Digging into SPDIF channels status bits

 

Digging into SPDIF channels status bits

Some years ago, it required was quite expensive equipment to debug SPDIF connections and do low-level analysis on these. With the DAC+ DSP or the Beocreate 4CA it is now easy to access these information. All you need is the DSP board, DSPToolkit and a small script.

#/bin/bash
for i in 0xf61 0xf62 0xf63 0xf4; do
 res=""
 for j in 0 1 2 3 4 5 6 7 8 9 a b; do
  reg=`dsptoolkit read-reg $i$j`
  res="$res $reg"
 done
 echo $i: $res
done

What does this do? It simple reads the SPDIF status bit registers directly from the DSP and displays them. It will display 4 lines:

  • status bits left
  • status bits right
  • user data bits left
  • user data bits right

What can you do with this? One use case for it is debugging/reverse-engineering propietary protocols. You can see an example here.
You can see an example here.