AnsweredAssumed Answered

Which DMA-Channels for simple Audio (Mono ADC/DAC)?

Question asked by bil.til on Feb 27, 2016
Latest reply on Feb 28, 2016 by bil.til
Hi,
could somebody recommend me perhaps, which DMA configuration to use for simple Audio (STM32L4, Analog micro connected to ADC, simple speaker amp connected to DAC - I want do record to WAV files and play back from WAV files on some SD card).

(I do NOT want to use a digital interface as SAI, I2S ... I need to accomplish the audio things with as few pins as possible, and I hope that for ADC/DAC I need only 1 line for the micro ADC and 1 line for the speaker DAC).

I am still planning the PCB layout configuration, not yet inside the software:
For the Micro side: Is it better to use a DMA channel of an ADC, or is it better to use some Timer DMA channel (which would be much more flexible of course, as there are very many Timer DMA channels).
For the Speaker side: Is it better to use a DMA cannel of an DAC, or is ok to use some Timer DMA channel?

I hope that maybe I can use the same timer, e.g. TIM17, and then configure two DMA channels for this timer (e. g. Channel 1 and 7), and then perform recording and playing with one timer (only if recording + playing should be necessary, but usually anyway I would either record or play...).

Outcomes