In my casual research some years ago, I didn’t find any method to interface the internal ADC/DAC to an other device, interfaces seem to be just? boot source options.
How to Program Guide for a similar board.
This Arduino I2C interface lib consolidates the generated code into a simpler header,
a little samd21 board like a Pi Pico or tiny Adafruit QY Py with 2Mb flash pads, might make a sufficient UI connector in a little box project, hopefully can eliminate need fror programming board…
An Arduino Shield interface
That board looks like the ideal minimal guts for a pedal, Can you tell if your copy has the ADAU1401 or the ADAU1701 (turns out to not really matter)
(Just added El Rockero project reference above…)
Spec sheets were looking identical, found the FAQ Answer:
(1401 high higher temp range)
What is the difference between the ADAU1701, ADAU1702, and ADAU1401?
Functionally, these parts are identical. The differences are in the sizes of the program and data RAMs. The ADAU1701 has 1024 instructions/cycle in the program RAM and 2k words of data memory, while the ADAU1702 has 512 instructions/cycle and 0.5k words of data memory. The ADAU1401 has the same specs as the ADAU1701, but is qualified over the automotive temperature range.
I suspect there are a lot more of these embedded in amplifiers doing simple crossover filtering than in guitar pedals.