HEIDENHAIN iTNC 530 (340 49x-06) ISO programming - Manual (Page 246)

246 Programming: Subprograms and Program Section Repeats
8.2 Subpr
ogr
a
ms
Calling a subprogram
U To call a subprogram, press the LBL CALL key.
U Call subprogram /repeat : Enter the label number of
the subprogram you wish to call. If you want to use a
label name, press the LBL NAME soft key to switch
to text entry If you want to enter the number of a
string parameter as target address: Press the QS soft
key; the TNC will then jump to the label name that is
specified in the string parameter defined.
G98 L 0 is not permitted (Label 0 is only used to mark the
end of a subprogram).