```
o<m12> sub

    ; Move tool carousel CW Parameter P number of steps
    ; Without parameter one step CW.
    ; Parameter #5170 is used to track the current tool pocket (persistently)
    (print, o<M12> P#<p>)
    M112 P#<p>

    O100 if [EXISTS[#<p>]]
        #<Steps_to_move> = #<p>
    O100 else
        #<Steps_to_move>=1
    O100 endif

    O110 if [#5171 NE 1]
        (print, atc not homed, homing)
        M13
    O110 endif

    M64 P3 ; Move atc motor FWD

    O120 do
        M66 P4 L1 Q3 ; wait for falling edge on rotation index
        O130 if [#5399 LT 0]
            (abort, failed to get rotation index)
            M65 P3 ; Stop atc motor
        O130 endif
        #5170 = [[[#5170-2] MOD 12]+1]    ;Pocket is no.1-12
        #<Steps_to_move> = [#<Steps_to_move>-1]
    O120 while [#<Steps_to_move> GT 0]

    M65 P3 ; Stop motor
    #<_my_current_pocket> = #5170

o<m12> endsub [1]

M2