Using the ADC to record stereo signals

[escher]

I was reading the API docs for i2s_set_adc_mode:

Code: Select all

esp_err_t i2s_set_adc_mode(adc_unit_t adc_unit, adc1_channel_t adc_channel)

The only acceptable adc_unit_t is ADC_UNIT_1. (ADC_UNIT_BOTH is "not supported yet").

Does this mean that the ESP32 ADCs are incapable of recording stereo signals or is there a way? I note the ESP-ADF examples outsource the audio work to the ES8388.

[escher]

So, I assume not possible then? The STM32 ADC1 and ADC2 can be synchronized in dual mode at orders of magnitude of Msps with hardware triggering; whereas the ESP32 can't do any of that? It's disappointing.

[ESP_Sprite]

It's... complicated. The long and short of it is that WiFi needs to use ADC2 to measure some things with relation to the analog bits of the hardware. We haven't found an elegant way to make that mesh with simultaneous sampling of ADC1 and ADC2 yet.