I took a look at the abandoned implementation above and don't think it would work well with Arduino-Pico's audio management. So I spent an hour this morning and hacked up an I2S input slave mode implementation, see https://github.com/earlephilhower/ardui ... /pull/3244 .
Note that because the PIO only gets one input base pin, you need to ensure the wiring is 3 consecutive pins, DIN, BCLK, LRCLK. DIN always has to be the 1st pin of the sequence because "in pins, #" always shifts in starting with the 1st input.
I tested against another Pico running the SimpleTone test and got the expected +/-500 square wave as input.
Note that because the PIO only gets one input base pin, you need to ensure the wiring is 3 consecutive pins, DIN, BCLK, LRCLK. DIN always has to be the 1st pin of the sequence because "in pins, #" always shifts in starting with the 1st input.
I tested against another Pico running the SimpleTone test and got the expected +/-500 square wave as input.
Statistics: Posted by earlephilhower — Tue Nov 18, 2025 5:59 pm