ABB S800 I/O Manual page 63

Section 4 Operation
2 and 5
Input and output values are updated
as fast as possible (depends on the
configuration). Signal conditioning is
also performed in this loop.
1 and 6
Input and output values are updated
"as fast as possible" (depends on the
S800 I/O module configuration).
Figure 18. Dynamic Data Exchange for PROFIBUS-DP/DPV1 in Runtime
The transportation of dynamic data between PROFIBUS-DP/DPV1 and the
ModuleBus is the main task for the FCI. The FCI has a dedicated memory area
where it sends the output values and reads the input values. The CPU in the FCI
performs the rest of the data transportation. It reads output values from the memory
and writes to the I/O Modules via the ModuleBus and vice versa.
3BSE020926-600
Dynamic Data Exchange
PROFIBUS Master (Class 1)
PROFIBUS
3.
4.
Fieldbus Communication
Interface (FCI)
Communication Memory
2.
5.
Functional Description
The PROFIBUS Master uses Data Exchang
request towards the FCI according to it's
scheduling scheme.
3 and 4
Data exchange with PROFIBUS-D
cyclic and consists of both writing
data from Master to FCI as well as
read from FCI to Master.
Input Module Output Module
Chan x
Values Values
1.
Process
Chan x
6.
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