Siemens SIMATIC CP 340 - Page 108

Communication using function blocks
6.3 Using the function blocks for connecting to a communications processor
PtP coupling and configuration of CP 340
108 Manual, 04/2011, A5E00369892-03
Time Sequence Chart for P_SEND (FB 3)
The figure below illustrates the behavior of the DONE and ERROR parameters, depending
on how the REQ and R inputs are wired.
5(4
5
'21(
(5525
6HQGLQJUHTXHVW 7HUPLQDWLRQZLWKRXWHUURU 7UDQVIHU5(6(7 7UDQVIHU5(6(7 7HUPLQDWLRQZLWKRXWHUURU 5HTXHVWLV QRWH[HFXWHG 6HQGLQJLV WXUQHGRII 7HUPLQDWLRQZLWKHUURU
VWQWK6(1'SDUW
Figure 6-1 Time Sequence Chart for P_SEND (FB 3)
Note
The REQ input is edge-triggered. A positive edge at the REQ input is sufficient. The result of
the logic operation must not be at "1" at any point during transfer.