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7.2
M-functions
M-functions define machine instructions. They are processed in the CNC and, moreover,
transmitted to the PLC. They are evaluated in the PLC and trigger the programmed function
in the PLC in cooperation with the CNC.
M-functions have no parameters. The coordination between the PLC and the CNCV is made
by means of system variables, that are describes in /8/.
The following examples show some important M-functions:
Tabelle 30:
Table 30:
Important M-functions
M
Meaning in the CNC
14
Start of contour, activates the summing-up of the path length in the parameter field P551.
When using M14 in an online program (program with reloading of program components),
the execution of the program is blocked until the end of the contour is in the storage (M15/
M16/M21)
15
End of contour, deactivates the summing-up of the path length in P551 (start of idle travel)
30
End of program
E, L
Selection of the feeding speed via the number of revolutions (E) and the step size
(L) F=E*L.
Parameter
Meaning
Table 29:
Parameters for G02 and G03
