Siemens SINUMERIK 840D sl Programming Manual page 97

The system variable $P_SUBPAR returns
• TRUE, if the transfer parameter was programmed
• FALSE, if no value was set as transfer parameter.
If an impermissible parameter number was specified, parts program processing is aborted
with alarm output.
Call main program as subroutine
A main program can also be called as a subroutine. The end of program M2 or M30 set in
the main program is evaluated as M17 in this case (end of program with return to the calling
program).
You program the call specifying the program name.
Example:
N10 MPF739 or
N20 Shaft3
Note
A subroutine can also be started as a main program.
Job planning
Programming Manual, 03/2006 Edition, 6FC5398-2BP10-1BA0
Subroutines, Macros
2.4 Call subroutines (L or EXTERN)
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