Possible to use NoDac output like esp8266audio

[MartinNohr]

Is there any way to output PDM with no DAC as in your other audio library?

[earlephilhower]

Yes, but it needs to be ported, of course. It should be a pretty easy port, why not give it a try?

I thought the Espressif chips had real PDM which basically did the same thing for you, though. That's what the PDM module here ises. On the Raspberry Pi chips, they all have real HW PWM so we just use that. Hence, no ported DeltaSigma DAC...

[MartinNohr]

I guess I don't know the answer to that about the esp32. I'm not using the S3 newer version, I'm using whatever is on the Lilygo TTGO T-Display. I better go do some reading...

[earlephilhower]

I guess I don't know the answer to that about the esp32.

You and me both, brother. 😆 The Espressif catalog is insane and all under ESP32, from a single core RISC-V to something closer to a Raspberry Pi 2W SBC-on-a-chip.

That said, if you can instantiate the PDM output device here the SDK is saying that your specific model does have that hardware. It's ifdef'd using what was the latest Espressif SDK defines.

OTW, I'd pull in the deltasigma function from ESP8266Audio or make your own and go the new output object way. If you have it take an AudioOutputBase pointer and wrap the block conversion, then it would seamlessly work on the Pico and any ESP32s (although on the Pico there's HW PWM which is just as good and on many ESP32 variants the PDM gives something almost equivalent....the PDM HW has a different DC offset AFAICT).