Siemens SIMATIC CP 340 User Manual page 117

Time Sequence Chart for FB 4 P_PRINT
The figure below illustrates the behavior of the DONE and ERROR parameters, depending
on how the REQ and R inputs are wired.
Figure 6-4
Note
The REQ input is edge-triggered. A positive edge at the REQ input is sufficient. It does not
have to have a signal state of "1" during the entire transmission operation.
PtP coupling and configuration of CP 340
Manual, 04/2011, A5E00369892-03
6.4 Using function blocks for the output of message texts to a printer
Time Sequence Chart for FB 4 P_PRINT
Communication using function blocks
117