PROFIBUS DP communication
BK3xx0
52
Version: 4.3.0
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
Fig. 36: Output data in the Bus Coupler
Input data in the Bus Coupler
Fig. 37: Input data in the Bus Coupler
