Machine And Setting Data ($$M, $$S) - Siemens SINUMERIK 828D Function Manual

2.3.7

Machine and setting data ($$M, $$S)

Reading and writing MD and SD
When machine and setting data is used in synchronized actions, a distinction must be made
as to whether this remains unchanged during the execution of the synchronized action, or is
changed through parallel processes.
Data that remains unchanged can already be read or written by the NC during
preprocessing.
Data that is changed can only be read or written by the NC during the main run.
Data access during preprocessing
Machine and setting data that can already be read and written in synchronized actions
during preprocessing, is programmed with the same identifiers as in the part program: $M ...
or $S ...
Program code
; The reversal position of the Z axis $SA_OSCILL_REVERSE_POS2[Z]
; remains unchanged over the entire machining period
ID=2 WHENEVER $AA_IM[z]<$SA_OSCILL_REVERSE_POS2[Z]–6 DO $AA_OVR[X]=0
Data access during the main run
An additional "$" is added as prefix for machine and setting data that may only be read or
written in synchronized actions during the main run: $$M... or $$S...
Program code
; The reversal position of the Z axis $SA_OSCILL_REVERSE_POS2[Z]
; can be changed by operator input at any time
ID=1 WHENEVER $AA_IM[z] < $$SA_OSCILL_REVERSE_POS2[Z] DO $AA_OVR[X] = 0
Synchronized actions
Function Manual, 07/2012, 6FC5397-5BP40-3BA0
2.3 System variables for synchronized actions
Detailed description
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