Siemens SINUMERIK 840D sl Function Manual page 619

The M function is selected with the index of machine data MD10715
$MC_M_NO_FCT_CYCLE[<Index>] in which the M function to be replaced has been
parameterized:
MD10718 $MC_M_NO_FCT_CYCLE_PAR = <Index>
Note
For an M function replacement with transfer of information via system variable, the address
extension and function value of the M function must be programmed as constant values.
Permissible programming:
● M<function value>
● M=<function value>
● M[<address extension>]=<function value>
Illegal programming:
● M=<variable1>
● M[<variable2>]=<variable1>
Programming
Rules for replacing M functions:
● The replacement subprogram is called at the block end
● Within the replacement subprogram, no M functions are replaced
● In an ASUB, the M function is also replaced if the ASUB was started within the replacement
subprogram.
M functions that cannot be replaced
The following M functions trigger system functions as pre-defined auxiliary functions and must
not be replaced by a subprogram:
● M0 ... M5
● M17, M30,
● M19
● M40 ... M45
● M98, M99 (only for MD18800 $MN_MM_EXTERN_LANGUAGE ≠ 0)
User-specific M functions parameterized via machine data must also not be replaced by a
subprogram as they also trigger system functions.
Machine data
MD10714 $MN_M_NO_FCT_EOP
MD10804 $MN_EXTERN_CHAN_M_NO_SET_INT
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
K1: Mode group, channel, program operation, reset response
9.17 Replacing functions by subprograms
Meaning
M function for spindle active after RE‐
SET
M function for ASUB activation (exter‐
nal mode)
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