[[Square Roots]]''' by '''[[Vanity]]'''.
Ranked 1st, Gold Winner.

* Oldskool 4k intro : '''[[Daymo of the Tentacle]]''' by '''[[Arkos]]''' and '''[[Praline]]''' and '''[[Pulpo Corrosivo]]'''.
Ranked 3rd / 9, Bronze Winner.

<gallery>
Image:Square biroute.png|'''Square Roots''' by Vanity
Image:Daymo of the tante encule.png|'''Daymo of the Tentacle''' by Pulpo Corrosivo
</gallery>

==== 2021 ====

Again a "SOFASCENE" remote edition because of Covid-19 crisis. Featured a twitch ban/strike for the Revision party twitch channel. Oldskool Demo category had 15 entries and 1 Amstrad entry that won 2nd place (Silver medal). No other Amstrad entry this year. Rexbeng made graphics for a C64 game though (Moonspire 2, ranked 3rd).

* Oldskool Demo : '''[[Can Robots Take Control?]] (CRTC)''' by '''[[Benediction]]''' & '''[[Arkos]]'''.
Ranked 2nd/15, Silver Winner.

<gallery>
Image:00088554.gif|'''Can Robots Take Control?''' by Benediction
</gallery>

==== 2022 ====

Online event this year.

* Oldskool Demo :
11. '''Swingin'''' (Bug Powell + AsT)

* Oldskool 4k intro :
5. '''Open Space''' (Vanity)
8. '''Pixel Free''' (Plissken)

==== 2023 ====

At least 13 Amstrad Sceners were there.

* Oldskool Graphics:
15. '''Final Strike''' (Beb)

* Oldskool 4k intro :
4. '''Checkmate''' (Pulpo Corrosivo)

6. '''Emotion Trouble''' (Madram)

==== 2024 ====

At least 11 Amstrad Sceners attended the party.

* Game
3. '''Hypernoid Zero''' (Bitplane Technomantes)

* Oldskool 4K Intro
4. '''J'ai Pé-Télécran''' (Benediction + Dentifrice + Arkos)

* Oldskool Demo
1. '''Ghost NOP''' (Pulpo Corrosivo + Futurs')

6. '''Come Join Us''' (Benediction + Shinra)

* Oldskool Graphics
8. '''Roland and Grou''' (Beb / Vanity)

9. '''1984-2024: Rise of a new Shah''' (rexbeng)

==== 2025 ====

At least 11 Amstrad Sceners were seen drunk there...

* Oldskool 4K Intro
2. '''4deKades''' (Creative People for CPC)

* Oldskool Demo
5. '''3DManiaks2''' (Impact)

== Links ==

* Official Website (2017) : https://2017.revision-party.net/

* '''Pouët''' : http://www.pouet.net/party.php?which=1550&when=2017

* '''Memory Full''' website covers some Revisions: http://memoryfull.net/events.php

* '''YOUTUBE channel''' covering the event : https://www.youtube.com/user/RevisionParty/videos

* '''TWITCH channel''' : https://www.twitch.tv/revisionparty/videos/all

[[Category:CPC_events]][[Category:Demo Parties]]

Gotek

2025-10-23T22:49:38Z

Eto: /* Gotek mod */

[[File:Gotek standard.jpg|thumb|right|Standard Gotek drive]]
[[File:Custom Gotek drive.jpg|thumb|right|Custom Gotek drive by [[Rodrik Studio]]]]
[[File:Gotek external.jpg|thumb|External GOTEK for a Schneider CPC 6128 with Centronics cable, 3D printed top cover and splitter cable to connect to the original 5V from the monitor]]
[[File:Gotek-internal.jpg|thumb|Internal GOTEK with 3D printed frame and 26/34 pin adapter PCB]]

== About the GOTEK ==

GOTEK is a floppy drive emulator which can be directly attached to computers instead of a normal floppy drive. The drives are popular and cheap additions to many 80s and 90s computers including the Amstrad CPC.

The basic Gotek has a 7-segment 2 digit display which shows the currently selected disk image, a USB socket for a USB memory stick, and 2 buttons to choose previous and next image.

There are additional mods that can be added:
* speaker (to simulate the sound of the read/write head stepping as heard in a real drive)
* eject button
* rotary dial (turn the dial to select the disc image)
* LCD/OLED display (this shows more information including the name of the image)

The most recent version of the GOTEK (SFRKC30.AT4.35, based on the AT32F435 chip) usually already comes with OLED display and rotary encoder but is also more expensive than the basic models.

In addition to the GOTEK you also need
* 5V power (e.g. USB power supplies will work - or you can use the monitor's 5V power output with a Y-splitter cable)
* a 34pin ribbon cable to connect it to the CPC (e.g. an old PC floppy cable which has both 3.5" and 5.25" connectors)
* connector cable to update firmware of the GOTEK (depends on firmware type)

CPC Disk images are put onto a USB drive which is plugged into the front of the Gotek. On the GOTEK a disk image is selected (via buttons or rotary encoder) and then the GOTEK behaves almost exactly as if it is a normal drive connected to the CPC with the disk being inserted.

There is only a small difference compared to a real drive with older models: the disc motor signal is not connected internally to the Gotek. This means the ready signal will be active even if the disc motor is off. The new model SFRKC30.AT4.35 can pass the motor signal and reacts (delayed if wanted) to it for the ready signal. See below for FlashFloppy firmware.

The GOTEK can replace the internal drive of the 664/6128, e.g. if the internal drive is broken. Or it can be used as the external drive B. It can even work as a 3.5" or 5.25" drive for example with Parados or VDOS.

== Firmware Update ==

Before the GOTEK can be used with the Amstrad CPC it needs to be flashed with a custom firmware.

The process depends on the type and firmware and is documented on the homepages of the respective firmwares (see below).

===HxC Floppy Emulator firmware===

There is a version of the [https://hxc2001.com HxC Floppy Emulator] firmware that can be used on the Gotek. It must be purchased from the HxC website and can then be installed and used.

The firmware supports multiple computers and their disk image formats as well as the HFE v1 & v3 file formats.

Once the firmware has been installed into a Gotek it can be updated through the USB memory stick.

===FlashFloppy firmware===

[https://github.com/keirf/FlashFloppy FlashFloppy] is probably the most popular firmware for the GOTEK. It's well supported by the author Keir Fraser and [https://github.com/keirf/flashfloppy/blob/master/COPYING completely free].

The firmware supports multiple computers and their disk image formats.

Firmware installation is more easy than HxC firmware and only needs a USB-A to USB-A cable and the use of the original software of the microcontroller vendor to install the firmware. The process is very well documented on the FlashFloppy wiki.

Once installed further updates can be performed via the USB memory stick.

On the CPC, the following FF.cfg setting can be recommended:

<pre>
# Floppy-drive interface mode
interface = shugart

# Host platform
host = unspecified

# Pins 2 & 34 output (drive->host) manual configuration
pin02 = high
pin34 = rdy

# Rotational offset of disk after a track change
track-change = realtime

# Rotational offset of disk after draining a write to Flash
write-drain = realtime

# Index pulses suppressed when RDATA and WDATA inactive?
index-suppression = yes

# Milliseconds from head-step start to RDATA active.
head-settle-ms = 12

# Milliseconds delay from motor-on to drive ready.
motor-delay = 200
</pre>

The rest of the settings can be used to your liking as they depend on preference and not on hardware emulation.

== Models ==

The best Gotek to buy currently (12/22) is the Model SFRKC30.AT4.35.

This model features a Artery AT32F435 APU and as well a motor jumper. This completes the emulation as it simulates the motor spin-up time. They are usually offered with Rotary encoder and with OLED display.

On the CPC also the AT32F415 models can be a good alternative. They are cheaper and can be upgraded with rotary encoder and OLED display.

For full details on which models to use and which to avoid, see here:
[https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]

==Physical connection==

===CPC 464 / DDI===

You can directly connect the GOTEK to the DDI-1 cable connector however you would need to cut off the noses on the bottom of the cable - or you use a short IDC extension cable to avoid cutting of the noses. Please keep in mind that the DDI-1 is powered by the original FD-1 3" drive so you still need the FD-1 or need to power the DDI-1 via an alternative method.

===CPC 664 / 6128 external===

A 34 pin IDC floppy cable as used in old PCs is perfect. If it even has a 5.25" edge connector you can use it directly.

For German Schneider/Amstrad 6128 models you will need a Centronics connector instead of the edge connector.

The 6128 Plus also needs a Centronics connector but with a slightly different pinout.

[[Image:Floppy_Cable.png|600px|centre]]

For full details look here: [[DIY:Floppy_Drives#Multi-Adaptor_Cable_for_External_Floppies_.2F_HxC_emulator]]

===Replacing the drive in a CPC 664 / 6128 or FD-1===

As connections are slightly different from a 3.5" drive the connections to the GOTEK need to be modified to replace a 3" disk drive in the original 664/6128 or FD-1 case. Also, as the size of a GOTEK is different from a 3" drive a (usually 3D printed) frame is required to hold the GOTEK in place.

* adapt the 26 pin floppy cable of the CPC to fit to the 34 pin connector on the GOTEK - [[DIY:Floppy_Drives#Adaptor_Cable_for_Internal_Floppies_.2F_HxC_emulator|26 to 34 pin adapter]]
* switch 5V and 12V on the power connector as otherwise you would fry your GOTEK with 12V
* set the jumper on the GOTEK from S1 to S0.
* put the GOTEK into a (3D printed) frame to properly fit into the 3" drive slot

''Note: If you remove the 3" drive from the CPC it no longer needs the 12V power supply. This means you can now use a single 5V power supply to run your CPC, including the MP-1 or CTM640 for the 464.''

====adapters====

There are prebuilt adapters that can be plugged into the rear of the GOTEK and provide connectors for the 3" connector cables. These can usually be bought on Ebay.

Alternatively DIY adapters can be done easily. '''Make 100% sure that you don't accidentally connect the 12V to the GOTEK as this will definitely fry your GOTEK.'''

[[Image:Internal_HxC_Cable.png|600px|centre]]

====Gotek mod====

If you don't plan to use the GOTEK on any other machine than the CPC you can also make a few modifications to the GOTEK directly and can use the original cables without modifications or adapters.

# cut the pin that is labelled as 5V on the GOTEK. Either the whole pin on the side of the drive, so only 3 pins remain or a little more subtle on the backside of the connector so there's a gap between the pin and the PCB. This ensures 12V is no longer fed into the GOTEK.
# make a connection from pin 1 to pin 4 of the power connector on the backside of the PCB to connect the GOTEK to the 5V coming from the CPC.
# optionally: remove the first 4 pairs of the 34pin connector. Either just cut the pins or desolder them if you have the equipment. This step is not mandatory as you can just connect the cable to the outer most part of the connector.
# make a small bridge on the backside of the GOTEK PCB between pin 8 and 10.
# optionally: cut the trace on the PCB next to pin 10. Alternatively remember to NEVER close S0 on the GOTEK (or cut the S0 pins).
# set the jumper on the GOTEK to S1

Now you can connect the original cables directly to the GOTEK as if it was built for the CPC.

<gallery>
gotekmod1.jpg|pins to cut
gotekmod2.jpg|new connections
gotekmod3.jpg|cables attached
</gallery>

==HXC Manager==

Despite its name this software works with both FlashFloppy and HxC firmware.

Especially when using the 3 digit display the [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager] offers a great alternative to organise and mount DSK images. You can select 20 images and assign them to 20 slots which you navigate via the up/down buttons on the GOTEK.

[[File:Hxcmanager.jpg|thumbnail|none]]

==Related==
* [[HxC_Floppy_Emulator|HxC Floppy Emulator]]
* [[FlashFloppy]]
* [[ABBA_switch|ABBA switch - switch drive A to B and B to A]]
* [[Guide_on_how_to_connect_a_3.5#Primary_drive_setting_.28OPTIONAL.29|Forcing drive B to be Drive A]]

==Links==
* [https://github.com/keirf/FlashFloppy FlashFloppy on github]
* [https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]
* [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager]
* [https://hxc2001.com/ HxC Floppy Emulator Homepage]
* [http://www.cpcwiki.eu/forum/applications/cubeios-fat16fat32-rom-for-the-cpc's-with-xmass/ OS-Support]
* [https://youtu.be/QSLcgWLRztE Un Gotek sur CPC 664/6128 sans rien démonter] by [[Rodrik Studio]]
* [https://youtu.be/E3raN1yi54c L'ultime Gotek que j'ai dessiné pour CPC] by [[Rodrik Studio]]

[[Category:Peripherals]] [[Category:DIY]][[Category:DATA Storage]] [[Category:Emulator]]

File:Gotekmod3.jpg

2025-10-23T22:45:48Z

Eto:

File:Gotekmod2.jpg

2025-10-23T22:45:31Z

Eto:

File:Gotekmod1.jpg

2025-10-23T22:45:13Z

Eto:

Gotek

2025-10-23T07:34:52Z

Eto: /* Gotek mod */

[[File:Gotek standard.jpg|thumb|right|Standard Gotek drive]]
[[File:Custom Gotek drive.jpg|thumb|right|Custom Gotek drive by [[Rodrik Studio]]]]
[[File:Gotek external.jpg|thumb|External GOTEK for a Schneider CPC 6128 with Centronics cable, 3D printed top cover and splitter cable to connect to the original 5V from the monitor]]
[[File:Gotek-internal.jpg|thumb|Internal GOTEK with 3D printed frame and 26/34 pin adapter PCB]]

== About the GOTEK ==

GOTEK is a floppy drive emulator which can be directly attached to computers instead of a normal floppy drive. The drives are popular and cheap additions to many 80s and 90s computers including the Amstrad CPC.

The basic Gotek has a 7-segment 2 digit display which shows the currently selected disk image, a USB socket for a USB memory stick, and 2 buttons to choose previous and next image.

There are additional mods that can be added:
* speaker (to simulate the sound of the read/write head stepping as heard in a real drive)
* eject button
* rotary dial (turn the dial to select the disc image)
* LCD/OLED display (this shows more information including the name of the image)

The most recent version of the GOTEK (SFRKC30.AT4.35, based on the AT32F435 chip) usually already comes with OLED display and rotary encoder but is also more expensive than the basic models.

In addition to the GOTEK you also need
* 5V power (e.g. USB power supplies will work - or you can use the monitor's 5V power output with a Y-splitter cable)
* a 34pin ribbon cable to connect it to the CPC (e.g. an old PC floppy cable which has both 3.5" and 5.25" connectors)
* connector cable to update firmware of the GOTEK (depends on firmware type)

CPC Disk images are put onto a USB drive which is plugged into the front of the Gotek. On the GOTEK a disk image is selected (via buttons or rotary encoder) and then the GOTEK behaves almost exactly as if it is a normal drive connected to the CPC with the disk being inserted.

There is only a small difference compared to a real drive with older models: the disc motor signal is not connected internally to the Gotek. This means the ready signal will be active even if the disc motor is off. The new model SFRKC30.AT4.35 can pass the motor signal and reacts (delayed if wanted) to it for the ready signal. See below for FlashFloppy firmware.

The GOTEK can replace the internal drive of the 664/6128, e.g. if the internal drive is broken. Or it can be used as the external drive B. It can even work as a 3.5" or 5.25" drive for example with Parados or VDOS.

== Firmware Update ==

Before the GOTEK can be used with the Amstrad CPC it needs to be flashed with a custom firmware.

The process depends on the type and firmware and is documented on the homepages of the respective firmwares (see below).

===HxC Floppy Emulator firmware===

There is a version of the [https://hxc2001.com HxC Floppy Emulator] firmware that can be used on the Gotek. It must be purchased from the HxC website and can then be installed and used.

The firmware supports multiple computers and their disk image formats as well as the HFE v1 & v3 file formats.

Once the firmware has been installed into a Gotek it can be updated through the USB memory stick.

===FlashFloppy firmware===

[https://github.com/keirf/FlashFloppy FlashFloppy] is probably the most popular firmware for the GOTEK. It's well supported by the author Keir Fraser and [https://github.com/keirf/flashfloppy/blob/master/COPYING completely free].

The firmware supports multiple computers and their disk image formats.

Firmware installation is more easy than HxC firmware and only needs a USB-A to USB-A cable and the use of the original software of the microcontroller vendor to install the firmware. The process is very well documented on the FlashFloppy wiki.

Once installed further updates can be performed via the USB memory stick.

On the CPC, the following FF.cfg setting can be recommended:

<pre>
# Floppy-drive interface mode
interface = shugart

# Host platform
host = unspecified

# Pins 2 & 34 output (drive->host) manual configuration
pin02 = high
pin34 = rdy

# Rotational offset of disk after a track change
track-change = realtime

# Rotational offset of disk after draining a write to Flash
write-drain = realtime

# Index pulses suppressed when RDATA and WDATA inactive?
index-suppression = yes

# Milliseconds from head-step start to RDATA active.
head-settle-ms = 12

# Milliseconds delay from motor-on to drive ready.
motor-delay = 200
</pre>

The rest of the settings can be used to your liking as they depend on preference and not on hardware emulation.

== Models ==

The best Gotek to buy currently (12/22) is the Model SFRKC30.AT4.35.

This model features a Artery AT32F435 APU and as well a motor jumper. This completes the emulation as it simulates the motor spin-up time. They are usually offered with Rotary encoder and with OLED display.

On the CPC also the AT32F415 models can be a good alternative. They are cheaper and can be upgraded with rotary encoder and OLED display.

For full details on which models to use and which to avoid, see here:
[https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]

==Physical connection==

===CPC 464 / DDI===

You can directly connect the GOTEK to the DDI-1 cable connector however you would need to cut off the noses on the bottom of the cable - or you use a short IDC extension cable to avoid cutting of the noses. Please keep in mind that the DDI-1 is powered by the original FD-1 3" drive so you still need the FD-1 or need to power the DDI-1 via an alternative method.

===CPC 664 / 6128 external===

A 34 pin IDC floppy cable as used in old PCs is perfect. If it even has a 5.25" edge connector you can use it directly.

For German Schneider/Amstrad 6128 models you will need a Centronics connector instead of the edge connector.

The 6128 Plus also needs a Centronics connector but with a slightly different pinout.

[[Image:Floppy_Cable.png|600px|centre]]

For full details look here: [[DIY:Floppy_Drives#Multi-Adaptor_Cable_for_External_Floppies_.2F_HxC_emulator]]

===Replacing the drive in a CPC 664 / 6128 or FD-1===

As connections are slightly different from a 3.5" drive the connections to the GOTEK need to be modified to replace a 3" disk drive in the original 664/6128 or FD-1 case. Also, as the size of a GOTEK is different from a 3" drive a (usually 3D printed) frame is required to hold the GOTEK in place.

* adapt the 26 pin floppy cable of the CPC to fit to the 34 pin connector on the GOTEK - [[DIY:Floppy_Drives#Adaptor_Cable_for_Internal_Floppies_.2F_HxC_emulator|26 to 34 pin adapter]]
* switch 5V and 12V on the power connector as otherwise you would fry your GOTEK with 12V
* set the jumper on the GOTEK from S1 to S0.
* put the GOTEK into a (3D printed) frame to properly fit into the 3" drive slot

''Note: If you remove the 3" drive from the CPC it no longer needs the 12V power supply. This means you can now use a single 5V power supply to run your CPC, including the MP-1 or CTM640 for the 464.''

====adapters====

There are prebuilt adapters that can be plugged into the rear of the GOTEK and provide connectors for the 3" connector cables. These can usually be bought on Ebay.

Alternatively DIY adapters can be done easily. '''Make 100% sure that you don't accidentally connect the 12V to the GOTEK as this will definitely fry your GOTEK.'''

[[Image:Internal_HxC_Cable.png|600px|centre]]

====Gotek mod====

If you don't plan to use the GOTEK on any other machine than the CPC you can also make a few modifications to the GOTEK directly and can use the original cables without modifications or adapters.

# cut the pin that is labelled as 5V on the GOTEK. Either the whole pin on the side of the drive, so only 3 pins remain or a little more subtle on the backside of the connector so there's a gap between the pin and the PCB. This ensures 12V is no longer fed into the GOTEK.
# make a connection from pin 1 to pin 4 of the power connector on the backside of the PCB to connect the GOTEK to the 5V coming from the CPC.
# optionally: remove the first 4 pairs of the 34pin connector. Either just cut the pins or desolder them if you have the equipment. This step is not mandatory as you can just connect the cable to the outer most part of the connector.
# make a small bridge on the backside of the GOTEK PCB between pin 8 and 10.
# optionally: cut the trace on the PCB next to pin 10. Alternatively remember to NEVER close S0 on the GOTEK (or cut the S0 pins).
# set the jumper on the GOTEK to S1

Now you can connect the original cables directly to the GOTEK as if it was built for the CPC.

==HXC Manager==

Despite its name this software works with both FlashFloppy and HxC firmware.

Especially when using the 3 digit display the [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager] offers a great alternative to organise and mount DSK images. You can select 20 images and assign them to 20 slots which you navigate via the up/down buttons on the GOTEK.

[[File:Hxcmanager.jpg|thumbnail|none]]

==Related==
* [[HxC_Floppy_Emulator|HxC Floppy Emulator]]
* [[FlashFloppy]]
* [[ABBA_switch|ABBA switch - switch drive A to B and B to A]]
* [[Guide_on_how_to_connect_a_3.5#Primary_drive_setting_.28OPTIONAL.29|Forcing drive B to be Drive A]]

==Links==
* [https://github.com/keirf/FlashFloppy FlashFloppy on github]
* [https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]
* [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager]
* [https://hxc2001.com/ HxC Floppy Emulator Homepage]
* [http://www.cpcwiki.eu/forum/applications/cubeios-fat16fat32-rom-for-the-cpc's-with-xmass/ OS-Support]
* [https://youtu.be/QSLcgWLRztE Un Gotek sur CPC 664/6128 sans rien démonter] by [[Rodrik Studio]]
* [https://youtu.be/E3raN1yi54c L'ultime Gotek que j'ai dessiné pour CPC] by [[Rodrik Studio]]

[[Category:Peripherals]] [[Category:DIY]][[Category:DATA Storage]] [[Category:Emulator]]

Gotek

2025-10-23T07:34:20Z

Eto: /* CPC 664 / 6128 internal */

[[File:Gotek standard.jpg|thumb|right|Standard Gotek drive]]
[[File:Custom Gotek drive.jpg|thumb|right|Custom Gotek drive by [[Rodrik Studio]]]]
[[File:Gotek external.jpg|thumb|External GOTEK for a Schneider CPC 6128 with Centronics cable, 3D printed top cover and splitter cable to connect to the original 5V from the monitor]]
[[File:Gotek-internal.jpg|thumb|Internal GOTEK with 3D printed frame and 26/34 pin adapter PCB]]

== About the GOTEK ==

GOTEK is a floppy drive emulator which can be directly attached to computers instead of a normal floppy drive. The drives are popular and cheap additions to many 80s and 90s computers including the Amstrad CPC.

The basic Gotek has a 7-segment 2 digit display which shows the currently selected disk image, a USB socket for a USB memory stick, and 2 buttons to choose previous and next image.

There are additional mods that can be added:
* speaker (to simulate the sound of the read/write head stepping as heard in a real drive)
* eject button
* rotary dial (turn the dial to select the disc image)
* LCD/OLED display (this shows more information including the name of the image)

The most recent version of the GOTEK (SFRKC30.AT4.35, based on the AT32F435 chip) usually already comes with OLED display and rotary encoder but is also more expensive than the basic models.

In addition to the GOTEK you also need
* 5V power (e.g. USB power supplies will work - or you can use the monitor's 5V power output with a Y-splitter cable)
* a 34pin ribbon cable to connect it to the CPC (e.g. an old PC floppy cable which has both 3.5" and 5.25" connectors)
* connector cable to update firmware of the GOTEK (depends on firmware type)

CPC Disk images are put onto a USB drive which is plugged into the front of the Gotek. On the GOTEK a disk image is selected (via buttons or rotary encoder) and then the GOTEK behaves almost exactly as if it is a normal drive connected to the CPC with the disk being inserted.

There is only a small difference compared to a real drive with older models: the disc motor signal is not connected internally to the Gotek. This means the ready signal will be active even if the disc motor is off. The new model SFRKC30.AT4.35 can pass the motor signal and reacts (delayed if wanted) to it for the ready signal. See below for FlashFloppy firmware.

The GOTEK can replace the internal drive of the 664/6128, e.g. if the internal drive is broken. Or it can be used as the external drive B. It can even work as a 3.5" or 5.25" drive for example with Parados or VDOS.

== Firmware Update ==

Before the GOTEK can be used with the Amstrad CPC it needs to be flashed with a custom firmware.

The process depends on the type and firmware and is documented on the homepages of the respective firmwares (see below).

===HxC Floppy Emulator firmware===

There is a version of the [https://hxc2001.com HxC Floppy Emulator] firmware that can be used on the Gotek. It must be purchased from the HxC website and can then be installed and used.

The firmware supports multiple computers and their disk image formats as well as the HFE v1 & v3 file formats.

Once the firmware has been installed into a Gotek it can be updated through the USB memory stick.

===FlashFloppy firmware===

[https://github.com/keirf/FlashFloppy FlashFloppy] is probably the most popular firmware for the GOTEK. It's well supported by the author Keir Fraser and [https://github.com/keirf/flashfloppy/blob/master/COPYING completely free].

The firmware supports multiple computers and their disk image formats.

Firmware installation is more easy than HxC firmware and only needs a USB-A to USB-A cable and the use of the original software of the microcontroller vendor to install the firmware. The process is very well documented on the FlashFloppy wiki.

Once installed further updates can be performed via the USB memory stick.

On the CPC, the following FF.cfg setting can be recommended:

<pre>
# Floppy-drive interface mode
interface = shugart

# Host platform
host = unspecified

# Pins 2 & 34 output (drive->host) manual configuration
pin02 = high
pin34 = rdy

# Rotational offset of disk after a track change
track-change = realtime

# Rotational offset of disk after draining a write to Flash
write-drain = realtime

# Index pulses suppressed when RDATA and WDATA inactive?
index-suppression = yes

# Milliseconds from head-step start to RDATA active.
head-settle-ms = 12

# Milliseconds delay from motor-on to drive ready.
motor-delay = 200
</pre>

The rest of the settings can be used to your liking as they depend on preference and not on hardware emulation.

== Models ==

The best Gotek to buy currently (12/22) is the Model SFRKC30.AT4.35.

This model features a Artery AT32F435 APU and as well a motor jumper. This completes the emulation as it simulates the motor spin-up time. They are usually offered with Rotary encoder and with OLED display.

On the CPC also the AT32F415 models can be a good alternative. They are cheaper and can be upgraded with rotary encoder and OLED display.

For full details on which models to use and which to avoid, see here:
[https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]

==Physical connection==

===CPC 464 / DDI===

You can directly connect the GOTEK to the DDI-1 cable connector however you would need to cut off the noses on the bottom of the cable - or you use a short IDC extension cable to avoid cutting of the noses. Please keep in mind that the DDI-1 is powered by the original FD-1 3" drive so you still need the FD-1 or need to power the DDI-1 via an alternative method.

===CPC 664 / 6128 external===

A 34 pin IDC floppy cable as used in old PCs is perfect. If it even has a 5.25" edge connector you can use it directly.

For German Schneider/Amstrad 6128 models you will need a Centronics connector instead of the edge connector.

The 6128 Plus also needs a Centronics connector but with a slightly different pinout.

[[Image:Floppy_Cable.png|600px|centre]]

For full details look here: [[DIY:Floppy_Drives#Multi-Adaptor_Cable_for_External_Floppies_.2F_HxC_emulator]]

===Replacing the drive in a CPC 664 / 6128 or FD-1===

As connections are slightly different from a 3.5" drive the connections to the GOTEK need to be modified to replace a 3" disk drive in the original 664/6128 or FD-1 case. Also, as the size of a GOTEK is different from a 3" drive a (usually 3D printed) frame is required to hold the GOTEK in place.

* adapt the 26 pin floppy cable of the CPC to fit to the 34 pin connector on the GOTEK - [[DIY:Floppy_Drives#Adaptor_Cable_for_Internal_Floppies_.2F_HxC_emulator|26 to 34 pin adapter]]
* switch 5V and 12V on the power connector as otherwise you would fry your GOTEK with 12V
* set the jumper on the GOTEK from S1 to S0.
* put the GOTEK into a (3D printed) frame to properly fit into the 3" drive slot

''Note: If you remove the 3" drive from the CPC it no longer needs the 12V power supply. This means you can now use a single 5V power supply to run your CPC, including the MP-1 or CTM640 for the 464.''

====adapters====

There are prebuilt adapters that can be plugged into the rear of the GOTEK and provide connectors for the 3" connector cables. These can usually be bought on Ebay.

Alternatively DIY adapters can be done easily. '''Make 100% sure that you don't accidentally connect the 12V to the GOTEK as this will definitely fry your GOTEK.'''

[[Image:Internal_HxC_Cable.png|600px|centre]]

====Gotek mod====

If you don't plan to use the GOTEK on any other machine than the CPC you can also make a few modifications to the GOTEK directly and can use the original cables without modifications or adapters.

1) cut the pin that is labelled as 5V on the GOTEK. Either the whole pin on the side of the drive, so only 3 pins remain or a little more subtle on the backside of the connector so there's a gap between the pin and the PCB. This ensures 12V is no longer fed into the GOTEK.
2) make a connection from pin 1 to pin 4 of the power connector on the backside of the PCB to connect the GOTEK to the 5V coming from the CPC.
3) optionally: remove the first 4 pairs of the 34pin connector. Either just cut the pins or desolder them if you have the equipment. This step is not mandatory as you can just connect the cable to the outer most part of the connector.
4) make a small bridge on the backside of the GOTEK PCB between pin 8 and 10.
5) optionally: cut the trace on the PCB next to pin 10. Alternatively remember to NEVER close S0 on the GOTEK (or cut the S0 pins).
5) set the jumper on the GOTEK to S1

Now you can connect the original cables directly to the GOTEK as if it was built for the CPC.

==HXC Manager==

Despite its name this software works with both FlashFloppy and HxC firmware.

Especially when using the 3 digit display the [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager] offers a great alternative to organise and mount DSK images. You can select 20 images and assign them to 20 slots which you navigate via the up/down buttons on the GOTEK.

[[File:Hxcmanager.jpg|thumbnail|none]]

==Related==
* [[HxC_Floppy_Emulator|HxC Floppy Emulator]]
* [[FlashFloppy]]
* [[ABBA_switch|ABBA switch - switch drive A to B and B to A]]
* [[Guide_on_how_to_connect_a_3.5#Primary_drive_setting_.28OPTIONAL.29|Forcing drive B to be Drive A]]

==Links==
* [https://github.com/keirf/FlashFloppy FlashFloppy on github]
* [https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]
* [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager]
* [https://hxc2001.com/ HxC Floppy Emulator Homepage]
* [http://www.cpcwiki.eu/forum/applications/cubeios-fat16fat32-rom-for-the-cpc's-with-xmass/ OS-Support]
* [https://youtu.be/QSLcgWLRztE Un Gotek sur CPC 664/6128 sans rien démonter] by [[Rodrik Studio]]
* [https://youtu.be/E3raN1yi54c L'ultime Gotek que j'ai dessiné pour CPC] by [[Rodrik Studio]]

[[Category:Peripherals]] [[Category:DIY]][[Category:DATA Storage]] [[Category:Emulator]]

CPC iRAM

2025-10-20T09:31:49Z

Eto:

[[File:Iram640.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

So far no incompatibilities have been reported.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

Unlike other RAM expansions the iRAM can be used in parallel to an external RAM expansion. The iRAM has priority over external RAM expansions and only requests above the iRAM memory limit will be passed to an external RAM expansion. External memory expansions that are smaller than the iRAM will be ignored. This is particularly helpful for external feature-expansions that also provide a RAM expansion. Those expansions usually cannot be connected in parallel to another (bigger) RAM expansion. E.g. DDI-5/6, ULIFAC and Pico CPC limit the CPC to the RAM provided by those expansions. A great use case is to put the ULIFAC in ROM board mode which replaces the full or parts of the expanded RAM with ROM slots - but with the iRAM installed the CPC still has access to the full RAM provided by the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

== currently in development ==

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, final PCB design will be tested, will be released in late 2025

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

CPC iRAM

2025-10-20T09:18:12Z

Eto:

[[File:Iram640.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

== Compatibility ==

So far no incompatibilities have been reported.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

Unlike other RAM expansions the iRAM can be used in parallel to an external RAM expansion. The iRAM has priority over external RAM expansions and only requests above the iRAM memory limit will be passed to an external RAM expansion. External memory expansions that are smaller than the iRAM will be ignored. This is particularly helpful for external feature-expansions that also provide a RAM expansion. Those expansions usually cannot be connected in parallel to another (bigger) RAM expansion. E.g. DDI-5/6, ULIFAC and Pico CPC limit the CPC to the RAM provided by those expansions. A great use case is to put the ULIFAC in ROM board mode which limits the RAM to 192 or 256K - but with the iRAM installed the CPC still has access to the full RAM provided by the iRAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

== currently in development ==

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, final PCB design will be tested, will be released in late 2025

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

Schematics

2025-10-02T10:22:17Z

Eto: /* CPC Classic Schematics */

== CPC Classic Schematics ==

<gallery caption="System Schematics">
File:464Schematic_new.png|Amstrad CPC464 (new)
File:Schaltplan_cpc_464.jpg|Amstrad CPC464 (scan)
File:CPC664_Schematic.png|Amstrad CPC664 (main)
File:CPC664 Disk Interface Schematic.png|Amstrad CPC664 (disc)
File:CPC6128_Schematic.png|Amstrad CPC6128 (main)
File:CPC6128 Disk Interface Schematic.png|Amstrad CPC6128 (disc)
File:CPC_Disc_Cassette_Schematic.gif|Disc And Cassette Schematics
</gallery>

# Important: There are several versions of the 464 and 6128 motherboards with more or less different schematics. Make sure to check the service manuals for your specific motherboard version if you recognize a difference.
# HighRes scalable version of the CPC464 Schematics: [[Media:464SchematicRedraw_white.pdf|464SchematicRedraw_white.pdf]]
# A full KiCad 6 schematic and pcb layout for the MC0020x CPC6128 boards (featuring the "new" gate array and 24-pin data separator IC) is available at https://github.com/pelrun/cpc-schematics

<gallery caption="Monitor Schematics">
File:GT64_Schematic.png|GT64
File:GT65_Schematic.png|GT65
File:CTM640_Schematic.png|CTM640
File:CTM644_Schematic.png|CTM644
</gallery>

<gallery caption="Disk Drive Interface Schematics">
File:DDI_Schematic.png|DDI
</gallery>

== CPC Plus Schematics ==

<gallery caption="Original Scans (high-resolution, with lots of blank space)">
File:CPC_Plus_CPU_Schematic.jpg|CPU Schematic
File:CPC_Plus_Asic_Schematic.GIF|Asic Schematic
File:CPC_Plus_Vid_Mem_Schematic.jpg|Video and Memory Schematic
File:CPC_Plus_Cassette_Schematic.jpg|Cassette Schematic
</gallery>

<gallery caption="Edited (lower resolution, less blank space, more concentrated info)">
File:Edited CPC_Plus_CPU_Schematic.gif|CPU Schematic
File:Edited CPC_Plus_Asic_Schematic.gif|Asic Schematic
File:Edited CPC_Plus_Vid_Mem_Schematic.gif|Video and Memory Schematic
File:Edited CPC_Plus_Cassette_Schematic.gif|Cassette Schematic
</gallery>

<gallery caption="Monitor Schematics">
File:MM12_Schematic.gif|MM12 Schematic
File:CM14_Power_Sound_Schematic.gif|CM14 Power And Sound Schematic
File:CM14_Video_Schematic.gif|CM14 Video Schematic
</gallery>

== GX4000 Schematics ==

<gallery caption="System Schematics">
File:GX4000_CPU_Schematic.png|CPU Schematic
File:GX4000_ASIC_Schematic.png|Asic Schematic
File:GX4000_Memory_Video_Schematic.png|Video and Memory Schematic
File:GX4000_RGB_Schematic.png|RGB Conversion Schematic
File:GX4000_Power_Schematic.png|Power Supply Schematic
</gallery>

<gallery caption="GX4000 - Edited version (lower resolution, less white space)">
File:Edited GX4000 ASIC Schematic.gif|ASIC Schematic
File:Edited GX4000 Vid Mem Cpu Schematic.gif|CPU Video Memory
File:Edited GX4000 RGB Power Schematic.gif|RGB and Power (PAL)
File:Edited GX4000 French Schematic.gif|RGB and Power (French)

</gallery>

== KC Compact Schematics (East German CPC clone) ==

<gallery>
File:Kcc schematic cpu io.gif|CPU and I/O Schematic
File:Kcc schematic memory.gif|Memory Schematic
File:Kcc schematic modulator.gif|Modulator Schematic
File:Kcc schematic video power.gif|Video and Power Schematic
File:Kcc block diagram.gif|Block Diagram
File:Kcc component map mainboard.gif|Component Map (Mainboard)
File:Kcc component map modulator.gif|Component Map (Modulator)
</gallery>

== Aleste 520EX Schematics (Russian CPC clone) ==

<gallery>
File:Aleste-Schematic1.gif|Schematic 1/4
File:Aleste-Schematic2.gif|Schematic 2/4
File:Aleste-Schematic3.gif|Schematic 3/4
File:Aleste-Schematic4.gif|Schematic 4/4
File:Aleste-Component-Map.gif|Component Map
</gallery>

For reference, the original '''unedited''' schematics are here:
[[Media:Black-Aleste-Schematic1.gif|Sheet 1]],
[[Media:Black-Aleste-Schematic2.gif|Sheet 2]],
[[Media:Black-Aleste-Schematic3.gif|Sheet 3]],
[[Media:Black-Aleste-Schematic4.gif|Sheet 4]], and
[[Media:Black-Aleste-Component-Map.gif|Component Map]]

== Additional Hardware ==
* [[3 1/2" & 5 1/4" Disk Drives]] (errr. no schematics here, no pinouts, nothing?)
* [[Peripherals]] (contains schematics - as far as any do exist)
* [[Joystick Y-cables]] (with schematics)
* [[TV Scart cable]] (with schematics)

* '''Note''' - Further schematics are found in the [[Service Manuals]].

== Datasheets ==
* [[media:BCD to Decimal Decoders HD74LS145.pdf|Decoder 74LS145 datasheet]]
* [[media:Line to 1-Line Data Selectors-Multiplexers x2 HD74LS153.pdf|MUX 74LS153 datasheet]]
* [[media:Buffers Lines Drivers-Receivers x8 HD74LS244.pdf|Data buffer 74LS244 datasheet]]
* [[media:Gates Flip-Flops x8 HD74LS273.pdf|Printer port latch 74LS273 datasheet]]
* [[media:D-type Transparent Latches x8 HD74LS373.pdf|Data latch/buffer 74LS373 datasheet]]
* [[media:MC74HC4051 datasheet.pdf|8-Analog multiplexer 74HC4051 datasheet]]

[[Category:Hardware| ]][[Category:CPC Internal Components| ]][[Category:Amstrad CPC media]][[Category:Picture Gallery]][[Category:Electronic Component| ]][[Category:Clones|*]][[Category:CPC Plus|*]]

PSG

2025-09-28T14:08:15Z

Eto: /* BASIC Sound Test */

The Programmable Sound Generator (PSG) is a sound chip designed by General Instrument (GI) in 1978. The specific model used in the CPC is the AY-3-8912 chip.

The PSG is quite primitive. It is able to output a square wave and/or white noise in three separate sound channels (named Channel A, B and C).

Some other 8-bit systems used more sophisticated soundchips such as the [https://youtu.be/7pONRbIHT_w C64 SID], the [https://youtu.be/BANwL2sQ0DM NES APU] and the [https://youtu.be/-mdjiWBYIqU Gameboy soundchip].

== I/O Access ==

The PSG has 16 read/writeable data registers, and a write-only index register.

While there are only 16 data registers, the index register is 8-bit, not 4-bit. The higher 4-bits of the index register are used as chip select.

Both the index and data registers are accessed through [[8255|PPI Port A]], depending on the current setting of the BC1 and BDIR bits in [[8255|PPI Port C]]. The four possible combinations are:

{| class="wikitable"
|-
!PPI Port C
!BDIR
!BC1
!Function
|-
|00xxxxxx||0||0||Inactive
|-
|01xxxxxx||0||1||Read from selected PSG register
|-
|10xxxxxx||1||0||Write to selected PSG register
|-
|11xxxxxx||1||1||Select PSG register
|}

The procedure to write data to a specific PSG register from the PPI is quite tedious. It consists of the following steps:
# Write the register number to PPI Port A
# set BC1/BDIR to Select Register
# and back to Inactive
# Now write the data to PPI Port A
# set BC1/BDIR to Write Data
# and back to Inactive.

You must use 3 OUTs to send a value to an AY register, even if you don't change registers in the meantime. [https://www.cpcwiki.eu/forum/programming/interesting-walkthrough-video-coding-a-pet-to-play-samples-at-60khz/msg250874/#msg250874 Source]

So you have to enter the data on F4. Then on F6, select the type of data (bdir/bc1>>#10) and validate everything (bdir/bc1>>00). Otherwise, the data in other AY registers becomes corrupted quite quickly.

Consult this article for more information: [[How to access the PSG via PPI]]

 

== PSG Registers ==

===00h - Channel A Tone Frequency Low (8bit)===
===01h - Channel A Tone Frequency High (4bit)===
===02h - Channel B Tone Frequency Low (8bit)===
===03h - Channel B Tone Frequency High (4bit)===
===04h - Channel C Tone Frequency Low (8bit)===
===05h - Channel C Tone Frequency High (4bit)===
The tone (square wave) frequency in Hertz is calculated as follows:
F = 1MHz / 16 / nn ;with nn in range 1..4095 (nn=0 acts as nn=1)
Possible frequencies are in range from 62500Hz (nn=1) down to approx. 15.26Hz (nn=4095).

===06h - Noise Frequency (5bit)===
The noise frequency in Hertz is calculated as follows:

F = 1MHz / 16 / nn ;with nn in range 1..31 (nn=0 acts as nn=1)

Noise can be output on all 3 channels, but there is only one noise generator (so all channels share the same noise frequency). The noise generator consists of 17bit shift register, and a 1bit noise level (0=LOW or 1=HIGH). These are updated at the selected frequency as follows:

noise_level = noise_level XOR shiftreg.bit0
newbit = shiftreg.bit0 XOR shiftreg.bit3
shiftreg = (shiftreg SHR 1) + (newbit SHL 16)

Note that level isn't set equal to bit0, instead, it toggles when bit0=1.

===07h - Mixer Control Register===
The control register enables or disables the sound channels. Each channel can output a Tone and/or Noise.

Bit 0 Channel A Tone (1=off, 0=on)
Bit 1 Channel B Tone (1=off, 0=on)
Bit 2 Channel C Tone (1=off, 0=on)
Bit 3 Channel A Noise (1=off, 0=on)
Bit 4 Channel B Noise (1=off, 0=on)
Bit 5 Channel C Noise (1=off, 0=on)
Bit 6 Port A Direction (1=output, 0=input) (should be always 0 for CPC)
Bit 7 Port B Direction (1=output, 0=input) (not used in CPC)

If both Tone and Noise are disabled on a channel, then a constant HIGH level is output (useful for digitized speech). If both Tone and Noise are enabled on the same channel, then the signals are ANDed (the signals aren't ADDed) (ie. HIGH is output only if both are HIGH).

===08h - Channel A Volume (0-0Fh=volume, 10h=use envelope instead)===
===09h - Channel B Volume (0-0Fh=volume, 10h=use envelope instead)===
===0Ah - Channel C Volume (0-0Fh=volume, 10h=use envelope instead)===
Defines the volume, 0=off, 15=max. If bit4=1, then the volume is taken from the envelope generator. The volume is non-linear. Below formula does comply with the PSG datasheet, and does more or less match the voltages measured on the CPCs speaker (the voltages on the CPCs stereo connector seem to be slightly different though).
amplitude = max / sqrt(2)^(15-nn)
eg. 15 --> max/1, 14 --> max/1.414, 13 --> max/2, etc.
The volume affects only HIGH levels. LOW levels are always NULL. Ie. sound output toggles between +VOL and NULL (not between +VOL and -VOL).

Digitized samples can be written to the volume registers (mind that volume is non-linear). When doing that, it's best to switch the channel to constant HIGH level (by disabling both Tone and Noise). Another method would be to set tone frequency to 000h or 001h (the resulting frequency is too high to be audible, so the HIGH/LOW levels sound like a constant HALF level).

=== 0Bh - Volume Envelope Frequency Low (8bit) ===
=== 0Ch - Volume Envelope Frequency High (8bit) ===
Envelope step frequency (tone or noise) calculated as follows:

F = 1MHz / 16 / nn ;with nn in range 1..65535 (nn=0 acts as nn=1)

Depending on the envelope shape, the volume is incremented from 0 to 15, or decremented from 15 to 0. In either case it takes 16 steps to complete, the completion time for 16 steps is therefore:

T = nn*256 / 1MHz ;with nn in range 1..65535 (256us .. 16.7 seconds)

=== 0Dh - Volume Envelope Shape (4bit) ===
Writing to this register (re-)starts the envelope. Both components of the envelope's phase are reset. The first step of the envelope has full duration every time. It is never shorted. [https://forums.nesdev.org/viewtopic.php?p=236672#p236672 Source]

The written value specifies the envelope shape, the four bits have the following meaning:

Bit 0 Hold (1=stop envelope past first cycle)
Bit 1 Alternate (1=reverse direction at end of each cycle)
Bit 2 Attack (1=initial direction increase)
Bit 3 Continue (0=same as if Bit0=1 and Bit1=Bit2)

The possible combinations and resulting shapes are:

{| class="wikitable"
|-
! Binary !! Hex !! Shape !! Comment
|-
| 00XX || 00h-03h || <code>\_________</code> || same as 09h
|-
| 01XX || 04h-07h || <code>/_________</code> || same as 0Fh
|-
| 1000 || 08h || <code>\\\\\\\\\\</code> ||
|-
| 1001 || 09h || <code>\_________</code> || volume remains quiet
|-
| 1010 || 0Ah || <code>\/\/\/\/\/</code> ||
|-
| 1011 || 0Bh || <code>\¯¯¯¯¯¯¯¯¯</code> || volume remains high
|-
| 1100 || 0Ch || <code>//////////</code> ||
|-
| 1101 || 0Dh || <code>/¯¯¯¯¯¯¯¯¯</code> || volume remains high
|-
| 1110 || 0Eh || <code>/\/\/\/\/\</code> ||
|-
| 1111 || 0Fh || <code>/_________</code> || volume remains quiet
|}

When using the volume envelope generator, the volume is always increased from 00h to 0Fh (or vice versa), it is not possible to specify a starting/ending point (like from 00h to 07h).

==== Bit 2 (Attack) ====

This bit is only responsible for the starting point of the envelope and the direction. We have:
volume = 0 if attack else 15 # Start at 0 for attack, 15 for decay
direction = 1 if attack else -1 # Upward for attack, downward for decay

==== Bit 3 (Continue), Bit 1 (Alternate) and Bit 0 (Hold) ====

When bit3 = 0, volume and direction at the end of a period are always 0.

When bit3 = 1, bit1 and bit0 determine what happens to volume and direction at the end of a period.

==== Algorithm ====

def envelope_step(volume, direction, shape):
volume += direction
if volume > 15 or volume < 0:
match shape:
case 8 | 12:
volume &= 0x0f # direction is unchanged
case 10 | 14:
direction *= -1
volume += direction
case 11 | 13:
direction = 0
volume = 15
case _:
direction = 0
volume = 0
return volume, direction

=== 0Eh - External Dataregister Port A ===
This register receives data from the CPC keyboard (or joystick), for more information read the chapter about the [[Programming:Keyboard_scanning|CPC Keyboard Matrix]].

This register can be also used as output port by setting bit 6 of the PSG control register to 1 (that would allow to use the six data pins of the joystick connector to output data to external hardware).

=== 0Fh - External Dataregister Port B ===
This register is not used in CPC computers. In detail, a AY-3-8910 sound chip would have external connectors for this register, so that it could be used as a further IO port, but the CPC's sound chip (AY-3-8912, in 28 pin package) doesn't have such connectors, even though the register still does exist internally.

The [[Aleste 520EX]] (russian CPC clone) is a special case: it has a Yamaha YM2149F chip, with SSG Port B being used as 8bit printer port data.

 

== Noise Generator ==

The noise generator uses a [https://en.wikipedia.org/wiki/Linear-feedback_shift_register Linear-Feedback Shift Register] algorithm. The random number generator of the 8910 is a 17-bit shift register.

According to [https://github.com/mamedev/mame/blob/master/src/devices/sound/ay8910.h MAME]: The input to the shift register is bit0 XOR bit3. Bit0 is the output. This was verified on AY-3-8910 and YM2149 chips.

However, the algorithm is described in detail in the [[Media:Microchip ay8930.pdf|AY-8930 datasheet]]. And it disagrees with MAME, the input to the shift register is bit0 XOR bit2. And it seems bit1 is the output.

[[File:AY38910A noise block diagram.png]]

 

== D/A converter table ==
These are the 16-bit values used in Arkos Tracker. They are more accurate than the datasheet you can find, as they were tested electronically by Grim and Zik directly from a real CPC: 0, 231, 695, 1158, 2084, 2779, 4168, 6716, 8105, 13200, 18294, 24315, 32189, 40757, 52799, 65535

For the record, these are [https://groups.google.com/g/comp.sys.sinclair/c/-zCR2kxMryY Matthew (Gasman) Westcott measurements] (normalised) on its ZX Spectrum: 0, 0.0105, 0.0154, 0.0216, 0.0314, 0.0461, 0.0635, 0.1061, 0.1319, 0.2163, 0.2973, 0.3908, 0.5129, 0.6371, 0.8186, 1

The datasheet show different values: 2 steps down = half values down. Thus, the theoretical formula is f(x) = 2 ^ ((x - 15) / 2) with x between 1 and 15.

This is the volume table used by BSC:
[[File:PSG DAC volume table.jpg]]

ETO once started testing the output levels (to be fair, with a multimeter only) and it was very close to the theoretical value based on the data sheet and how the CPC mixes the channels. See [https://www.cpcwiki.eu/forum/technical-support/amstrad-cpc-volume-decibel-table/ Discussion on the forum]

Volume 0 is indeed silent. It is not just logarithmic attenuation where maximum attenuation of a channel is just very quiet and not silent. [https://forums.nesdev.org/viewtopic.php?p=236734#p236734 Source]

 

== Mono and Stereo Output ==
When using the CPC's external stereo jack, the stereo output causes channel A of the PSG to be heard on the left, channel C to be heard on the right and channel B to be heard in the middle. [http://winape.net/help/sound.html Source]

In that case, channel B is output through a bigger resistor to prevent that this channel appears louder than the others.

Otherwise (when using the built-in speaker), all three channels are mixed at the same intensity. This signal appears to be also sent to the Tape output line also, so a connected Data Recorder could be used to record CPC music also.

 

== BASIC Sound Test ==

You can test the PSG sound channels by typing simple SOUND commands in BASIC. You should hear a 440Hz sound for 10 seconds at full volume for each of these commands:

SOUND 1,142,1000,15 should produce sound in the left speaker. (channel A)
SOUND 2,142,1000,15 should produce sound in both speakers. (channel B)
SOUND 4,142,1000,15 should produce sound in the right speaker. (channel C)

 

== Block Diagram ==
*[[File:PSG Block Diagram.png]]

Much like the [[CRTC]] chip, the PSG consists of a few simple functional blocks consisting of counters, equality comparators and some fairly simple logic.

Careful studies of the chip output prove that the chip '''counts up''' from 0 until the counter becomes '''greater or equal''' to the period, at which point the output flips and the counter resets to 0. (This means that shortening the period can cause an immediate flip if the phase counter is already past the new period value.)

This is an important difference when the program is rapidly changing the period to modulate the sound. This is worthwhile noting, since the datasheets say that the chip counts down.

Also, note that period = 0 is the same as period = 1. This is mentioned in the YM2203 datasheet. However, this does NOT apply to the Envelope period. In that case, period = 0 is half as period = 1. [https://github.com/mamedev/mame/blob/master/src/devices/sound/ay8910.cpp Source] (Does this last sentence apply only to the SSG or to the PSG as well?)

The tones, the noise, and envelope are never halted. All of them are continually active whether or not they're connected to an audible output.

Things that have been verified not to halt things: [https://forums.nesdev.org/viewtopic.php?p=236745#p236745 Source]
* Volume 0 does not halt tone or noise
* Tone disable bit does not halt tone
* Setting all 3 noise disable bits does not halt noise
* Clearing all 3 channel volume envelope bits does not halt envelope
* Period value of 0 does not halt any of these (treated as period 1 in all cases)

 

== Schematics ==

The PSG is driven by an external clock at 1MHz provided by the [[Gate Array]].
The AY chip has an internal clock divider by 8 which means that it works internally at 125KHz, outputting 125,000 samples per second for each channel.

The BC2 and A8 pins are always equal to 1 as they are connected to +5V.
The /A9 pin is non-existent on the AY-3-8912 model.

On the Amstrad CPC 6128 chassis diagram, we can see how the 3 channels of the PSG are mixed to the stereo jack (with channel B being split in half between the left and right output). And the 3 channels being mixed in equal parts to mono for the speaker and tape port. [https://www.cpcwiki.eu/imgs/4/4a/CPC6128_Schematic.png Source]

 

== Chip Variants ==

=== IC models used in CPC ===

These are the ones known to be used in the CPC by looking at pictures of CPC mainboards. All should operate almost identically.

* GI AY-3-8912 [https://www.cpcwiki.eu/imgs/c/cc/CPC464_PCB_Top_%28Z70378_MC0046A%29.jpg Source]
* GI AY-3-8912A [https://www.cpcwiki.eu/imgs/f/f1/CPC6128_PCB_Top_%28Z70290_MC0020B%29.jpg Source]
* Microchip AY-3-8912 [https://www.cpcwiki.eu/imgs/c/cf/AmstradCPC464_Z70375_MC0044D_GA40010_PCB_Top.jpg Source]
* Microchip AY38912/P [https://www.cpcwiki.eu/imgs/5/5e/CPC464Plus_MC0122B_2700-016P-3_PCB_Top.jpg Source]

=== Other Variants ===

The PSG chip family is composed of 3 variants:
* the AY-3-8910, with two 8-bit I/O ports and a 40-pin package
* the AY-3-8912, with one 8-bit I/O port and a 28-pin package
* the AY-3-8913, with no I/O port and a 24-pin package
In addition to the CPC, these chips were also used in the [[KC Compact]], [[ZX Spectrum]], [[MSX]], [[Oric-1/Atmos|Oric]], [[EG2000 Colour Genie]], [[Vectrex]], [[Intellivision]] and in the Mockingboard expansion for the [[Apple II]].

There are also PSG clones: Toshiba T7766A, Winbond WF19054, JFC 95101 and File KC89C72. [https://wiki.agiri.ninja/sound_chip_clones:index Source]

Yamaha produced the SSG (Software-controlled Sound Generator) chip family (YM2149F, YM3439, YMZ294, YMZ284, YMZ285) which is a quasi-clone of the PSG. The main difference is that the envelope counter on the PSG has 16 steps. On the SSG it has twice the steps, happening twice as fast. This chip equips the [[Atari ST]], [[Aleste 520EX]] and [https://www.msx.org/wiki/Yamaha_YM2149 some MSX computers]. It is also used in the [[PlayCity]] expansion.

The SSG has also been integrated as a component inside some of the arcade soundchips of the Yamaha OPN family. That's why you can find it in the [[Neo-Geo]] as a component inside the YM2610 soundchip. And the same is true for the OPN3 soundchip of the [[Play2CPC]] expansion.

The chip is clocked differently depending on the computer: ZX Spectrum: 1773400 Hz ; Pentagon: 1750000 Hz ; MSX: 1789772 Hz ; CPC: 1000000 Hz ; Oric: 1000000 Hz ; Atari ST: 2000000 Hz.

The EPSG (AY-3-8930), used in the Covox Sound Master soundcard on PCs, is a register-compatible evolution of the AY-3-8910:
* The pulse width can be changed from square to 8 other duty cycles
* There are 3 independent envelope generators, 1 for each channel
* The amplitude control is more accurate (5-bit instead of 4-bit)
* The tone period setting is more accurate (16-bit instead of 12-bit)
* The noise period setting is more accurate (8-bit instead of 5-bit)
* The noise tone can be changed by applying an AND and OR mask to the output

=== Competitors ===

The PSG chip competed with the DCSG (Digital Complex Sound Generator) chip family (SN76489, SN94624, TMS9919) by Texas Instruments.

The DCSG has similar sounding features except that it does not have any envelope control and that its noise generator has its own dedicated channel.

=== Replacing the AY-3-8912 in the CPC with an AY-3-8910(A) ===

In case that the AY-3-8912 needs to be replaced in the CPC it can become a hurdle these days to get a real AY-3-8912 especially for an acceptable price.

Instead of the original AY-3-8912 it's possible to use an AY-3-8910(A) instead with the help of a small adapter board. An open source adapter board can be found here: https://github.com/etomuc/CPC-AY-3-8910-to-8912-adapter

For tips regarding the desoldering of ICs see this Wiki page: [[IC Repair]]

 

== Links ==
*[http://en.wikipedia.org/wiki/General_Instrument_AY-3-8910 Wikipedia on the PSG]
*[[Media:Ay3-891x.pdf|AY-3-891x datasheet]] [[Media:Ym2149 datasheet.pdf|YM2149 datasheet]]
*[http://quasar.cpcscene.net/doku.php?id=assem:psg Quasar PSG documentation (in french)]
*[https://youtu.be/C4ezcX1W2_Y Mix I] [https://youtu.be/gH57xU9c7dE Mix II] [https://youtu.be/e7V3EMXF97g Mix III] AMSTRAD CPC MUSIC 1 hour
*[https://youtu.be/AhgUwqv2yAE Space Debris - Amstrad CPC Soundtrakker cover] [https://youtu.be/E_plcHyOC_8 RUN! - SID emulation on Amstrad CPC] by [[BSC]]
*[https://nguillaumin.github.io/ym-jukebox/ YM Jukebox] [https://ym.mmcm.ru/ AY Music Collection]

 

[[Category:Hardware]]
[[Category:Music and sound]]
[[Category:CPC Internal Components]]

CPC iRAM

2025-09-23T22:49:13Z

Eto:

[[File:Iram640.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

== released ==

=== CPC 6128 - iRAM/640 ===

<gallery>
Iram640.jpeg|iRAM/640
Iram640 builtin.jpeg|iRAM/640 built-in
Iram640ramtest.jpeg|RAM Test
</gallery>

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC 6128 - iRAM/1088 ===

<gallery>
iRAM1088.jpg|iRAM/1088 for CPC 6128
</gallery>

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

== currently in development ==

=== CPC 464/664 - iRAM/1024 ===

<gallery>
iRAM1024.jpg|iRAM/1024 for CPC 464/664
iRAM1024symbos.jpg|SymbOS on CPC 464
</gallery>

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, final PCB design will be tested, will be released in late 2025

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC 6128 - iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC 464/664 - iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC 6128 - iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC 464/664 - iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

File:IRAM1024symbos.jpg

2025-09-23T22:40:39Z

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File:IRAM1024.jpg

2025-09-23T22:40:13Z

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File:IRAM1088.jpg

2025-09-23T22:39:20Z

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CPC iRAM

2025-09-23T22:17:24Z

Eto:

[[File:Iram640.jpeg|thumbnail]]
[[File:Iram640 builtin.jpeg|thumbnail]]
[[File:Iram640ramtest.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

== released ==

=== CPC iRAM/640 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

=== CPC iRAM/1088 ===

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-1088

== currently in development ==

=== CPC iRAM/1024 ===

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, final PCB design will be tested, will be released in late 2025

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF1504)

Status: just an idea

== abandoned ==

=== CPC iRAM/640s ===

* minified iRAM/640
* for CPC 6128
* size just a tiny bit bigger than Z80 CPU socket
* TSSOP SMD components below Z80
* requires good soldering skills and special tools to program SMD CPLDs

Status: fully designed, abandoned as it offers no advantage over DIY friendly version and would only benefit commercial sellers
(Hint: Lotharek offers a similar expansion commercially for a good price)

=== CPC iRAM/1024s ===

* smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype

=== CPC iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

LCD monitor and LCD TV Solution (RGB)

2025-09-11T08:27:06Z

Eto: /* Links */

Generally speaking, it's not too hard to connect the CPC to a modern LCD TV or monitor. Either the monitor already supports the CPC's signal directly, like TVs with SCART or RGB connector often do, or you can use one of the many converters that accept the RGB signal and convert it to a more modern signal, like VGA or HDMI.

If you are looking how to produce a Composite Sync signal, check [[LCD And Plasma TV Solution]].

== The Pitfalls of LCDs ==

One thing to keep in mind is, that there is yet no really perfect replacement for a CRT. There are mainly four issues, that will be different with an LCD.

=== Pitfall #1: power adapter ===

If you want to connect the CPC to anything but an Amstrad monitor you also need to provide a new power adapter, as the CPC does not have its own power adapter and relied on its original monitor. More information about this can be found in the article [[Power Supply for CPC and CPC plus]].

=== Pitfall #2: Screen lag ===

Once you connect the CPC to a modern monitor, you may experience a phenomenon, that some games just don't feel right. It's like you are too slow - or that the collision detection seems to be off. Of course, some games are just crappy in that regard, or you might just get old ;-). But it's at least as likely, that your set-up has a significant screen lag. Screen lag means, that there is a significant delay between the moment that your CPC sends a signal to the monitor and the moment that this signal is shown on screen. Old school monitors don't have a significant screen lag. The CPC updates its screen 50 times per second, and any update will be visible almost instantly on a CTM644, GT65 or any other old school monitor with a tube. the reason for this is, that these monitors work analogue. They display the signals they receive immediately. As soon as there are any digital devices involved, this changes. Digital devices have some kind of chips that take the analogue signal and transform them into digital signals. This transformation requires some time and depending on the logic that is built in, this time is almost neglectable - or can be so significant, that it harms your gaming experience. A lag of 1 or 2 frames often does not do any harm, but any lag above one or two frames can be recognisable, at least in fast paced games which you are familiar with. You will see bullets still quite a distance away from you, but in the computer, the bullets have already hit you. You simply can no longer react fast enough, so this might be even [https://www.youtube.com/watch?v=7VOsOuQ5mhM&t=12s THE most important aspect of your set-up].

(Note: Screen lag of course is not limited to games, but primarily there it can become a problem. If you want to measure the screen-lag of your set-up, there is a pretty easy way to do so, you just need your CPC, a mobile phone that can shoot videos at 120 or 240fps and a computer, to watch that video frame per frame. See: [[Testing your Screen-Lag with a CPC]])

=== Pitfall #3: CRTC tricks ===

Not all demos and games will work if you are using an LCD. Games and demos that push the limit of the CPC, especially with CRTC tricks, might not work with a modern LCD. Relentless is a famous example, that (at the point of writing this article) will only work on real CRT monitors (or emulators of course). Although this sounds like a huge drawback, on a daily basis, it's not as bad. With the right set-up, except for a few exceptions like Relentless, all games and even most demos will work perfectly or in a way, that you don't experience problems.

=== Pitfall #4: pixel mask ===

(colour) CRTs have a pixel mask to produce red, green and blue from a single electronic beam. On a CRT there is no such thing as a sharp pixel. When you compare the same picture on a CRT and a LCD, you will see, that the picture on the CRT is much more blurry - but also smoother. It's personal preference if you like one more or the other. Or you don't bother. But some people would never replace their beloved CRT for an LCD, just because of the pixel mask.

{|
|-
| [[File:ModernLCD AsphaltCRT.JPG|thumbnail|none|Pixel mask of a CRT]] || [[File:ModernLCD AsphaltLCD.JPG|thumbnail|none|The same game on a LCD]]
|}

== How to connect to a modern LCD ==

The CPC monitor connector offers 3 lines for the colours red, green and blue, and one line for a composite sync (csync) signal, that combines horizontal and vertical sync. The horizontal frequency is 15.6Khz and the vertical frequency is 50Hz. In short: If your monitor supports RGB and these frequency values, you can use your monitor with a simple, passive adapter. If not, you need an active converter.

=== Options with passive adapters ===

==== LCD TV sets (SCART) ====

Many LCD TV sets offer a SCART connector, which often accepts the CPC signal directly. All you need is a [[TV SCART cable|CPC-to-Scart cable]] that you can either build yourself, or buy on Ebay for not too much money. Especially if you want a distinct monitor for your retro corner anyway, this can be a pretty nice and cheap solution. Used 15" camping TV sets have just the right size to feel comfortable and can be bought for a few bucks on Ebay or your local classifieds.

Your only enemy here is: screen lag. Some of the LCD TVs perform almost like CRTs, others seem to include a SCART2HDMI converter, and they have a bad lag (see below).

==== LCD computer monitors (VGA) ====

Some VGA LCD monitors are know to support the 15.6kHz frequency. These often can be connected with a simple DIN to VGA adapter. Screen lag of LCD monitors is usually very good and close to non-existing or half a frame max.

For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

A known example for a perfectly working monitor is the BENQ 702A. More examples can be found on the internet (see links below), but be aware, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. In those cases, [[Connecting the CPC to a VGA monitor - CPC2VGA|an adapter, that splits c-sync into h-sync and v-sync (CPC2VGA)]] would be required.

=== Converter options ===

There are plenty of active converters to connect retro computers and consoles to modern TVs and monitors. Their biggest difference is performance and price. And if you are not willing to do a bit of soldering, you probably will end up with either spending a lot of money - or getting a bad solution.

==== SCART to HDMI converters ====

SCART to HDMI converters are the cheapest and most simple solution. Make sure they (really) support RGB and not only composite video, like the cheapest SCART to HDMI converters usually do. RGB SCART converters start at around 40€ (2025). They will usually work and you will probably first think, that this is perfect, but they can add a hefty lag to your screen, some add up to 120ms (or 6 frames). Also CRTC tricks often do not work so some games won't be playable.

[[File:ModernLCD Scart2HDMI.JPG|thumbnail|none|Typical Scart2HDMI box]]

This Youtube video explains in detail why you should [https://youtu.be/7VOsOuQ5mhM?t=587 avoid Scart to HDMI converters for retro gaming].

It's fine if you only want to do a bit of BASIC programming or play adventures, but it could do some harm to fast action games.

==== Sega Genesis/Megadrive to HDMI converters ====

Those are similar to Scart to HDMI converters and can be a bit cheaper and are much smaller. However their connector is made for SEGA consoles so you will need mod it or build your own adapter to connect it to the CPC.

Pay attention to buy an adapter that supports RGB as some only support Composite Video.

Most adapters will not support advanced CRTC tricks like in Relentless or even Ghosts'n Goblins. However the "[https://kaicolabs.com/product/kaico-sega-saturn-2x-line-doubler-hdmi/ Kaico Sega Saturn 2x]" adapter does properly support CRTC scrolling like in Ghosts'n Goblins - only the very latest, advanced tricks like in Relentless will not fully work but at least display a picture with stuttered scrolling. You might need to update the firmware and adjust brightness settings with the software from the Kaicolabs homepage to properly use it. The adapter can be found for around €30 in online stores (as of 2025).

Another advantage: The adapters are so small that they can easily be placed inside the CPC to add an internal HDMI output.

==== Scan converters ====

===== Framemeister / OSSC =====

There are quite a few scan converters specifically built to connect many (all) retro computers and consoles to modern screens. The most famous ones are probably Framemeister and [https://junkerhq.net/xrgb/index.php?title=OSSC Open Source Screen Converter (OSSC)]. They are very flexible, have lots of options, zero or very low lag - and are really or quite expensive. Actually the only disadvantage they have is, that they are expensive. If you have a big retro collection, with several machines and consoles that you want to hook up to your LCD, then one of those might be the right choice. If not, there are cheaper, still great alternatives.

===== GBS8200 (VGA) / HD-VC9900 (HDMI) =====

These converters have originally been made to convert signals of arcade boards to modern LCD monitors via VGA (GBS8200) or HDMI (VC9900).

[[File:ModernLCD GBS8200GBSControl.JPG|thumbnail|none|GBS 8200 with GBS Control mod]]

They do support the signal of the CPC but without any further modification, the conversion quality is limited. It adds up to 2 frames of lag, which might be just acceptable, but many famous games and demos won't work due to synching problems. All this improves a lot, once you add the GBS control mod to it. That's basically adding a microcontroller to the original board, that takes over control and adds features and flexibility that are [https://www.youtube.com/watch?v=fmfR0XI5czI&t=879s close to the Framemeister and OSSC]. Also the lag shrinks down to [https://www.youtube.com/watch?v=fmfR0XI5czI&t=783s less than a frame], at least if your monitor does not add much lag on top.

See [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200] and [https://github.com/ramapcsx2/gbs-control/issues/165 VC9900]

Especially the GBS8200 is easily available and incredibly cheap and if you know how to solder, the GBS Control mod is easy to do. And that's of course also the downside: you need to solder - and probably also 3D print a case for the GBS.

Update: Some sellers have adopted the GBS Control firmware and offer full products based on the GBS 8200 chipsets and the GBS Control mod. The price is a bit more than building one yourself - but still A LOT cheaper than any other (good) scaler solution. On the positive side it also already includes a case and HDMI output. Offers can be found e.g. on Amazon or AliExpress. Search for "GBS Control". No test has been docuemted so far with a CPC, so there's still a risk that the hardware behaves differently from a self-built GBS mod.

===== RGB2HDMI =====

[https://www.youtube.com/watch?v=2CnsQBGAuos The new star on the horizon.] An open source project, that combines a Raspberry Pi with some custom logic, to convert signals from home computers and home consoles to HDMI. For almost every computer there is a more or less different version of the board. You can build the RGB2HDMI yourself or buy a finished version, e.g. on sellmyretro.com . It's features are even beyond those of the OSSC and Framemeister. Its total price is somewhere between the GBS and the OSSC, depending on where you buy it. And its tiny. Its biggest disadvantage is, that you need a different version of the board per console or home computer (well - some computers share a similar signal, so e.g. for the BBC you can also use the CPC version, but e.g. an Amiga or an Amstrad Plus each need another converter version). Screen lag has not been measured yet for it, but it seems to be very low.

===== vga4cpc =====

This DIY project by forum user gregg is based on the Raspberry Pico and (as of November 2024) the only solution that supports most (all?) CRTC tricks. Even games like Relentless that do not render properly on any of the other scan doublers are perfectly playable and absolutely smooth. Hardware and software are publicly available and the scan doubler can be built for less than €30 (€10-€30, depending on shipping costs for the parts). Assembly should be doable for anyone with average soldering skills.

Github project: https://github.com/grzegorz-gr/vga4cpc

Forum thread: https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/vga-through-rpi-pico-how-many-colors-possible-on-border/

The only downside would be that it only supports the Amstrad CPC, so if you own other computers (or even a Amstrad Plus or GX4000), you still need another solution.

{|
|-
| [[File:Vga4cpc.jpg|thumbnail]] || [[File:Picovgacase.jpg|thumbnail]]
|}

''Eto''

== Links ==

CPC Wiki

* [[TV_SCART_cable|How to - Scart cables]]
* [[LCD And Plasma TV Solution]] (Composite Video)
* [[Power Supply for CPC and CPC plus]]

External

* [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200]
* [https://www.youtube.com/watch?v=7VOsOuQ5mhM Screen Lag - explanation and comparison video]
* [https://15khz.miraheze.org/wiki/Main_Page List of 15kHz compatible monitors]
* https://15khz.net similar list

[[Category:Hardware]] [[Category:Peripherals]] [[Category:DIY]] [[Category:Graphic]]

LCD monitor and LCD TV Solution (RGB)

2025-09-11T08:24:02Z

Eto: /* Sega Genesis/Megadrive to HDMI converters */

Generally speaking, it's not too hard to connect the CPC to a modern LCD TV or monitor. Either the monitor already supports the CPC's signal directly, like TVs with SCART or RGB connector often do, or you can use one of the many converters that accept the RGB signal and convert it to a more modern signal, like VGA or HDMI.

If you are looking how to produce a Composite Sync signal, check [[LCD And Plasma TV Solution]].

== The Pitfalls of LCDs ==

One thing to keep in mind is, that there is yet no really perfect replacement for a CRT. There are mainly four issues, that will be different with an LCD.

=== Pitfall #1: power adapter ===

If you want to connect the CPC to anything but an Amstrad monitor you also need to provide a new power adapter, as the CPC does not have its own power adapter and relied on its original monitor. More information about this can be found in the article [[Power Supply for CPC and CPC plus]].

=== Pitfall #2: Screen lag ===

Once you connect the CPC to a modern monitor, you may experience a phenomenon, that some games just don't feel right. It's like you are too slow - or that the collision detection seems to be off. Of course, some games are just crappy in that regard, or you might just get old ;-). But it's at least as likely, that your set-up has a significant screen lag. Screen lag means, that there is a significant delay between the moment that your CPC sends a signal to the monitor and the moment that this signal is shown on screen. Old school monitors don't have a significant screen lag. The CPC updates its screen 50 times per second, and any update will be visible almost instantly on a CTM644, GT65 or any other old school monitor with a tube. the reason for this is, that these monitors work analogue. They display the signals they receive immediately. As soon as there are any digital devices involved, this changes. Digital devices have some kind of chips that take the analogue signal and transform them into digital signals. This transformation requires some time and depending on the logic that is built in, this time is almost neglectable - or can be so significant, that it harms your gaming experience. A lag of 1 or 2 frames often does not do any harm, but any lag above one or two frames can be recognisable, at least in fast paced games which you are familiar with. You will see bullets still quite a distance away from you, but in the computer, the bullets have already hit you. You simply can no longer react fast enough, so this might be even [https://www.youtube.com/watch?v=7VOsOuQ5mhM&t=12s THE most important aspect of your set-up].

(Note: Screen lag of course is not limited to games, but primarily there it can become a problem. If you want to measure the screen-lag of your set-up, there is a pretty easy way to do so, you just need your CPC, a mobile phone that can shoot videos at 120 or 240fps and a computer, to watch that video frame per frame. See: [[Testing your Screen-Lag with a CPC]])

=== Pitfall #3: CRTC tricks ===

Not all demos and games will work if you are using an LCD. Games and demos that push the limit of the CPC, especially with CRTC tricks, might not work with a modern LCD. Relentless is a famous example, that (at the point of writing this article) will only work on real CRT monitors (or emulators of course). Although this sounds like a huge drawback, on a daily basis, it's not as bad. With the right set-up, except for a few exceptions like Relentless, all games and even most demos will work perfectly or in a way, that you don't experience problems.

=== Pitfall #4: pixel mask ===

(colour) CRTs have a pixel mask to produce red, green and blue from a single electronic beam. On a CRT there is no such thing as a sharp pixel. When you compare the same picture on a CRT and a LCD, you will see, that the picture on the CRT is much more blurry - but also smoother. It's personal preference if you like one more or the other. Or you don't bother. But some people would never replace their beloved CRT for an LCD, just because of the pixel mask.

{|
|-
| [[File:ModernLCD AsphaltCRT.JPG|thumbnail|none|Pixel mask of a CRT]] || [[File:ModernLCD AsphaltLCD.JPG|thumbnail|none|The same game on a LCD]]
|}

== How to connect to a modern LCD ==

The CPC monitor connector offers 3 lines for the colours red, green and blue, and one line for a composite sync (csync) signal, that combines horizontal and vertical sync. The horizontal frequency is 15.6Khz and the vertical frequency is 50Hz. In short: If your monitor supports RGB and these frequency values, you can use your monitor with a simple, passive adapter. If not, you need an active converter.

=== Options with passive adapters ===

==== LCD TV sets (SCART) ====

Many LCD TV sets offer a SCART connector, which often accepts the CPC signal directly. All you need is a [[TV SCART cable|CPC-to-Scart cable]] that you can either build yourself, or buy on Ebay for not too much money. Especially if you want a distinct monitor for your retro corner anyway, this can be a pretty nice and cheap solution. Used 15" camping TV sets have just the right size to feel comfortable and can be bought for a few bucks on Ebay or your local classifieds.

Your only enemy here is: screen lag. Some of the LCD TVs perform almost like CRTs, others seem to include a SCART2HDMI converter, and they have a bad lag (see below).

==== LCD computer monitors (VGA) ====

Some VGA LCD monitors are know to support the 15.6kHz frequency. These often can be connected with a simple DIN to VGA adapter. Screen lag of LCD monitors is usually very good and close to non-existing or half a frame max.

For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

A known example for a perfectly working monitor is the BENQ 702A. More examples can be found on the internet (see links below), but be aware, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. In those cases, [[Connecting the CPC to a VGA monitor - CPC2VGA|an adapter, that splits c-sync into h-sync and v-sync (CPC2VGA)]] would be required.

=== Converter options ===

There are plenty of active converters to connect retro computers and consoles to modern TVs and monitors. Their biggest difference is performance and price. And if you are not willing to do a bit of soldering, you probably will end up with either spending a lot of money - or getting a bad solution.

==== SCART to HDMI converters ====

SCART to HDMI converters are the cheapest and most simple solution. Make sure they (really) support RGB and not only composite video, like the cheapest SCART to HDMI converters usually do. RGB SCART converters start at around 40€ (2025). They will usually work and you will probably first think, that this is perfect, but they can add a hefty lag to your screen, some add up to 120ms (or 6 frames). Also CRTC tricks often do not work so some games won't be playable.

[[File:ModernLCD Scart2HDMI.JPG|thumbnail|none|Typical Scart2HDMI box]]

This Youtube video explains in detail why you should [https://youtu.be/7VOsOuQ5mhM?t=587 avoid Scart to HDMI converters for retro gaming].

It's fine if you only want to do a bit of BASIC programming or play adventures, but it could do some harm to fast action games.

==== Sega Genesis/Megadrive to HDMI converters ====

Those are similar to Scart to HDMI converters and can be a bit cheaper and are much smaller. However their connector is made for SEGA consoles so you will need mod it or build your own adapter to connect it to the CPC.

Pay attention to buy an adapter that supports RGB as some only support Composite Video.

Most adapters will not support advanced CRTC tricks like in Relentless or even Ghosts'n Goblins. However the "[https://kaicolabs.com/product/kaico-sega-saturn-2x-line-doubler-hdmi/ Kaico Sega Saturn 2x]" adapter does properly support CRTC scrolling like in Ghosts'n Goblins - only the very latest, advanced tricks like in Relentless will not fully work but at least display a picture with stuttered scrolling. You might need to update the firmware and adjust brightness settings with the software from the Kaicolabs homepage to properly use it. The adapter can be found for around €30 in online stores (as of 2025).

Another advantage: The adapters are so small that they can easily be placed inside the CPC to add an internal HDMI output.

==== Scan converters ====

===== Framemeister / OSSC =====

There are quite a few scan converters specifically built to connect many (all) retro computers and consoles to modern screens. The most famous ones are probably Framemeister and [https://junkerhq.net/xrgb/index.php?title=OSSC Open Source Screen Converter (OSSC)]. They are very flexible, have lots of options, zero or very low lag - and are really or quite expensive. Actually the only disadvantage they have is, that they are expensive. If you have a big retro collection, with several machines and consoles that you want to hook up to your LCD, then one of those might be the right choice. If not, there are cheaper, still great alternatives.

===== GBS8200 (VGA) / HD-VC9900 (HDMI) =====

These converters have originally been made to convert signals of arcade boards to modern LCD monitors via VGA (GBS8200) or HDMI (VC9900).

[[File:ModernLCD GBS8200GBSControl.JPG|thumbnail|none|GBS 8200 with GBS Control mod]]

They do support the signal of the CPC but without any further modification, the conversion quality is limited. It adds up to 2 frames of lag, which might be just acceptable, but many famous games and demos won't work due to synching problems. All this improves a lot, once you add the GBS control mod to it. That's basically adding a microcontroller to the original board, that takes over control and adds features and flexibility that are [https://www.youtube.com/watch?v=fmfR0XI5czI&t=879s close to the Framemeister and OSSC]. Also the lag shrinks down to [https://www.youtube.com/watch?v=fmfR0XI5czI&t=783s less than a frame], at least if your monitor does not add much lag on top.

See [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200] and [https://github.com/ramapcsx2/gbs-control/issues/165 VC9900]

Especially the GBS8200 is easily available and incredibly cheap and if you know how to solder, the GBS Control mod is easy to do. And that's of course also the downside: you need to solder - and probably also 3D print a case for the GBS.

Update: Some sellers have adopted the GBS Control firmware and offer full products based on the GBS 8200 chipsets and the GBS Control mod. The price is a bit more than building one yourself - but still A LOT cheaper than any other (good) scaler solution. On the positive side it also already includes a case and HDMI output. Offers can be found e.g. on Amazon or AliExpress. Search for "GBS Control". No test has been docuemted so far with a CPC, so there's still a risk that the hardware behaves differently from a self-built GBS mod.

===== RGB2HDMI =====

[https://www.youtube.com/watch?v=2CnsQBGAuos The new star on the horizon.] An open source project, that combines a Raspberry Pi with some custom logic, to convert signals from home computers and home consoles to HDMI. For almost every computer there is a more or less different version of the board. You can build the RGB2HDMI yourself or buy a finished version, e.g. on sellmyretro.com . It's features are even beyond those of the OSSC and Framemeister. Its total price is somewhere between the GBS and the OSSC, depending on where you buy it. And its tiny. Its biggest disadvantage is, that you need a different version of the board per console or home computer (well - some computers share a similar signal, so e.g. for the BBC you can also use the CPC version, but e.g. an Amiga or an Amstrad Plus each need another converter version). Screen lag has not been measured yet for it, but it seems to be very low.

===== vga4cpc =====

This DIY project by forum user gregg is based on the Raspberry Pico and (as of November 2024) the only solution that supports most (all?) CRTC tricks. Even games like Relentless that do not render properly on any of the other scan doublers are perfectly playable and absolutely smooth. Hardware and software are publicly available and the scan doubler can be built for less than €30 (€10-€30, depending on shipping costs for the parts). Assembly should be doable for anyone with average soldering skills.

Github project: https://github.com/grzegorz-gr/vga4cpc

Forum thread: https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/vga-through-rpi-pico-how-many-colors-possible-on-border/

The only downside would be that it only supports the Amstrad CPC, so if you own other computers (or even a Amstrad Plus or GX4000), you still need another solution.

{|
|-
| [[File:Vga4cpc.jpg|thumbnail]] || [[File:Picovgacase.jpg|thumbnail]]
|}

''Eto''

== Links ==

CPC Wiki

* [[TV_SCART_cable|How to - Scart cables]]
* [[LCD And Plasma TV Solution]] (Composite Video)
* [[Power Supply for CPC and CPC plus]]

External

* [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200]
* [https://www.youtube.com/watch?v=7VOsOuQ5mhM Screen Lag - explanation and comparison video]
* [http://15khz.wikidot.com List of 15kHz compatible monitors]
* https://15khz.net similar list

[[Category:Hardware]] [[Category:Peripherals]] [[Category:DIY]] [[Category:Graphic]]

LCD monitor and LCD TV Solution (RGB)

2025-09-08T14:20:33Z

Eto: /* SCART to HDMI converters */

Generally speaking, it's not too hard to connect the CPC to a modern LCD TV or monitor. Either the monitor already supports the CPC's signal directly, like TVs with SCART or RGB connector often do, or you can use one of the many converters that accept the RGB signal and convert it to a more modern signal, like VGA or HDMI.

If you are looking how to produce a Composite Sync signal, check [[LCD And Plasma TV Solution]].

== The Pitfalls of LCDs ==

One thing to keep in mind is, that there is yet no really perfect replacement for a CRT. There are mainly four issues, that will be different with an LCD.

=== Pitfall #1: power adapter ===

If you want to connect the CPC to anything but an Amstrad monitor you also need to provide a new power adapter, as the CPC does not have its own power adapter and relied on its original monitor. More information about this can be found in the article [[Power Supply for CPC and CPC plus]].

=== Pitfall #2: Screen lag ===

Once you connect the CPC to a modern monitor, you may experience a phenomenon, that some games just don't feel right. It's like you are too slow - or that the collision detection seems to be off. Of course, some games are just crappy in that regard, or you might just get old ;-). But it's at least as likely, that your set-up has a significant screen lag. Screen lag means, that there is a significant delay between the moment that your CPC sends a signal to the monitor and the moment that this signal is shown on screen. Old school monitors don't have a significant screen lag. The CPC updates its screen 50 times per second, and any update will be visible almost instantly on a CTM644, GT65 or any other old school monitor with a tube. the reason for this is, that these monitors work analogue. They display the signals they receive immediately. As soon as there are any digital devices involved, this changes. Digital devices have some kind of chips that take the analogue signal and transform them into digital signals. This transformation requires some time and depending on the logic that is built in, this time is almost neglectable - or can be so significant, that it harms your gaming experience. A lag of 1 or 2 frames often does not do any harm, but any lag above one or two frames can be recognisable, at least in fast paced games which you are familiar with. You will see bullets still quite a distance away from you, but in the computer, the bullets have already hit you. You simply can no longer react fast enough, so this might be even [https://www.youtube.com/watch?v=7VOsOuQ5mhM&t=12s THE most important aspect of your set-up].

(Note: Screen lag of course is not limited to games, but primarily there it can become a problem. If you want to measure the screen-lag of your set-up, there is a pretty easy way to do so, you just need your CPC, a mobile phone that can shoot videos at 120 or 240fps and a computer, to watch that video frame per frame. See: [[Testing your Screen-Lag with a CPC]])

=== Pitfall #3: CRTC tricks ===

Not all demos and games will work if you are using an LCD. Games and demos that push the limit of the CPC, especially with CRTC tricks, might not work with a modern LCD. Relentless is a famous example, that (at the point of writing this article) will only work on real CRT monitors (or emulators of course). Although this sounds like a huge drawback, on a daily basis, it's not as bad. With the right set-up, except for a few exceptions like Relentless, all games and even most demos will work perfectly or in a way, that you don't experience problems.

=== Pitfall #4: pixel mask ===

(colour) CRTs have a pixel mask to produce red, green and blue from a single electronic beam. On a CRT there is no such thing as a sharp pixel. When you compare the same picture on a CRT and a LCD, you will see, that the picture on the CRT is much more blurry - but also smoother. It's personal preference if you like one more or the other. Or you don't bother. But some people would never replace their beloved CRT for an LCD, just because of the pixel mask.

{|
|-
| [[File:ModernLCD AsphaltCRT.JPG|thumbnail|none|Pixel mask of a CRT]] || [[File:ModernLCD AsphaltLCD.JPG|thumbnail|none|The same game on a LCD]]
|}

== How to connect to a modern LCD ==

The CPC monitor connector offers 3 lines for the colours red, green and blue, and one line for a composite sync (csync) signal, that combines horizontal and vertical sync. The horizontal frequency is 15.6Khz and the vertical frequency is 50Hz. In short: If your monitor supports RGB and these frequency values, you can use your monitor with a simple, passive adapter. If not, you need an active converter.

=== Options with passive adapters ===

==== LCD TV sets (SCART) ====

Many LCD TV sets offer a SCART connector, which often accepts the CPC signal directly. All you need is a [[TV SCART cable|CPC-to-Scart cable]] that you can either build yourself, or buy on Ebay for not too much money. Especially if you want a distinct monitor for your retro corner anyway, this can be a pretty nice and cheap solution. Used 15" camping TV sets have just the right size to feel comfortable and can be bought for a few bucks on Ebay or your local classifieds.

Your only enemy here is: screen lag. Some of the LCD TVs perform almost like CRTs, others seem to include a SCART2HDMI converter, and they have a bad lag (see below).

==== LCD computer monitors (VGA) ====

Some VGA LCD monitors are know to support the 15.6kHz frequency. These often can be connected with a simple DIN to VGA adapter. Screen lag of LCD monitors is usually very good and close to non-existing or half a frame max.

For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

A known example for a perfectly working monitor is the BENQ 702A. More examples can be found on the internet (see links below), but be aware, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. In those cases, [[Connecting the CPC to a VGA monitor - CPC2VGA|an adapter, that splits c-sync into h-sync and v-sync (CPC2VGA)]] would be required.

=== Converter options ===

There are plenty of active converters to connect retro computers and consoles to modern TVs and monitors. Their biggest difference is performance and price. And if you are not willing to do a bit of soldering, you probably will end up with either spending a lot of money - or getting a bad solution.

==== SCART to HDMI converters ====

SCART to HDMI converters are the cheapest and most simple solution. Make sure they (really) support RGB and not only composite video, like the cheapest SCART to HDMI converters usually do. RGB SCART converters start at around 40€ (2025). They will usually work and you will probably first think, that this is perfect, but they can add a hefty lag to your screen, some add up to 120ms (or 6 frames). Also CRTC tricks often do not work so some games won't be playable.

[[File:ModernLCD Scart2HDMI.JPG|thumbnail|none|Typical Scart2HDMI box]]

This Youtube video explains in detail why you should [https://youtu.be/7VOsOuQ5mhM?t=587 avoid Scart to HDMI converters for retro gaming].

It's fine if you only want to do a bit of BASIC programming or play adventures, but it could do some harm to fast action games.

==== Sega Genesis/Megadrive to HDMI converters ====

Those are similar to Scart to HDMI converters and can be a bit cheaper and are much smaller. However you will need mod it or build your own adapter to connect it to the CPC.

Pay attention to buy an adapter that supports RGB as some only support Composite Video.

==== Scan converters ====

===== Framemeister / OSSC =====

There are quite a few scan converters specifically built to connect many (all) retro computers and consoles to modern screens. The most famous ones are probably Framemeister and [https://junkerhq.net/xrgb/index.php?title=OSSC Open Source Screen Converter (OSSC)]. They are very flexible, have lots of options, zero or very low lag - and are really or quite expensive. Actually the only disadvantage they have is, that they are expensive. If you have a big retro collection, with several machines and consoles that you want to hook up to your LCD, then one of those might be the right choice. If not, there are cheaper, still great alternatives.

===== GBS8200 (VGA) / HD-VC9900 (HDMI) =====

These converters have originally been made to convert signals of arcade boards to modern LCD monitors via VGA (GBS8200) or HDMI (VC9900).

[[File:ModernLCD GBS8200GBSControl.JPG|thumbnail|none|GBS 8200 with GBS Control mod]]

They do support the signal of the CPC but without any further modification, the conversion quality is limited. It adds up to 2 frames of lag, which might be just acceptable, but many famous games and demos won't work due to synching problems. All this improves a lot, once you add the GBS control mod to it. That's basically adding a microcontroller to the original board, that takes over control and adds features and flexibility that are [https://www.youtube.com/watch?v=fmfR0XI5czI&t=879s close to the Framemeister and OSSC]. Also the lag shrinks down to [https://www.youtube.com/watch?v=fmfR0XI5czI&t=783s less than a frame], at least if your monitor does not add much lag on top.

See [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200] and [https://github.com/ramapcsx2/gbs-control/issues/165 VC9900]

Especially the GBS8200 is easily available and incredibly cheap and if you know how to solder, the GBS Control mod is easy to do. And that's of course also the downside: you need to solder - and probably also 3D print a case for the GBS.

Update: Some sellers have adopted the GBS Control firmware and offer full products based on the GBS 8200 chipsets and the GBS Control mod. The price is a bit more than building one yourself - but still A LOT cheaper than any other (good) scaler solution. On the positive side it also already includes a case and HDMI output. Offers can be found e.g. on Amazon or AliExpress. Search for "GBS Control". No test has been docuemted so far with a CPC, so there's still a risk that the hardware behaves differently from a self-built GBS mod.

===== RGB2HDMI =====

[https://www.youtube.com/watch?v=2CnsQBGAuos The new star on the horizon.] An open source project, that combines a Raspberry Pi with some custom logic, to convert signals from home computers and home consoles to HDMI. For almost every computer there is a more or less different version of the board. You can build the RGB2HDMI yourself or buy a finished version, e.g. on sellmyretro.com . It's features are even beyond those of the OSSC and Framemeister. Its total price is somewhere between the GBS and the OSSC, depending on where you buy it. And its tiny. Its biggest disadvantage is, that you need a different version of the board per console or home computer (well - some computers share a similar signal, so e.g. for the BBC you can also use the CPC version, but e.g. an Amiga or an Amstrad Plus each need another converter version). Screen lag has not been measured yet for it, but it seems to be very low.

===== vga4cpc =====

This DIY project by forum user gregg is based on the Raspberry Pico and (as of November 2024) the only solution that supports most (all?) CRTC tricks. Even games like Relentless that do not render properly on any of the other scan doublers are perfectly playable and absolutely smooth. Hardware and software are publicly available and the scan doubler can be built for less than €30 (€10-€30, depending on shipping costs for the parts). Assembly should be doable for anyone with average soldering skills.

Github project: https://github.com/grzegorz-gr/vga4cpc

Forum thread: https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/vga-through-rpi-pico-how-many-colors-possible-on-border/

The only downside would be that it only supports the Amstrad CPC, so if you own other computers (or even a Amstrad Plus or GX4000), you still need another solution.

{|
|-
| [[File:Vga4cpc.jpg|thumbnail]] || [[File:Picovgacase.jpg|thumbnail]]
|}

''Eto''

== Links ==

CPC Wiki

* [[TV_SCART_cable|How to - Scart cables]]
* [[LCD And Plasma TV Solution]] (Composite Video)
* [[Power Supply for CPC and CPC plus]]

External

* [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200]
* [https://www.youtube.com/watch?v=7VOsOuQ5mhM Screen Lag - explanation and comparison video]
* [http://15khz.wikidot.com List of 15kHz compatible monitors]
* https://15khz.net similar list

[[Category:Hardware]] [[Category:Peripherals]] [[Category:DIY]] [[Category:Graphic]]

Gotek

2025-07-30T07:43:37Z

Eto: /* FlashFloppy firmware */ Keir does no longer solicit donations (since 2021 actually)

[[File:Gotek standard.jpg|thumb|right|Standard Gotek drive]]
[[File:Custom Gotek drive.jpg|thumb|right|Custom Gotek drive by [[Rodrik Studio]]]]
[[File:Gotek external.jpg|thumb|External GOTEK for a Schneider CPC 6128 with Centronics cable, 3D printed top cover and splitter cable to connect to the original 5V from the monitor]]
[[File:Gotek-internal.jpg|thumb|Internal GOTEK with 3D printed frame and 26/34 pin adapter PCB]]

== About the GOTEK ==

GOTEK is a floppy drive emulator which can be directly attached to computers instead of a normal floppy drive. The drives are popular and cheap additions to many 80s and 90s computers including the Amstrad CPC.

The basic Gotek has a 7-segment 2 digit display which shows the currently selected disk image, a USB socket for a USB memory stick, and 2 buttons to choose previous and next image.

There are additional mods that can be added:
* speaker (to simulate the sound of the read/write head stepping as heard in a real drive)
* eject button
* rotary dial (turn the dial to select the disc image)
* LCD/OLED display (this shows more information including the name of the image)

The most recent version of the GOTEK (SFRKC30.AT4.35, based on the AT32F435 chip) usually already comes with OLED display and rotary encoder but is also more expensive than the basic models.

In addition to the GOTEK you also need
* 5V power (e.g. USB power supplies will work - or you can use the monitor's 5V power output with a Y-splitter cable)
* a 34pin ribbon cable to connect it to the CPC (e.g. an old PC floppy cable which has both 3.5" and 5.25" connectors)
* connector cable to update firmware of the GOTEK (depends on firmware type)

CPC Disk images are put onto a USB drive which is plugged into the front of the Gotek. On the GOTEK a disk image is selected (via buttons or rotary encoder) and then the GOTEK behaves almost exactly as if it is a normal drive connected to the CPC with the disk being inserted.

There is only a small difference compared to a real drive with older models: the disc motor signal is not connected internally to the Gotek. This means the ready signal will be active even if the disc motor is off. The new model SFRKC30.AT4.35 can pass the motor signal and reacts (delayed if wanted) to it for the ready signal. See below for FlashFloppy firmware.

The GOTEK can replace the internal drive of the 664/6128, e.g. if the internal drive is broken. Or it can be used as the external drive B. It can even work as a 3.5" or 5.25" drive for example with Parados or VDOS.

== Firmware Update ==

Before the GOTEK can be used with the Amstrad CPC it needs to be flashed with a custom firmware.

The process depends on the type and firmware and is documented on the homepages of the respective firmwares (see below).

===HxC Floppy Emulator firmware===

There is a version of the [https://hxc2001.com HxC Floppy Emulator] firmware that can be used on the Gotek. It must be purchased from the HxC website and can then be installed and used.

The firmware supports multiple computers and their disk image formats as well as the HFE v1 & v3 file formats.

Once the firmware has been installed into a Gotek it can be updated through the USB memory stick.

===FlashFloppy firmware===

[https://github.com/keirf/FlashFloppy FlashFloppy] is probably the most popular firmware for the GOTEK. It's well supported by the author Keir Fraser and [https://github.com/keirf/flashfloppy/blob/master/COPYING completely free].

The firmware supports multiple computers and their disk image formats.

Firmware installation is more easy than HxC firmware and only needs a USB-A to USB-A cable and the use of the original software of the microcontroller vendor to install the firmware. The process is very well documented on the FlashFloppy wiki.

Once installed further updates can be performed via the USB memory stick.

On the CPC, the following FF.cfg setting can be recommended:

<pre>
# Floppy-drive interface mode
interface = shugart

# Host platform
host = unspecified

# Pins 2 & 34 output (drive->host) manual configuration
pin02 = high
pin34 = rdy

# Rotational offset of disk after a track change
track-change = realtime

# Rotational offset of disk after draining a write to Flash
write-drain = realtime

# Index pulses suppressed when RDATA and WDATA inactive?
index-suppression = yes

# Milliseconds from head-step start to RDATA active.
head-settle-ms = 12

# Milliseconds delay from motor-on to drive ready.
motor-delay = 200
</pre>

The rest of the settings can be used to your liking as they depend on preference and not on hardware emulation.

== Models ==

The best Gotek to buy currently (12/22) is the Model SFRKC30.AT4.35.

This model features a Artery AT32F435 APU and as well a motor jumper. This completes the emulation as it simulates the motor spin-up time. They are usually offered with Rotary encoder and with OLED display.

On the CPC also the AT32F415 models can be a good alternative. They are cheaper and can be upgraded with rotary encoder and OLED display.

For full details on which models to use and which to avoid, see here:
[https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]

==Physical connection==

===CPC 464 / DDI===

You can directly connect the GOTEK to the DDI-1 cable connector however you would need to cut off the noses on the bottom of the cable - or you use a short IDC extension cable to avoid cutting of the noses. Please keep in mind that the DDI-1 is powered by the original FD-1 3" drive so you still need the FD-1 or need to power the DDI-1 via an alternative method.

===CPC 664 / 6128 external===

A 34 pin IDC floppy cable as used in old PCs is perfect. If it even has a 5.25" edge connector you can use it directly.

For German Schneider/Amstrad 6128 models you will need a Centronics connector instead of the edge connector.

The 6128 Plus also needs a Centronics connector but with a slightly different pinout.

[[Image:Floppy_Cable.png|600px|centre]]

For full details look here: [[DIY:Floppy_Drives#Multi-Adaptor_Cable_for_External_Floppies_.2F_HxC_emulator]]

===CPC 664 / 6128 internal===

You can also use the GOTEK as a replacement for a broken 3" drive, just make sure to set the jumper on the GOTEK from S1 to S0.

As the GOTEK has a 34pin connector but the 3" drives have a 26pin connector you will also need a [[DIY:Floppy_Drives#Adaptor_Cable_for_Internal_Floppies_.2F_HxC_emulator|26 to 34 pin adapter]].

[[Image:Internal_HxC_Cable.png|600px|centre]]

PCB versions of this adapters that can be directly connected to a GOTEK are often also sold on e.g. Ebay.

You will also need a (3D printed) frame to properly mount the GOTEK in your CPC. You can find 3D models on the usual websites, e.g. Thingiverse. Remember to look for the right frame for your CPC model as the 664, 6128 and Plus all require different frames.

==HXC Manager==

Despite its name this software works with both FlashFloppy and HxC firmware.

Especially when using the 3 digit display the [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager] offers a great alternative to organise and mount DSK images. You can select 20 images and assign them to 20 slots which you navigate via the up/down buttons on the GOTEK.

[[File:Hxcmanager.jpg|thumbnail|none]]

==Related==
* [[HxC_Floppy_Emulator|HxC Floppy Emulator]]
* [[FlashFloppy]]
* [[ABBA_switch|ABBA switch - switch drive A to B and B to A]]
* [[Guide_on_how_to_connect_a_3.5#Primary_drive_setting_.28OPTIONAL.29|Forcing drive B to be Drive A]]

==Links==
* [https://github.com/keirf/FlashFloppy FlashFloppy on github]
* [https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]
* [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager]
* [https://hxc2001.com/ HxC Floppy Emulator Homepage]
* [http://www.cpcwiki.eu/forum/applications/cubeios-fat16fat32-rom-for-the-cpc's-with-xmass/ OS-Support]
* [https://youtu.be/QSLcgWLRztE Un Gotek sur CPC 664/6128 sans rien démonter] by [[Rodrik Studio]]
* [https://youtu.be/E3raN1yi54c L'ultime Gotek que j'ai dessiné pour CPC] by [[Rodrik Studio]]

[[Category:Peripherals]] [[Category:DIY]][[Category:DATA Storage]] [[Category:Emulator]]

Gotek

2025-07-28T19:56:15Z

Eto: reorganised content, removed dead links, added some details

[[File:Gotek standard.jpg|thumb|right|Standard Gotek drive]]
[[File:Custom Gotek drive.jpg|thumb|right|Custom Gotek drive by [[Rodrik Studio]]]]
[[File:Gotek external.jpg|thumb|External GOTEK for a Schneider CPC 6128 with Centronics cable, 3D printed top cover and splitter cable to connect to the original 5V from the monitor]]
[[File:Gotek-internal.jpg|thumb|Internal GOTEK with 3D printed frame and 26/34 pin adapter PCB]]

== About the GOTEK ==

GOTEK is a floppy drive emulator which can be directly attached to computers instead of a normal floppy drive. The drives are popular and cheap additions to many 80s and 90s computers including the Amstrad CPC.

The basic Gotek has a 7-segment 2 digit display which shows the currently selected disk image, a USB socket for a USB memory stick, and 2 buttons to choose previous and next image.

There are additional mods that can be added:
* speaker (to simulate the sound of the read/write head stepping as heard in a real drive)
* eject button
* rotary dial (turn the dial to select the disc image)
* LCD/OLED display (this shows more information including the name of the image)

The most recent version of the GOTEK (SFRKC30.AT4.35, based on the AT32F435 chip) usually already comes with OLED display and rotary encoder but is also more expensive than the basic models.

In addition to the GOTEK you also need
* 5V power (e.g. USB power supplies will work - or you can use the monitor's 5V power output with a Y-splitter cable)
* a 34pin ribbon cable to connect it to the CPC (e.g. an old PC floppy cable which has both 3.5" and 5.25" connectors)
* connector cable to update firmware of the GOTEK (depends on firmware type)

CPC Disk images are put onto a USB drive which is plugged into the front of the Gotek. On the GOTEK a disk image is selected (via buttons or rotary encoder) and then the GOTEK behaves almost exactly as if it is a normal drive connected to the CPC with the disk being inserted.

There is only a small difference compared to a real drive with older models: the disc motor signal is not connected internally to the Gotek. This means the ready signal will be active even if the disc motor is off. The new model SFRKC30.AT4.35 can pass the motor signal and reacts (delayed if wanted) to it for the ready signal. See below for FlashFloppy firmware.

The GOTEK can replace the internal drive of the 664/6128, e.g. if the internal drive is broken. Or it can be used as the external drive B. It can even work as a 3.5" or 5.25" drive for example with Parados or VDOS.

== Firmware Update ==

Before the GOTEK can be used with the Amstrad CPC it needs to be flashed with a custom firmware.

The process depends on the type and firmware and is documented on the homepages of the respective firmwares (see below).

===HxC Floppy Emulator firmware===

There is a version of the [https://hxc2001.com HxC Floppy Emulator] firmware that can be used on the Gotek. It must be purchased from the HxC website and can then be installed and used.

The firmware supports multiple computers and their disk image formats as well as the HFE v1 & v3 file formats.

Once the firmware has been installed into a Gotek it can be updated through the USB memory stick.

===FlashFloppy firmware===

[https://github.com/keirf/FlashFloppy FlashFloppy] is probably the most popular firmware for the GOTEK. It's well supported by the author Keir Fraser. Although completely free, Keir welcomes donations to [https://www.macmillan.org.uk/ Macmillan Cancer Support charity in the UK]. Please do a donation if FlashFloppy is of help to you.

The firmware supports multiple computers and their disk image formats.

Firmware installation is more easy than HxC firmware and only needs a USB-A to USB-A cable and the use of the original software of the microcontroller vendor to install the firmware. The process is very well documented on the FlashFloppy wiki.

Once installed further updates can be performed via the USB memory stick.

On the CPC, the following FF.cfg setting can be recommended:

<pre>
# Floppy-drive interface mode
interface = shugart

# Host platform
host = unspecified

# Pins 2 & 34 output (drive->host) manual configuration
pin02 = high
pin34 = rdy

# Rotational offset of disk after a track change
track-change = realtime

# Rotational offset of disk after draining a write to Flash
write-drain = realtime

# Index pulses suppressed when RDATA and WDATA inactive?
index-suppression = yes

# Milliseconds from head-step start to RDATA active.
head-settle-ms = 12

# Milliseconds delay from motor-on to drive ready.
motor-delay = 200
</pre>

The rest of the settings can be used to your liking as they depend on preference and not on hardware emulation.

== Models ==

The best Gotek to buy currently (12/22) is the Model SFRKC30.AT4.35.

This model features a Artery AT32F435 APU and as well a motor jumper. This completes the emulation as it simulates the motor spin-up time. They are usually offered with Rotary encoder and with OLED display.

On the CPC also the AT32F415 models can be a good alternative. They are cheaper and can be upgraded with rotary encoder and OLED display.

For full details on which models to use and which to avoid, see here:
[https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]

==Physical connection==

===CPC 464 / DDI===

You can directly connect the GOTEK to the DDI-1 cable connector however you would need to cut off the noses on the bottom of the cable - or you use a short IDC extension cable to avoid cutting of the noses. Please keep in mind that the DDI-1 is powered by the original FD-1 3" drive so you still need the FD-1 or need to power the DDI-1 via an alternative method.

===CPC 664 / 6128 external===

A 34 pin IDC floppy cable as used in old PCs is perfect. If it even has a 5.25" edge connector you can use it directly.

For German Schneider/Amstrad 6128 models you will need a Centronics connector instead of the edge connector.

The 6128 Plus also needs a Centronics connector but with a slightly different pinout.

[[Image:Floppy_Cable.png|600px|centre]]

For full details look here: [[DIY:Floppy_Drives#Multi-Adaptor_Cable_for_External_Floppies_.2F_HxC_emulator]]

===CPC 664 / 6128 internal===

You can also use the GOTEK as a replacement for a broken 3" drive, just make sure to set the jumper on the GOTEK from S1 to S0.

As the GOTEK has a 34pin connector but the 3" drives have a 26pin connector you will also need a [[DIY:Floppy_Drives#Adaptor_Cable_for_Internal_Floppies_.2F_HxC_emulator|26 to 34 pin adapter]].

[[Image:Internal_HxC_Cable.png|600px|centre]]

PCB versions of this adapters that can be directly connected to a GOTEK are often also sold on e.g. Ebay.

You will also need a (3D printed) frame to properly mount the GOTEK in your CPC. You can find 3D models on the usual websites, e.g. Thingiverse. Remember to look for the right frame for your CPC model as the 664, 6128 and Plus all require different frames.

==HXC Manager==

Despite its name this software works with both FlashFloppy and HxC firmware.

Especially when using the 3 digit display the [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager] offers a great alternative to organise and mount DSK images. You can select 20 images and assign them to 20 slots which you navigate via the up/down buttons on the GOTEK.

[[File:Hxcmanager.jpg|thumbnail|none]]

==Related==
* [[HxC_Floppy_Emulator|HxC Floppy Emulator]]
* [[FlashFloppy]]
* [[ABBA_switch|ABBA switch - switch drive A to B and B to A]]
* [[Guide_on_how_to_connect_a_3.5#Primary_drive_setting_.28OPTIONAL.29|Forcing drive B to be Drive A]]

==Links==
* [https://github.com/keirf/FlashFloppy FlashFloppy on github]
* [https://github.com/keirf/flashfloppy/wiki/Gotek-Models Gotek models on Flashfloppy wiki]
* [https://norecess464.weebly.com/hxc-manager-v4.html HxC Manager]
* [https://hxc2001.com/ HxC Floppy Emulator Homepage]
* [http://www.cpcwiki.eu/forum/applications/cubeios-fat16fat32-rom-for-the-cpc's-with-xmass/ OS-Support]
* [https://youtu.be/QSLcgWLRztE Un Gotek sur CPC 664/6128 sans rien démonter] by [[Rodrik Studio]]
* [https://youtu.be/E3raN1yi54c L'ultime Gotek que j'ai dessiné pour CPC] by [[Rodrik Studio]]

[[Category:Peripherals]] [[Category:DIY]][[Category:DATA Storage]] [[Category:Emulator]]

File:Gotek-internal.jpg

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File:Gotek external.jpg

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File:Hxcmanager.jpg

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CF2 Compact Floppy Disc

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[[Category:DATA Storage]]
The 3" discs for the [[Amstrad Disk Drive]] are called '''CF2''' (Compact Floppy Disc). CF2 discs were produced by [[AMSOFT]], MAXELL, [[Schneider]], Panasonic. In late eighties, cheaper Noname discs were also available (although these were rather unreliable).

Capacity is 180 Kbytes per side (the discs can be flipped to access the other side, giving a total of 360 Kbytes per disc).

Dimensions are 80x100x5mm. (more or less, depending the manufacturer)

(This article, [[:File:Amstrad Computer User8504 072.jpg]], also mentions something called Hitachi HFD-2 discs.)

In 1982 to 1983, there were some "microfloppy" formats competing to replace the 5¼″ floppy. However, in 1984 Apple choose the Sony 3½″ drives for their Macintosh computer. The Sony format became the de facto microfloppy standard but other formats, including the Hitachi 3″ and the 5¼″ still had plenty of life left in it. In 1987 IBM choose 3½″ in PS/2 PC architecture.

Alan Sugar, sign a deal with the manufacturers of three-inch disk drives to sell him units at a fixed percentage beneath the lowest-priced 3.5-inch drive, he got the cheapest option going for generations of computers. In 1985 a CPC computer appeared with 3" floppy. Towards the end, it was rumoured, Hitachi had to keep a factory going just for Amstrad — it lost money on each drive, but not as much as if it had broken the contract—. 3" format saw its finest hour in the PCW range of CP/M word processors which sold by the million: its passing leaves the world with a legacy of documents.

* CF2 Drive hardware makers:
Hitachi, Matsushita, Maxell, Teac, Amstrad

* Computers and Media Drives that use 3" CF2 standard:
- AMDECK (AMDISK) [1982] : external drive for TRS-80 , IBM PC , Atari 400/800 , Apple II
- YAMAHA MDR-1 [1983] : sequencer for professional organs. Pre-MIDI
- National MyBrain 3000 [1983] : computer
- Gavilan Laptop [1983]
- Tatung Einstein [1984]
- Oric Atmos external Disc Drive [1984]
- Sega SF-7000 Disc Drive (for Sega SC-3000 computer) [1984]
- Timex FDD / FDD-3000 drive ( for ZX Spectrum and Timex ) [1985]
- Amstrad / Schneider CPC [1985]
- Amstrad / Schneider PCW (8000 series) [1985]
- Sinclair Spectrum +3 [1987]
- Amstrad PCW 9000 series [1987]
- Amstrad CPC+ [1990]

PCW 8000 drive B or 9000 series drive A can handle the DD format (720k). Spectrum +3 bios can handle too if you add one of those PCW CF2-DD units (or 3,5" drive). Some CPC utils and ROMS would use PCW format (Knife) or PC DOS FAT12 720k format (BonnyDOS) (SymbOS).

== 3 Inch Discs Comments from John King ==

There is not much to be said about these 3 inch discs other than there is only one type but produced by a number of different manufacturers -- some good quality, many bad quality. I have identified what the years have shown me to be good quality, long lasting discs but beware do not judge the discs you might be offered by their paper labels as many cheap copies from suspect makers have appear in the market place, look at the discs themselves.

'''The Good'''

*[[Media:CF2DD Blue.jpg|Genuine Amsoft (Amstrad) 3" CF-2DD]]: This type of disc was originally supplied for the double head 720K drives at an enhanced price, then Amstrad admitted that these discs were no different to their other offering (see the first disc).

'''The Bad'''

*[[Media:BLANK5.JPG|Dixions Store supplied]]: Found to be unreliable and not to servive the rigours of time -- to be avoided at all costs!
*Maker Unknown - [[Media:BLANK6.JPG|Blank6]] & [[Media:Blank11.jpg|Blank11]]: These discs are found to be unreliable and do not last the rigours of time -- to be avoided at all costs.
*[[Media:Blank7.jpg|Copy (or poor quality) Amsoft]]: These discs normally come with an Amsoft label and I am lead to believe that they are cheap copies -- to be aviod at all costs. These discs tend to become corrupt and or fall to pieces.
*[[Media:BLANK8.JPG|Wiz Disc]]: Origin of manufacture is unknown but a test of six discs from the same batch revealled that most would not format to 720K but were fine at 180K -- to be avioded at all costs.
*[[Media:BLANK9.JPG|Diskxpress]]: Supplied by Diskxpress -- to be avioded at all costs.

'''And the should know better'''

*[[Media:Blank10.jpg|A look-a-like Maxell 3]]: Poor quality, jams in drive. Note no serial number on side 'B' unlike the Maxell disc it is trying to copy!

== 3 Inch Discs Comments from Jonathanen ==
When [https://web.archive.org/web/20110428132206/http://www.pcwking1.netfirms.com/ John King] has told me about using CF-2DD discs as standard CF-2 discs for the first time after I've purchased one of them (with the [[Media:CF2DD Blue.jpg|Blue label]]) back in Friday 2nd April 2004 as a souvenir as well purchasing other Amstrad CPC / PCW stuff from him (I was his regular customer, always calling him to reserve the items for me to collect after I've checked out his web site and then I travel 2 - 3 hrs by train, checking / testing out the merchandise at his house when I got there, collect, paid him by cash and then make another 2 - 3 hrs back on my way home, I didn't care how far he lives or how heavy the items that I'm carrying on my way back, as long I got the items that I always wanted), I thought he was making it up, until when I got home and decided to tested out his own theory, it turns out that he is right along and it works perfectly. Then, I've tried the reverse order using any standard CF-2 discs as CF-2DD discs, and it turns out that I'm right as well, as it works perfectly - check out my [https://web.archive.org/web/20130505073822/http://www.jonathanen.com/pages/Help/badsector.html "Re-using 3 Inch Floppy Discs with Bad Sectors"] link to see what I mean.

== 3 Inch Discs Comments from MacDeath ==

Those 3" floppies were known to be in chronic shortage... and for being far more expensive than other formats due to all the mechanical parts in them. In France they would sometimes cost about 4x or 5x times more than 5"1/4 or 3"1/2 (20-30 francs per piece instead of 5-10 francs for other formats, roughly)... They were supposed to have DD or HD version, but mostly only some PCW would use double sided disk drives with special format not quite compatible with simple sided disk drives.

That the PCW, a professional computer, would use those too in large number would create the shortage, as companies wouldn't mind bying bulk stocks of such floppies. The snoty CPC gaming user (or Speccy+3) would really have to think twice at what content he would put on those. Also the price of the disks would have impact on game devs and producers, as they would rarely aim at games using one whole or multiple floppies (6128 specific large games) because this could mean less profit, longer development time and only 6128 configs being able to launch games, the few amount of money spent on the floppies would quite render the game less profitable than small Tape oriented games (464 and 664 configs) that could be packed on one disk compilations. 16bit games would be sold at bigger price and would use far less expensive floppies anyway, so a game on 3-5 floppies would cost as much as a game on CPC on a full used disk in raw floppy material.

A 3" disk could be somewhat 360ko in total, basically the same as a quite basic 5"1/4DD, except that you would have to flip side on a CPC. quite rapidly, the 3"1/2 went for DD in 720ko or HD in 1.44mo at quite lesser price per disk (the disk drive could be quite expensive on the other hand) which was more suitable for 16bit computers (those would at minimum sport 512ko of RAM most of time passed the Atari STfm release / after 1986).

Some specific moded disk drives could perform special formats that were actually used as copy protection for some games, the most (only?) known exemple being Defender of the Crown on CPC. The french developper for the CPC version [[Brice Rive]] developped this specific method and went on to become UBIsoft copy protection specialist. He produced/coded [[Defender of the Crown]], but also E.X.I.T and copy protection for various [[Ubi Soft]] prods on CPC.

The story of this copy protection scheme was explained at CPCrulez french forum. The method consisted of moding some specific 3" floppy disk drives models so they could format the 3" floppies into something like 200-220ko per sides... Normal unmodified disk drives wouldn't be able to format disk the same way so the datas would need more floppies to be spread on and the copy, while still possible, would ask for many more disk switch and would render the game experience far less enjoyable. Cracked version of Defender of the Crown using 3 sides instead of only 2. Un-modified disk drives would still be able to read the specially formated floppies anyway (well, most of times I guess) and the extra sectors would not all be used actually.

More infos on this story there : http://www.cpcwiki.eu/forum/games/brice-rive-programmer-for-defender-of-the-crown-guest-star-at-cpcrulez/

The situation with this 3" format was a dead end. Amstrad went for cheap arrangement in production and adventageous contract so they wouldn't upgrade to DD/HD (720ko per disk) because the disk drives would be too expensive, hence no proper use in larger RAM configuration would be viable, both in PCW or CPC (or speccy+3). So those 8 bit computers couldn't really benefit from upgraded games comparable to 16bit machines in content, and so on.

Else it was a capable format, with somewhat robust floppies in elegant compact casings and quite fast disk access as well. CPC6128 was a pleasure to have. And by the way modern solution such as 3"1/2 disk drives or HxC floppy emulators are easily retro-fitable today.

The nostalgia value from those 3 inchers is always touching anyway : the solid recomforting view of a brand brand new elegantly grided Amsoft CF-2 floppy in this sweet classic "mode1 palette" of Black-Grey-White-BrightRed, often rendered in many demos in sweet pixel art, is so emblematic of the CPC era to most of us old CPC664-6128-externaldrive users. It is integral part of the Amstrad CPC culture.

== Pictures ==

[[File:CF2inside.jpeg|thumbnail|none|CF2 - what's inside]]

<gallery caption="Floppy Discs used by Amstrad CPC / PCW & +3 - The Good from John King">

<gallery>
File:Cf2 amsoft box and disc.jpg|Amsoft
File:CF2 Case.jpg|Amsoft CF2 in Jewel Case (Sealed)
File:Cf2 maxell pack.jpg|Maxell (pack)
File:Cf2 maxell.jpg|Maxell
File:BLANK2.JPG|Tatung - Picture from John King
File:CF2D.jpg|Maxell CF2-D for Amstrad PCW (Sealed)
File:CF2DD Blue.jpg|Amsoft CF2DD for Amstrad PCW
Image:AmstradAction046-50.jpg|AA Issue 46 - Page 50
</gallery>

<gallery caption="The Good or The bad ???">
<gallery>
File:CF2 Panasonic low.jpg|Panasonic
File:Cf2 schneider system disc.jpg|Schneider
File:Cf2 schneider box.jpg|Schneider
</gallery>

<gallery caption="The Bad - from John King">
<gallery>
File:CF2 Noname.jpg|Noname
File:BLANK5.JPG|Dixions - Picture from John King
File:BLANK6.JPG|Unknown - Picture from John King
File:Blank7.jpg|Copy (or poor quality) Amsoft 3" - Picture from John King
File:BLANK8.JPG|Wiz Disc - Picture from John King
File:BLANK9.JPG|Diskxpress - Picture from John King
File:Blank11.jpg|Unknown - Picture from John King

</gallery>

<gallery caption="And the should know better - from John King">
<gallery>
File:Blank10.jpg|A look-a-like Maxell 3" - Picture from John King
</gallery>

File:CF2inside.jpeg

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CPC iRAM

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[[File:Iram640.jpeg|thumbnail]]
[[File:Iram640 builtin.jpeg|thumbnail]]
[[File:Iram640ramtest.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 and CPC 464/664 (later hopefully also for the Plus/GX4000).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

== released ==

=== CPC iRAM/640 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

== currently in development ==

=== CPC iRAM/1088 ===

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Finished, will be released in late 2025

=== CPC iRAM/1024 ===

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, will be released in late 2025

=== CPC iRAM/1024s ===

* much smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype assembled, release unclear

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF150x)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF150x)

Status: just an idea

== abandoned ==

=== CPC iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

CPC iRAM

2025-07-09T22:41:11Z

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[[File:Iram640.jpeg|thumbnail]]
[[File:Iram640 builtin.jpeg|thumbnail]]
[[File:Iram640ramtest.jpeg|thumbnail]]

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 (later hopefully also for the 464 and 664).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

The first 512K of expansion RAM follow the [[Standard_Memory_Expansions#Standard_128K-512K_Expansions_.28dk.27tronics.2Fdobbertin-style.29|DK'Tronics addressing mode standard]], giving up to 576K of RAM to legacy software. More modern software that supports the [[Standard_Memory_Expansions#Extended_1M-4M_Expansions_.28RAM7.2FYarek-style.29|extended 1M-4M standard]] will be able to access all the provided RAM.

== released ==

=== CPC iRAM/640 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
* easy to assemble, all through-hole components
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Released - see https://github.com/etomuc/CPC6128_iRAM-640

== currently in development ==

=== CPC iRAM/1088 ===

* for CPC 6128 only
* 1024K expansion
* total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
* easy to assemble, but SRAMs are in SMD packaging (SOP32) due to size constraints in the CPC 6128
* perfectly fits into a CPC 6128, even with socketed ROM or RAM. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Finished, will be released in late 2025

=== CPC iRAM/1024 ===

* for CPC 464 and 664
* offers two sockets for SRAMs
* upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
* first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
* second SRAM: upgrade to 1024K (512K SRAM) or optionally also 640K (128K SRAM)
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted
* easy to assemble, all through-hole components

Status: Finished, will be released in late 2025

=== CPC iRAM/1024s ===

* much smaller than iRAM/1024, more similar in size to iRAM/640
* for CPC 464 and 664
* single 1MB SMD SRAM, upgrade to 1024K
* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported
* easy to assemble, mostly through-hole components but one SMD SRAM

Status: working prototype assembled, release unclear

== considered ==

=== PLUS iRAM/1024 ===

* 1Mb upgrade for Plus series
* less DIY friendly, probably needs more complex CPLDs (ATF150x)

Status: very early stage, still considering if it's feasible

=== GX iRAM/512 ===

* 512K upgrade for GX4000
* less DIY friendly, probably needs more complex CPLDs (ATF150x)

Status: just an idea

== abandoned ==

=== CPC iRAM/576 ===

* for CPC 6128 only
* 512K expansion
* total accessible RAM of 576K in a 6128 (following the DK'Tronics standard)
* easy to assemble, all through-hole components

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

=== CPC iRAM/512 ===

* for CPC 464/664
* 512K expansion
* total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
* or 576K without C3 support (512K_C3 / 576K selection per manual switch)
* easy to assemble, all through-hole components

Status: Abandoned as CPC iRAM/1024 will fit into all 464s/664s and is more flexible

[[Category:Hardware]] [[Category:Memory expansions]]

Connecting the CPC to a VGA monitor - CPC2VGA

2025-06-26T20:31:04Z

Eto:

Most VGA monitors won't support the CPCs signal directly and require an [[LCD_monitor_and_LCD_TV_Solution_(RGB)#Converter_options|active converter/scan doubler]] but some monitors are accepting a 15.6kHz signal like provided by the CPC.

In the late 80s and 90s there were a couple of CRT multisync monitors like the NEC Multisync series. For modern LCD monitors the support of 15.6kHz is rare but there are a couple of monitors that are known to work well: https://15khz.miraheze.org/wiki/Main_Page

If you own such a monitor you can easily connect the VGA monitor to the CPC. For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

Unfortunately, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. The NEC LCD 1970NX, which is often referred to as the perfect monitor for Amigas or Atari STs would be an example. In those cases, an adapter, that splits c-sync into h-sync and v-sync would be required.

Don't trust sellers who claim their adapter would be able to split the signals without the need of external power. While they don't lie per sé they "forget" to tell you that this requires that the VGA monitor provides power on pin 9 - which not all of them do (e.g. again the NEC 1970). In this case you will have a simple passive adapter that does not split the signal and still requires that the monitor accepts C-sync.

See section below on how to build an adapter which is externally powered and definitely splits the signal.

== Open Source CPC2VGA PCB ==

A simple circuit based on the LM1881 to split the Composite Sync signal into H- and V-Sync could be this:

{|
|-
| [[File:CPC2VGAschematics.png|thumbnail|none|CPC2VGA LM1881 schematics]] || [[File:Cpc2vga_plain.jpg|thumbnail|none|CPC2VGA - PCB fully built]]|| -
|}

* [[Media:Gerber CPC2VGA LM1881 240905.zip|Gerber Files]]

== Other solutions ==

If your VGA monitor does not support the 15.6kHz modes you will need an additional active adapter that adapts the frequency (scan doubler or scaler):

[[LCD monitor and LCD TV Solution (RGB)]]

[[Category:DIY| ]] [[Category:Hardware| ]]

LCD monitor and LCD TV Solution (RGB)

2025-06-03T09:54:16Z

Eto: /* vga4cpc */

Generally speaking, it's not too hard to connect the CPC to a modern LCD TV or monitor. Either the monitor already supports the CPC's signal directly, like TVs with SCART or RGB connector often do, or you can use one of the many converters that accept the RGB signal and convert it to a more modern signal, like VGA or HDMI.

If you are looking how to produce a Composite Sync signal, check [[LCD And Plasma TV Solution]].

== The Pitfalls of LCDs ==

One thing to keep in mind is, that there is yet no really perfect replacement for a CRT. There are mainly four issues, that will be different with an LCD.

=== Pitfall #1: power adapter ===

If you want to connect the CPC to anything but an Amstrad monitor you also need to provide a new power adapter, as the CPC does not have its own power adapter and relied on its original monitor. More information about this can be found in the article [[Power Supply for CPC and CPC plus]].

=== Pitfall #2: Screen lag ===

Once you connect the CPC to a modern monitor, you may experience a phenomenon, that some games just don't feel right. It's like you are too slow - or that the collision detection seems to be off. Of course, some games are just crappy in that regard, or you might just get old ;-). But it's at least as likely, that your set-up has a significant screen lag. Screen lag means, that there is a significant delay between the moment that your CPC sends a signal to the monitor and the moment that this signal is shown on screen. Old school monitors don't have a significant screen lag. The CPC updates its screen 50 times per second, and any update will be visible almost instantly on a CTM644, GT65 or any other old school monitor with a tube. the reason for this is, that these monitors work analogue. They display the signals they receive immediately. As soon as there are any digital devices involved, this changes. Digital devices have some kind of chips that take the analogue signal and transform them into digital signals. This transformation requires some time and depending on the logic that is built in, this time is almost neglectable - or can be so significant, that it harms your gaming experience. A lag of 1 or 2 frames often does not do any harm, but any lag above one or two frames can be recognisable, at least in fast paced games which you are familiar with. You will see bullets still quite a distance away from you, but in the computer, the bullets have already hit you. You simply can no longer react fast enough, so this might be even [https://www.youtube.com/watch?v=7VOsOuQ5mhM&t=12s THE most important aspect of your set-up].

(Note: Screen lag of course is not limited to games, but primarily there it can become a problem. If you want to measure the screen-lag of your set-up, there is a pretty easy way to do so, you just need your CPC, a mobile phone that can shoot videos at 120 or 240fps and a computer, to watch that video frame per frame. See: [[Testing your Screen-Lag with a CPC]])

=== Pitfall #3: CRTC tricks ===

Not all demos and games will work if you are using an LCD. Games and demos that push the limit of the CPC, especially with CRTC tricks, might not work with a modern LCD. Relentless is a famous example, that (at the point of writing this article) will only work on real CRT monitors (or emulators of course). Although this sounds like a huge drawback, on a daily basis, it's not as bad. With the right set-up, except for a few exceptions like Relentless, all games and even most demos will work perfectly or in a way, that you don't experience problems.

=== Pitfall #4: pixel mask ===

(colour) CRTs have a pixel mask to produce red, green and blue from a single electronic beam. On a CRT there is no such thing as a sharp pixel. When you compare the same picture on a CRT and a LCD, you will see, that the picture on the CRT is much more blurry - but also smoother. It's personal preference if you like one more or the other. Or you don't bother. But some people would never replace their beloved CRT for an LCD, just because of the pixel mask.

{|
|-
| [[File:ModernLCD AsphaltCRT.JPG|thumbnail|none|Pixel mask of a CRT]] || [[File:ModernLCD AsphaltLCD.JPG|thumbnail|none|The same game on a LCD]]
|}

== How to connect to a modern LCD ==

The CPC monitor connector offers 3 lines for the colours red, green and blue, and one line for a composite sync (csync) signal, that combines horizontal and vertical sync. The horizontal frequency is 15.6Khz and the vertical frequency is 50Hz. In short: If your monitor supports RGB and these frequency values, you can use your monitor with a simple, passive adapter. If not, you need an active converter.

=== Options with passive adapters ===

==== LCD TV sets (SCART) ====

Many LCD TV sets offer a SCART connector, which often accepts the CPC signal directly. All you need is a [[TV SCART cable|CPC-to-Scart cable]] that you can either build yourself, or buy on Ebay for not too much money. Especially if you want a distinct monitor for your retro corner anyway, this can be a pretty nice and cheap solution. Used 15" camping TV sets have just the right size to feel comfortable and can be bought for a few bucks on Ebay or your local classifieds.

Your only enemy here is: screen lag. Some of the LCD TVs perform almost like CRTs, others seem to include a SCART2HDMI converter, and they have a bad lag (see below).

==== LCD computer monitors (VGA) ====

Some VGA LCD monitors are know to support the 15.6kHz frequency. These often can be connected with a simple DIN to VGA adapter. Screen lag of LCD monitors is usually very good and close to non-existing or half a frame max.

For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.

{|
|-
| [[File:CPCVGAconnectorPinouts.png|thumbnail|none|CPC and Plus to VGA - pinouts]] || [[File:ModernLCD CPC2VGA1.JPG|thumbnail|none|CPC to VGA (female) adapter]] || [[File:ModernLCD CPC2VGA2.JPG|thumbnail|none|CPC to VGA cable]]
|}

A known example for a perfectly working monitor is the BENQ 702A. More examples can be found on the internet (see links below), but be aware, although the [https://pinoutguide.com/Video/VGAVesaDdc_pinout.shtml VGA standard should accept Csync on pin 13], some monitors expect separate v-sync and h-sync signals. In those cases, [[Connecting the CPC to a VGA monitor - CPC2VGA|an adapter, that splits c-sync into h-sync and v-sync (CPC2VGA)]] would be required.

=== Converter options ===

There are plenty of active converters to connect retro computers and consoles to modern TVs and monitors. Their biggest difference is performance and price. And if you are not willing to do a bit of soldering, you probably will end up with either spending a lot of money - or getting a bad solution.

==== SCART to HDMI converters ====

SCART to HDMI converters are the cheapest and most simple solution. Make sure they (really) support RGB and not only composite video, like the cheapest SCART to HDMI converters usually do. RGB SCART converters start at around 30€ (2022). They will usually work and you will probably first think, that this is perfect, but they can add a hefty lag to your screen, some add up to 120ms (or 6 frames).

[[File:ModernLCD Scart2HDMI.JPG|thumbnail|none|Typical Scart2HDMI box]]

This Youtube video explains in detail why you should [https://youtu.be/7VOsOuQ5mhM?t=587 avoid Scart to HDMI converters for retro gaming].

It's fine if you only want to do a bit of BASIC programming or play adventures, but it could do some harm to fast action games.

==== Scan converters ====

===== Framemeister / OSSC =====

There are quite a few scan converters specifically built to connect many (all) retro computers and consoles to modern screens. The most famous ones are probably Framemeister and [https://junkerhq.net/xrgb/index.php?title=OSSC Open Source Screen Converter (OSSC)]. They are very flexible, have lots of options, zero or very low lag - and are really or quite expensive. Actually the only disadvantage they have is, that they are expensive. If you have a big retro collection, with several machines and consoles that you want to hook up to your LCD, then one of those might be the right choice. If not, there are cheaper, still great alternatives.

===== GBS8200 (VGA) / HD-VC9900 (HDMI) =====

These converters have originally been made to convert signals of arcade boards to modern LCD monitors via VGA (GBS8200) or HDMI (VC9900).

[[File:ModernLCD GBS8200GBSControl.JPG|thumbnail|none|GBS 8200 with GBS Control mod]]

They do support the signal of the CPC but without any further modification, the conversion quality is limited. It adds up to 2 frames of lag, which might be just acceptable, but many famous games and demos won't work due to synching problems. All this improves a lot, once you add the GBS control mod to it. That's basically adding a microcontroller to the original board, that takes over control and adds features and flexibility that are [https://www.youtube.com/watch?v=fmfR0XI5czI&t=879s close to the Framemeister and OSSC]. Also the lag shrinks down to [https://www.youtube.com/watch?v=fmfR0XI5czI&t=783s less than a frame], at least if your monitor does not add much lag on top.

See [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200] and [https://github.com/ramapcsx2/gbs-control/issues/165 VC9900]

Especially the GBS8200 is easily available and incredibly cheap and if you know how to solder, the GBS Control mod is easy to do. And that's of course also the downside: you need to solder - and probably also 3D print a case for the GBS.

Update: Some sellers have adopted the GBS Control firmware and offer full products based on the GBS 8200 chipsets and the GBS Control mod. The price is a bit more than building one yourself - but still A LOT cheaper than any other (good) scaler solution. On the positive side it also already includes a case and HDMI output. Offers can be found e.g. on Amazon or AliExpress. Search for "GBS Control". No test has been docuemted so far with a CPC, so there's still a risk that the hardware behaves differently from a self-built GBS mod.

===== RGB2HDMI =====

[https://www.youtube.com/watch?v=2CnsQBGAuos The new star on the horizon.] An open source project, that combines a Raspberry Pi with some custom logic, to convert signals from home computers and home consoles to HDMI. For almost every computer there is a more or less different version of the board. You can build the RGB2HDMI yourself or buy a finished version, e.g. on sellmyretro.com . It's features are even beyond those of the OSSC and Framemeister. Its total price is somewhere between the GBS and the OSSC, depending on where you buy it. And its tiny. Its biggest disadvantage is, that you need a different version of the board per console or home computer (well - some computers share a similar signal, so e.g. for the BBC you can also use the CPC version, but e.g. an Amiga or an Amstrad Plus each need another converter version). Screen lag has not been measured yet for it, but it seems to be very low.

===== vga4cpc =====

This DIY project by forum user gregg is based on the Raspberry Pico and (as of November 2024) the only solution that supports most (all?) CRTC tricks. Even games like Relentless that do not render properly on any of the other scan doublers are perfectly playable and absolutely smooth. Hardware and software are publicly available and the scan doubler can be built for less than €30 (€10-€30, depending on shipping costs for the parts). Assembly should be doable for anyone with average soldering skills.

Github project: https://github.com/grzegorz-gr/vga4cpc

Forum thread: https://www.cpcwiki.eu/forum/amstrad-cpc-hardware/vga-through-rpi-pico-how-many-colors-possible-on-border/

The only downside would be that it only supports the Amstrad CPC, so if you own other computers (or even a Amstrad Plus or GX4000), you still need another solution.

{|
|-
| [[File:Vga4cpc.jpg|thumbnail]] || [[File:Picovgacase.jpg|thumbnail]]
|}

''Eto''

== Links ==

CPC Wiki

* [[TV_SCART_cable|How to - Scart cables]]
* [[LCD And Plasma TV Solution]] (Composite Video)
* [[Power Supply for CPC and CPC plus]]

External

* [https://github.com/ramapcsx2/gbs-control GBS Control for GBS8200]
* [https://www.youtube.com/watch?v=7VOsOuQ5mhM Screen Lag - explanation and comparison video]
* [http://15khz.wikidot.com List of 15kHz compatible monitors]
* https://15khz.net similar list

[[Category:Hardware]] [[Category:Peripherals]] [[Category:DIY]] [[Category:Graphic]]