Querying System Variables - Siemens SINUMERIK 840D sl Function Manual

H2: Auxiliary function outputs to PLC
8.15 Information options
Display update
The display is organized in such a way that the collected auxiliary functions are always
displayed first, before those that were managed by the PLC and before those that were
managed by the NC. A collected auxiliary function is marked as collected until it has been
output from the NCK to the PLC. PLC-managed auxiliary functions are retained until they are
displaced by another auxiliary function. In the case of a reset, only the collected auxiliary
functions and the NC-managed auxiliary functions are deleted.
8.15.2

Querying system variables

Function
Auxiliary functions can be queried on a group-specific basis via system variables in the part
program and via synchronized actions:
$AC_AUXFU_... [<n>] = <value>
system variables
$AC_AUXFU_PREDEF_INDEX[<n>]
$AC_AUXFU_TYPE[<n>]
$AC_AUXFU_EXT[<n>]
or M function specific:
$AC_AUXFU_M_EXT[<n>]
440
Meaning
<value>: Index of the last auxiliary function collected for
an auxiliary function group (search) or the last
predefined auxiliary function to be output
Type INT
:
If no auxiliary function has been output yet for the
specified group or if the auxiliary function is a
user-defined auxiliary function, the variable sup‐
plies the value "-1".
<n>: Group index (0 to 63)
Note:
A predefined auxiliary function can be uniquely identified via
this variable.
<value>: Type of the last auxiliary function collected for an
auxiliary function group (search) or the last aux‐
iliary function to be output
Type CHAR
:
<n>: Group index (0 to 63)
<value>: Address extension of the last auxiliary function
collected for an auxiliary function group (search)
or the last auxiliary function to be output
Type INT
:
<n>: Group index (0 to 63)
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions