[[File:Iram640.jpeg|thumbnail]]
[[File:Iram640 builtin.jpeg|thumbnail]]
[[File:Iram640ramtest.jpeg|thumbnail]]
CPC [[File:Iram640.jpeg|thumbnail|iRAM is a series of open source, DIY friendly, internal RAM expansions /640 for the CPC 6128 (later hopefully also ]][[File:Iram1024.jpg|thumbnail|iRAM/1024 for the CPC 464 and /664).]]
The CPC iRAM is the first [[Standard_Memory_Expansions|standard]] compatible, internal plug & play RAM expansion sits 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 requires 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.
== released ==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/640Iram640 builtin.jpeg|iRAM/640 built-inIram640ramtest.jpeg|RAM Test</gallery>
* for CPC 6128 only
* 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.
StatusRepository: Released - see https://github.com/etomuc/CPC6128_iRAM-640
== currently in development ==''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 iRAM/1024 ===
* for === CPC 4646128 - iRAM/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 640K (128K SRAM) or 1024K (512K SRAM)* [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM banking] supported if both SRAMs are fitted* easy to assemble, all through-hole components1088 ===
Status: in active development
== paused / abandoned ==<gallery> === CPC 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 some SRAMs are in SMD components 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.
StatusRepository: Prototype successfully tested. No final PCB yet. Might be resumed if there's demandhttps://github.com/etomuc/CPC6128_iRAM-1088
=== CPC 464/664 - iRAM/576 1024 ===
* <gallery>iRAM1024.jpg|iRAM/1024 for CPC 6128 only464/664iRAM1024symbos.jpg|SymbOS on CPC 464</gallery> * 512K expansionfor CPC 464 and 664* total accessible upgrade to 1024K including [http://norecess.cpcscene.net/advancedmemoryusage.html C3 RAM of 576K in a banking] support for 6128 compatibility* alternatively without C3 support 576K or 1088K (following the DK'Tronics standardone or two SRAMs fitted)
* easy to assemble, all through-hole components
StatusRepository: https: 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 modegithub. * or 576K without C3 support (512K_C3 com/etomuc/ 576K selection per manual switch)* easy to assemble, all throughCPC464-hole componentsiRAM1024
Status: currently on halt as CPC iRAM/1024 will fit into all 464s and 664s and is more flexible
[[Category:Hardware]] [[Category:Memory expansions]] [[Category:DIY| ]]