For ID51 the Sony reponds to a 13-bit device code considered to consist of a 5-bit device and 8-bit sub-device code expressed as 23.133. All regular Sony protocols use 7-bit commands and that means 128 commands for each device code. So I can generate commands 0 through 127 in Pronto hex using John Fines MakeHex for device=23.133 and you can test them out.

If you recall I looked at the DVR-7000 and I created the commands that I believe would be the discrete power commands if they had them and it didn't work. The only other way would be to test out all possibilities of two consecutive, different 32-bit commands that would be 64 total bits. That would be 2 to the 64th power possibilities.

Let me know if you want all the commands for the Sony.

-Jon