Siemens SINUMERIK 840D sl Programming Manual page 346

Fundamentals
2.13 Auxiliary function outputs
M functions defined by the machine manufacturer
All free M function numbers can be used by the machine manufacturer, e.g. for switching
functions to control the clamping devices or for the activation/deactivation of further machine
functions.
Note
The functions assigned to the free M function numbers are machine-specific. A certain M
function can therefore have a different functionality on another machine.
Refer to the machine manufacturer's specifications for the M functions available on a machine
and their functions.
Examples
Example 1: Maximum number of M functions in the block
Program code
N10 S...
N20 X... M3
N180 M789 M1767 M100 M102
M376
Example 2: M function as high-speed output
Program code
N10 H=QU(735)
N10 G1 F300 X10 Y20 G64
N20 X8 Y90 M=QU(7)
M7 has been programmed as fast output so that the continuous-path mode (G64) is not
interrupted.
Note
Only use this function in special cases as, for example, the chronological alignment is changed
in combination with other function outputs.
Further information about the predefined M commands
Programmed stop: M0
The machining is stopped in the NC block with M0. You can now remove chips, remeasure, etc.
346
Comment
; M function in the block with axis movement,
; spindle accelerates prior to X axis movement.
; Maximum of five M functions in the block.
Comment
; Fast output for H735.
; Fast output for M7.
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
NC programming