System Variables For Synchronized Actions; Reading And Writing - Siemens SINUMERIK 828D Function Manual

2.3

System variables for synchronized actions

The system variables of the NCK are listed in the "System Variables" Parameter Manual with
their respective properties. System variables that can be read or written in synchronized
actions, are marked with an "X" in the corresponding line (Read or Write) of the "SA"
(synchronized action) column.
Note
System variables used in synchronized actions are implicitly read and written synchronous to
the main run.
References
A comprehensive description of the system variables listed in this function manual can be
found in:
● System Variables Parameter Manual
2.3.1

Reading and writing

The reading and writing of variables is performed in the main run in synchronized actions
with a few exceptions. Exceptions are:
● User-defined variables: LUD, GUD
● Machine data: $M...
● Setting data: $S...
● R parameters: R<number> or R[<index>]
These variables are already read and written during the preprocessing.
Synchronized actions
Function Manual, 07/2012, 6FC5397-5BP40-3BA0
2.3 System variables for synchronized actions
Detailed description
17