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• DeviceNet
Process data and Diagnostic Status
WAGO-I/O-SYSTEM 750
DeviceNet
5.4.2 I/O Messaging Connections
The transfer or exchange of process data between the scanner and the I/O de-
vice is made via a „Polled I/O Connection“, „Change of State/Cyclic“ or „Bit
Strobe“.
Polled I/O Connection
Slaves are cyclically polled by the master.
Strobe Function
All slaves are polled by the master by means of
a command.
Change of State
Messages are transmitted either cyclically by
the master or the slave, or in the event of a state
change.
5.5 Process data and Diagnostic Status
The data is transmitted between master and slave in the form of objects, a dif-
ferentiation being made between input and output objects. The object archi-
tecture is defined by assembly objects which serve to group attributes of dif-
fering application objects. I/O data of different objects can, for this reason, be
grouped to form a data block and transmitted by a message connection.
5.5.1 Process Image
The process image is differentiated according to input and output process im-
ages. The assembly object makes a statically configured process image avail-
able in the instances 1 ... 9.
The desired process image can be selected by setting the Produced Connection
Path and the Consumed Connection Path of the individual I/O connections
(Poll, Bit Strobe, Change of State or Change of Value).
The architecture of the individual instances of the assembly object is described
in the following.
