08/2008
3 Setting up functions
3.
3
Fault service
s
© Siemens AG 2008 All Rights Reserved
ePS Network Services, Function Manual (FH) - Release 08/2008
3-137
Description of the "Feedback to PLC" function
The function that provides feedback related to any given trigger event to the PLC
writes individual pieces of information to the PLC.
4 bytes are available in DB 10, DBB118, DBB119, DBB120 and DBB121 of the
SINUMERIK PLC for this purpose (this function is only available for SINUMERIK).
It is possible to select the way in which the data bytes are divided and formatted so
that this is the same for all feedback messages.
Fig. 3-41: Feedback messages to PLC
The feedback messages can be written to the PLC once for each control monitor.
Variables are displayed for this purpose; these appear as they have been config-
ured for the feedback messages, and with the names they have been given for the
messages. ePS Network Services only allows variables to be written in a config-
ured format.
It is possible to switch directly to the settings menu from here in order to adjust and
configure the variable format.
Note
Variable format settings can only be changed if none of the control monitors are
writing to the variable in the set format. Any feedback messages being written
must be removed before the format can be changed.
The contents of the absolute variable addresses are completely overwritten with
the information specified here. Individual bits are written selectively. Individual bits
can only be written as bytes. For this purpose it is possible to determine whether a
bit is to be set to 1 or 0, or is to remain without an entry as it currently appears in
the PLC.
ePS Network Services ensures that in each case, a variable configured as an ab-
solute address is always written as a complete entity (i.e. not byte-by-byte or bit-by-
bit).