HEIDENHAIN TNC 620 (340 56x-03) ISO programming - Manual (Page 326)

326 Programming: Multiple Axis Machining
1
1
.4 Miscellaneous F
unctions f
or Rotary Ax
es
Selecting tilting axes: M138
Standard behavior
The TNC performs M128 and TCPM, and tilts the working plane, only
in those axes for which the machine tool builder has set the
appropriate machine parameters.
Behavior with M138
The TNC performs the above functions only in those tilting axes that
you have defined using M138.
Effect
M138 becomes effective at the start of block.
You can reset M138 by reprogramming it without entering any axes.
Example NC blocks
Perform the above-mentioned functions only in the tilting axis C:
N50 G00 Z+100 R0 M138 C *