I2S protocol issue (MSB inverted)

[StreakingJerry]

CircuitPython version

Adafruit CircuitPython 8.1.0 on 2023-05-22; ESP32-S3-Box-Lite with ESP32S3

Code/REPL

import time
import array
import audiocore
import board
import audiobusio

audio = audiobusio.I2SOut(board.I2S_SCLK, board.I2S_LRCK, board.I2S_CODEC_DSDIN)
d = array.array("H", [0])
d[0] = 0b1111111111111111
print(d)
w = audiocore.RawSample(d, sample_rate=8000)
audio.play(w, loop=True)
while True:
  time.sleep(1)

Behavior

This is what I got from oscilloscope: The yellow line is the LRCK and the green line is DSDIN.

If I change d[0] to 0b0000000000000000, This is the outcome:

Obviously the MSB is inverted.

Also, I find that the left_justified parameter does not work. It seems that the default value is False. However, there is no different on oscilloscope whether set it to True or False.

Description

No response

Additional information

No response

[dhalbert]

Triage notes:

• Input array is unsigned, but check whether I2S is expecting signed data.
• if left_justified doesn't work, either fix or throw an error.