7   6   5   4   3   2   1   0   7   6   5   4   3   2   1   0
   +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
00 | Fixed prefix 'C' (43h)        | 03h                           |
   +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+