how do I send audio though sigma-delta and can it use DMA?
Posted: Wed Oct 20, 2021 8:54 pm
I am starting to design an audio output from the esp32-s2. The sigma-delta 1-bit output looks like a good solution. However, I'm confused about how you send audio samples to the sigma-delta output gpio. The esp docs seem to only talk about config.
There is one param called duty-cycle which I think is like a pwm output in that it changes the average output level across the pulses. But do I have to call this function for each sample in my own loop? Is there a way to use dma? I'm concerned about the cpu load doing it from time interrupts. Also a big concern is the stabilty of the sample timings. Jitter is not a good-thing.
Any help would be appreciated.
There is one param called duty-cycle which I think is like a pwm output in that it changes the average output level across the pulses. But do I have to call this function for each sample in my own loop? Is there a way to use dma? I'm concerned about the cpu load doing it from time interrupts. Also a big concern is the stabilty of the sample timings. Jitter is not a good-thing.
Any help would be appreciated.