Technical data

☞
If DP bytes need to be transferred together (e.g. analog
values/counted values with word or double word length), the
FREE update mode must under no circumstances be
selected. With this mode, there is no guarantee that the DP
bytes which belong together are actually transferred in one
frame.
Essential features of the FREE mode:
➣
Minimum cycle load (corresponds to the cycle load that would occur
simply by plugging in the corresponding input/output modules..
➣
Minimum load on the CP, since no HDB calls are required for
communication.
➣
Simple programming of data exchange (single handling block call; HDB
SYNCHRON for the CP during start-up of the PLC).
Distributed I/Os (DP) B89060/02
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