I/O Terminal /
MANUAL CONFIGURATION
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Special Signals and Interfaces
The Bus Coupler supports Bus Terminals with other interfaces such as RS232, RS485,
incremental encoder and others. These signals can be considered similarly to the analog
signals named above. For some special signals the bit width of 16 is not sufficient. The Bus
Coupler can support any byte width. It is necessary to consider how data consistency is
ensured when accessing these values. This means that update commands must not be
issued nor must the Bus Coupler be placed into the free running mode between the
accesses.
Default Assignment of the Inputs and Outputs to the Process Image
Once it has been switched on, the Bus Coupler finds out how many Bus Terminals are
inserted, and creates an assignment list. The analog and digital channels, divided into inputs
and outputs, are assembled into separate parts of this list. The assignment starts on the left
next to the Bus Coupler. The software in the Bus Coupler collects consecutively the individual
entries for each of the channels in order to create the assignment list counting from left to
right. Four groups are distinguished in the assignment:
Group
Functional type of the channel
Assignment
1
analog outputs
byte-wise
2 digital
outputs
bit-wise
3
analog inputs
byte-wise
4 digital
inputs
bit-wise
All complex Bus Terminals are represented by analog inputs or outputs.
Overview of the Distribution of the Process Image Within the Bus Coupler
Output data in the Bus Coupler
