Machine And Setting Data ($$M, $$S) - Siemens SINUMERIK 840D sl Function Manual

3.3.7

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] < $$SA_OSCILL_REVERSE_POS2[Z] DO $AA_OVR[X] = 0
Writing during the main run
The following requirements must be satisfied for writing during the main run:
● The access authorization at the time of writing must be sufficient for writing.
● The machine or setting data must have the property "Effective immediately".
Program code
; The switching position of the SW cam $SN_SW_CAM_ ... must,
; depending on the current setpoint of the X axis in WCS $AA_IW[X],
; only be written during the main run
ID=2 WHEN $AA_IW[X] > 10 DO $$SN_SW_CAM_PLUS_POS_TAB_1[0] = 20
A complete overview of the properties of the machine and setting data can be found in:
Synchronized actions
Function Manual, 08/2018, 6FC5397-5BP40-6BA2
3.3 System variables for synchronized actions
$$SN_SW_CAM_MINUS_POS_TAB_1[0]=20
Detailed description
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