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Re: Rasters and TimerC SNDH
Posted by: spkr Dec,18.2019-23:29 

In short. Instruments (sounds outputted by the music driver) can be non-timer dependent and timer-depending effects.

Non-timer depending instruments change the YM2149 chips settings whenever the musicdriver (mym) is called (in your example case 56hz, driven by timer c interrupts).

Timer depending instruments change on a different `occurence/timing' than whenever the music driver is called. To achieve this, the music driver, when called, programs the MFP, using timers (timer a, timer b and timer d in MYM case); such that programmed interrupt code is executed. Depending on the instrument (SID, Digisound etc), the timer interrupt timers are scheduled and the userdefined vectors (sound code) are defined.

So, there is the possible cause of your issue(s):
You use timer-based music, while having the wish to use timers for your code as well. In mym, the channel in which the intrument is used, determines which timer is used for timer effect (channel 1; a, channel 2; b, channel 3; d). So it could also very well be that you are overwriting timers that are also used by mym music driver; and weird stuff can happen.

I cant magically debug your code remotely, but if you send me the binary, I can at least explain what makes it crash in your case.

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Topic Posted by  Date 
Rasters and TimerC SNDH Stalvik Dec,17.2019-12:45
  Re: Rasters and TimerC SNDH spkr Dec,18.2019-23:29
    Re: Rasters and TimerC SNDH uko Dec,19.2019-00:21
      Re: Rasters and TimerC SNDH Stalvik Dec,19.2019-15:30
        Re: Rasters and TimerC SNDH spkr Dec,19.2019-15:31
  Re: Rasters and TimerC SNDH gwEm/PHF Dec,19.2019-16:43
    Re: Rasters and TimerC SNDH Stalvik Dec,19.2019-17:24

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