Siemens SINUMERIK 840Di sl Programming Manual page 231

Note
This means that each of these instructions cancels all other previously programmed frame
instructions.
The last called settable zero offset G54 to G599 is used as the reference.
Additive instructions
ATRANS, AROT, ASCALE and AMIRROR are additive instructions. The currently set zero
point or the last workpiece zero to be programmed with frame instructions is used as the
reference. The above instructions are added to existing frames.
Note
Additive statements are frequently used in subroutines. The basic functions defined in the
main program are not lost after the end of the subroutine if the subroutine has been
programmed with the SAVE attribute.
References:
/PGA/Programming Manual Advanced; "Subroutines, Macros"
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
Frames
6.2 Frame instructions
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