HEIDENHAIN ITNC 530 - CONVERSATIONAL PROGRAMMING User Manual page 276

8.1 Labeling Subprograms and
Program Section Repeats
Subprograms and program section repeats enable you to program a
machining sequence once and then run it as often as desired.
Labels
The beginnings of subprograms and program section repeats are
marked in a part program by labels (LBL).
A LABEL is identified by a number between 1 and 999 or by a name
you define. Each LABEL number or LABEL name can be set only once
in the program with the LABEL SET. The number of label names you
can enter is only limited by the internal memory.
If a label name or number is set more than once, the TNC
sends an error message at the end of the LBL block. With
very long programs, you can limit the number of blocks to
be checked for repeated labels with MP7229.
Label 0 (LBL 0) is used exclusively to mark the end of a subprogram
and can therefore be used as often as desired.
276 Programming: Subprograms and Program Section Repeats