This project takes in mic/line level audio from the 3.5mm jack and digitizes it using a Raspberry Pi Pico 2.
The audio is sent through the serial interface in a modified 48kHz 16-bit 2-channel PCM format. The audio is sent in packets of 32768 samples each, with a 0xFFFF stop character at the end to ensure left/right channel alignment.
The JetKVM reads its serial interface from /dev/ttyS3 and sends the raw byte packets though the network to a client PC running a python script (test_piping.py) that decodes the packets into a standard PCM audio stream.
Since the JetKVM doesn't ship with scp by default, we can use ssh and pipe the binary manually: cat build/audio-client-c | ssh root@jetKVM "cat > /root/audio-client-c"
On the client: ssh root@jetkvm "/root/audio-client-c" | ffplay -fflags nobuffer -f s16le -ch_layout stereo -ar 48k -.
If you're going to fab this board design you should know the tip and sleeve contacts on the 3.5mm jack footprint are backwards.
