I2S Loopback Test

i2s_loopback.py

import board
import pio_i2s

SIZE = 1024

# Bridge GP2 and GP3
i2s = pio_i2s.I2S(
    bit_clock=board.GP0,
    word_select=board.GP1,
    data_out=board.GP2,
    data_in=board.GP3,
    buffer_size=SIZE,
)

buffer_out = [i for i in range(SIZE)]
i2s.write(buffer_out, loop=True) # Loop fills double-buffered output
buffer_in = i2s.read()

error = 0
for i in range(SIZE):
    if buffer_out[i] != buffer_in[i]:
        error += 1

print(error)