HEIDENHAIN ITNC 530 User Manual page 519

10.4 Separate Program as
Subprogram
Operating sequence
1 The TNC executes the part program up to the block in which
another program is called with CALL PGM.
2 Then the other program is run from beginning to end.
3 The TNC then resumes the first (calling) part program with the
block behind the program call.
Programming notes
No labels are needed to call any program as a subprogram.
The called program must not contain the miscellaneous functions
M02 or M30.
The called program must not contain a CALL PGM call into the calling
program, otherwise an infinite loop will result.
HEIDENHAIN iTNC 530
0 BEGIN PGM A 0 BEGIN PGM B
CALL PGM B
END PGM A
END PGM B
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