Technical data

The DP update times are in no way connected to the communications
taking place on the L2 bus.
The data exchange with the L2-DP service between the CP and the L2-DP
slaves is constant (cyclic according to the DP polling list entry) regardless of
the call cycle of the handling blocks SEND 210 and RECEIVE 211. To start
the DP polling list processing in the CYCLE-SYNCHRONIZED mode, at
least one HDB checkpoint (SEND 210/RECEIVE 211) must be called.
Using the status word bits 8 - 11 of the HDB checkpoint, diagnostic
information can be analyzed.
SEND-HDB
A-NR 210
RECEIVE-HDB
A-NR 211
Read inputs
Write outputs
I/O area
of the CP 5430 TF/CP 5431 FMS
Processing the
DP polling list
PLC cycle
L2 bus
t
User
:
:
Fig. 11.11 Function of the CYCLE-SYNCHRONIZED Mode
B8976060/02 Distributed I/Os (DP)
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