PWM - Revision history

Arnoldemu at 12:29, 11 March 2018

2018-03-11T12:29:12Z

Freemac at 22:18, 18 September 2017

2017-09-18T22:18:29Z

Freemac at 22:16, 18 September 2017

2017-09-18T22:16:02Z

Deprecated: The each() function is deprecated. This message will be suppressed on further calls in /mnt/cpcwiki-httpdocs/includes/diff/DairikiDiff.php on line 434

Freemac at 14:31, 5 March 2017

2017-03-05T14:31:40Z

Freemac at 14:29, 5 March 2017

2017-03-05T14:29:22Z

Freemac at 14:28, 5 March 2017

2017-03-05T14:28:55Z

Freemac at 14:27, 5 March 2017

2017-03-05T14:27:05Z

Freemac at 14:25, 5 March 2017

2017-03-05T14:25:42Z

Freemac at 14:24, 5 March 2017

2017-03-05T14:24:44Z

Freemac at 14:22, 5 March 2017

2017-03-05T14:22:32Z

← Older revision		Revision as of 12:29, 11 March 2018
Line 97:		Line 97:
	PWM_out <= PWM_Accumulator(8);		PWM_out <= PWM_Accumulator(8);
	end PWM_arch;		end PWM_arch;
		+
		+	[[Category:Hardware]]

@@ Line 56: / Line 56: @@
   entity PWM is
     port (
-     clk : in std_logic; -- 50MHz : higher than dog and cat frequency
+     clk : in std_logic; -- 50MHz : higher than dog and cat frequency, a multiple of clk_ref
      clk_ref : in std_logic; -- 1MHz : same one as sound chip clk
      PWM_in : in std_logic_vector (7 downto 0) := "00000000";

@@ Line 12: / Line 12: @@
   entity PWM is
     port (
-     clk : in std_logic;
+     clk : in std_logic; -- 1MHz : same one as sound chip clk
      PWM_in : in std_logic_vector (7 downto 0) := "00000000";
      PWM_out : out std_logic
@@ Line 56: / Line 56: @@
   entity PWM is
     port (
-     clk : in std_logic;
+     clk : in std_logic; -- 50MHz : higher than dog and cat frequency
-     clk_ref : in std_logic;
+     clk_ref : in std_logic; -- 1MHz : same one as sound chip clk
      PWM_in : in std_logic_vector (7 downto 0) := "00000000";
      PWM_out : out std_logic

@@ Line 29: / Line 29: @@
   end PWM_arch;
-Ok, let's go further, let's target 2.5v using only 0v and 5v, with a stupid slow clock, you result in a sequence like this : 05050505050505v. It has a bad border effect : it a noise ! 2.5v normaly doesn't produce sound by here, but using this simple PWM it does.<br />
+Ok, let's go further, let's target 2.5v using only 0v and 5v, with a stupid slow clock, you result in a sequence like this : 05050505050505v. It has a bad border effect : it's a noise ! 2.5v normaly doesn't produce sound by here, but using this simple PWM it does.<br />
 This problem is solved here : this is an original homemade PWM component enabling Arkanoid not producing noises instead of silents, don't ask me how I solved it two years ago but it does :

@@ Line 1: / Line 1: @@
 Pulse Width Modulation, is a DAC (Digital Analog Convertor) using only numerical components (outputting only 0v or 5v values)<br />
-Using an entry clock, you output several signals 0v or 5v in order to result an average fix value between 0v and 5v, for sample 2.3v. Changing like it the speed of a small electric motor (speeding it up or slowing it down) as you want but using at its input only two values : 0v or 5v.<br />
+Using an entry clock, you output several signals 0v or 5v in order to result an average fix value between 0v and 5v, for sample 2.3v. Changing like it the speed of a small electric motor (speeding it up or slowing it down) as you want but using at its inputs only two values : 0v or 5v.<br />
 Using a quicker clock, you can generate analog signal, like sound music.

@@ Line 39: / Line 39: @@
   --  {@  {@{@{@{@  {@  CoreAmstrad is implementation of FPGAmstrad on MiST-board
   --  {@{@        {@{@   Contact : renaudhelias@gmail.com
-  --  {@{@{@{@{@{@{@{@   @see https://github.com/mist-devel/mist-board/wiki
+  --  {@{@{@{@{@{@{@{@   @see http://github.com/mist-devel/mist-board/wiki
   --    {@{@{@{@{@{@     @see FPGAmstrad at CPCWiki
   --