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Dual Chip Support

Technical discussion about the VGM format, and all the software you need to handle VGM files.

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  • snakemeat Offline
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Dual Chip Support

Post by snakemeat »

Per the v1.70 spec:

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All chips of the YM-family use 0xAn. n is the last digit of the main command.
e.g. 0x52 (1st chip) -> 0xA2 (2nd chip).
Is this only for commands 0x51 - 0x5B? Are 0x5C - 0x5F included? Are 0xD0-0xD1 included?
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  • ValleyBell Offline
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Post by ValleyBell »

Right... I'm a bit inaccurate there.
It's for commands 0x51-0x5F.
0xD0/0xD1 are done in a way similar to about all other chips: by ORing the first parameter byte with 0x80.

Data blocks that go to the second chip have their size ORed with (1<<31).
  • snakemeat Offline
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Post by snakemeat »

Thanks!
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