Problems with YM sound effects on real hardware (works in emulators)

All aspects of programming on the Commander X16.
DragWx
Posts: 394
Joined: Tue Mar 07, 2023 9:07 pm

Re: Problems with YM sound effects on real hardware (works in emulators)

Post by DragWx »

kliepatsch wrote: Sun Apr 27, 2025 2:58 pm This is what is working reliably for me (16 cycles if I count similarly to you). With one less NOP, I got occasional FM glitches on real HW. Not 100% certain but I think glitches occurred mostly during patch changes.

sta YM_reg nop ; 2 cycles each nop nop nop nop nop sty YM_data ; 4 cycles
Yeah, I need to do more testing on mine once my FM support is mature enough, to see if I get issues with only 10 cycles delay. By the way, I have a YM2151, is yours also a 2151 or is it a 2164? I don't know if the delays are different between the two chips.
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kliepatsch
Posts: 256
Joined: Thu Oct 08, 2020 9:54 pm

Re: Problems with YM sound effects on real hardware (works in emulators)

Post by kliepatsch »

I have a YM2164.
DragWx
Posts: 394
Joined: Tue Mar 07, 2023 9:07 pm

Re: Problems with YM sound effects on real hardware (works in emulators)

Post by DragWx »

I got a chance to test more thoroughly; 3-channel music with patch changes, note volume calculations, etc, and there weren't any issues so far. If I release something, and the FM music doesn't work properly on the 2164, then it wouldn't be a problem to add more delay after address write if it turns out the '64 needs a different delay from the '51.
doslogo
Posts: 33
Joined: Fri Dec 20, 2024 4:26 pm

Re: Problems with YM sound effects on real hardware (works in emulators)

Post by doslogo »

DragWx wrote: Wed Apr 30, 2025 7:30 pm I got a chance to test more thoroughly; 3-channel music with patch changes, note volume calculations, etc, and there weren't any issues so far. If I release something, and the FM music doesn't work properly on the 2164, then it wouldn't be a problem to add more delay after address write if it turns out the '64 needs a different delay from the '51.
Sounds splendid to me!
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