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452 bytes added ,  14:25, 3 January 2015
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| 0xC
 
| 0xC
 
| 1
 
| 1
| Value
+
| Duty value (3 bits), see below
 
|-
 
|-
 
| 0x10
 
| 0x10
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|}
 
|}
   −
This is similar to cmd2, except this updates channel CNT bit1-bit0.
+
This command updates bit0 through (at least) bit2 of the channel's CNT register. These bits control the duty of a PSG square wave:
 +
 
 +
  0  12.5% "_______-_______-_______-"
 +
  1  25.0% "______--______--______--"
 +
  2  37.5% "_____---_____---_____---"
 +
  3  50.0% "____----____----____----"
 +
  4  62.5% "___-----___-----___-----"
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  5  75.0% "__------__------__------"
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  6  87.5% "_-------_-------_-------"
 +
  7  0.0% "________________________"
    
==Command 0x8==
 
==Command 0x8==
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| Sample rate clamped to the following range(by the user process): 0x42-0xFFFF. This is the same value used with Cmd 0x8, except clamped.
 
| Sample rate clamped to the following range(by the user process): 0x42-0xFFFF. This is the same value used with Cmd 0x8, except clamped.
 
|}
 
|}
 +
 +
Bits 0 through 5 are written as zero to the CNT register.
    
PSG: Channels 8 through 13 play a square tone that is 16 samples long. Channels 14 and 15 play noise. It is currently unknown how to set the duty of the square tones.
 
PSG: Channels 8 through 13 play a square tone that is 16 samples long. Channels 14 and 15 play noise. It is currently unknown how to set the duty of the square tones.

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