Process Data And Diagnostic Status - WAGO 750-306 Technical Description

114 • DeviceNet

Process data and Diagnostic Status

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
Strobe Function
Change of State
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.
Slaves are cyclically polled by the master.
All slaves are polled by the master by means of
a command.
Messages are transmitted either cyclically by
the master or the slave, or in the event of a state
change.
WAGO-I/O-SYSTEM 750
DeviceNet