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Last updated on Oct-18-2019 Download

NES Saw Wave

NES Saw Wave
by on (#96165)
Is timing available and precise enough to use the triangle channel in such a fashion as to play the rising part of the triangle wave, and then immediately cut and re-start the wave? Or is the "position" of the wave not predictable enough to allow for this?

I remember seeing a Saw wave demo some time ago and I have been curious how this was achieved.

by on (#96167)
Saw wave demo was using the DMC channel, some pcm value writes, and interrupts.

But as for using Triangle wave as a saw wave, you'd need to reset the phase half-way through the wave. And with the exact timing necessary to accomplish this, you're better off just using RAW PCM instead.
Edit: rainwarrior says it doesn't work...

Also, have you seen SuperNSF? Multichannel mod player for the NES!

by on (#96168)
The triangle cannot be reset.

Blargg did it with DPCM and IRQ.

by on (#96282)
I'm pretty sure that Memblers's Squeedo synth cart utilizes a saw wave on the triangle channel...

Also this thread may be more useful in "NES Music".