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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% "___-----___-----___-----"
+ 5 75.0% "__------__------__------"
+ 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.