Any alternative to arduino's tone() function?

[zamonary1]

I want to make a project for ch32v003j4m6 that is going to play short PCM samples from its (limited) flash.
One way would be to bit-bang everything and hand this task to CPU, but I think there might be a way to attach a PWM channel to a timer and dynamically change its frequency and modulation.
Is there any way to do so?

[eeucalyptus]

Yes, I actually implemented a delta-sigma DAC for the '003 which I unfortunately didn't finish yet. My project was a minecraft creeper that blinks, hisses and "explodes" on button press.

If you want PCM audio, you can just set the samples as duty cycles for the PWM. The audio quality is going to be poor though, due to very noisy and hard to filter output. Generating the sound with the PWM is also fine, but you will be very limited in your creative decisions. Having a proper delta sigma modulation instead is going to give you hd sound and with a proper driver stage (power mosfets and an LC filter) you have your class d amp integrated directly.

hmu if you are on the cnlohr discord and interested in collaborating on this.

As reference, there's eg.

• https://github.com/cpldcpu/ModPlayRISCV
• https://github.com/BogdanTheGeek/ch32fun-audio

hope that helps :)