/*
           (1*)          (2*)
       6 5 4 3 2 1    3  2  1  0
    00 0 0 0 0 0 0   00 00 00 00   00000000  000     000   00
    -- ---------     ------------  --------  ----    ----  -----
       side_states   device_state  progress  device  side  state
                                       ^       ^      ^      ^
                                       |       |      |      |
               calibration progress in %       |      |      |
        current device number during calibration      |      |
            current side (if exists) during calibration      |
                                     current calibration state
    see froly-protocol.h:
    (1*) CALIBRATION_SIDE_<NAME> 1 bit per side
    (2*) CALIBRATION_DEVICE_<NAME> 2 bits per state
    progress, device, side, state are uint8_t
*/