I started looking into the USB Protocol, but I'm at the wrong end of a learning curve on this one.
Here's what I have:
These 2 sequences start the focuser talking:
3b 03 22 12 fe cb --connect -->3b 07 12 22 fe 07 0f 20 30 61
3b 03 22 12 40 89 --?????? -->3b 04 12 22 40 00 88

Focuser continues to send this while you are connected.
keep alive
3b 03 22 12 01 c8 -->receive 3b 06 12 22 01 ignore last 4 bytes, appears to be counting (3b 06 12 22 01 00 83 59 e9 ) or timestamp

3b 04 22 12 25 09 9a move in 3
3b 04 22 12 25 00 a3 move in

3b 04 22 12 24 09 9b move out
3b 04 22 12 25 00 a3

3b 06 22 12 02 00 83 a4 9d move to 33700 = 0x83a4

byte1 always 3b
byte2 message length
byte3 always 22
byte4 always 12
byte5 command

final byte is a checksum, CheckSum8 2s Complement, on 2nd byte - (last byte-1)

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