5 ms·
The RP2040's DMA engine can update the PWM registers without burning a CPU. Use two DMA channels and you can play a sequence of samples, all with the DMA hardwa
by trebligdivad 3y ago
The RP2040's DMA engine can update the PWM registers without burning a CPU.
Use two DMA channels and you can play a sequence of samples, all with the DMA hardware after the CPU sets it up.
(I don't know if you can do that from micropython)
I did this in a little speaking ohmeter hack I did a couple of years ago:
https://gitlab.com/penguin42/ohmy https://gitlab.com/penguin42/ohmy
- rasz 3y agoDMA chaining is simply magic. First stumbled across it in a Microchip PIC. Does anyone know when it was invented? All I could find was this 2003 IBM patent https://patents.google.com/patent/US20030229733A1/en https://patents.google.com/patent/US20030229733A1/en but I have a feeling Microchip had it earlier?