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DMC question

DMC question
by on (#49610)
What happens when you play a DMC sample that does left the delta-counter with a different number than the initial one ?

If I understand things well, $4011 initially contains $00 at reset. When playing a sample it will either increase or decrease by two, or keep at $00 or at $7f (altough technically there is no write to $4011, the effect is similar). After playing the first sample, the counter is not compulary containing $00 again. This would imply that the counter would go upwards on each sample plays before reaching some maimum value. Am I correct ? I'm having trouble to test such behavior with emus, they seem to autoatically reset the value written to $4011 at the beginig of the sample. I don't see such a reset mentionned in any doc nor on the wiki. Does it happen ?

If the reset doesn't happen I'd say the "safe" way would be to end all samples with 65 '0' bits to reset the counter to 0 in all cases to avoid sounding distorder (well it will sound very distorded anyway).
Re: DMC question
by on (#49614)
Bregalad wrote:
If I understand things well, $4011 initially contains $00 at reset. When playing a sample it will either increase or decrease by two, or keep at $00 or at $7f (altough technically there is no write to $4011, the effect is similar). After playing the first sample, the counter is not compulary containing $00 again. This would imply that the counter would go upwards on each sample plays before reaching some maimum value. Am I correct ?

Yes. Eventually, the counter will saturate at $7E at some point during the sample.

Quote:
I'm having trouble to test such behavior with emus, they seem to autoatically reset the value written to $4011 at the beginig of the sample.

Accurate ones don't. Or maybe you're just not hearing the effect of the saturation.

by on (#49617)
Thanks you for clearing up the situation.

by on (#49623)
Even if a sample saturates, it won't stay saturated very long.