Siemens SINUMERIK 840D sl Programming Manual page 345

Meaning
M:
<address extension>:
<value>:
Predefined M functions
Certain important M functions for program execution are supplied as standard with the control:
M function
M0*
M1*
M2*
M3
M4
M5
M6
M17*
M19
M30*
M40
M41
M42
M43
M44
M45
M70
Note
Extended address notation cannot be used for the functions marked with *.
The functions M0, M1, M2, M17 and M30 are always triggered after the traversing movement.
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
Address for the programming of the M functions.
The extended address notation applies for some M functions (e.g.
specification of the spindle number for spindle functions).
Assignment is made to a certain machine function through the value
assignment (M function number).
Type:
Range of values:
Meaning
Programmed stop
Optional stop
End of program, main program (as M30)
Spindle clockwise
Spindle counter-clockwise
Spindle stop
Tool change (default setting)
End of subprogram
Spindle positioning
End of program, main program (as M2)
Automatic gear change
Gear stage 1
Gear stage 2
Gear stage 3
Gear stage 4
Gear stage 5
Spindle is switched to axis mode
2.13 Auxiliary function outputs
INT
0 ... 2147483647 (max. INT value)
Fundamentals
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