Manual VIPA System 300S
Chapter 3 Deployment
HB140E - IM - RE_353-1DP01 - Rev. 14/47
3-5
DP-V0
provides the basic functionality of DP, including cycle data
exchange as well as station diagnostic, module diagnostic and channel-
related diagnostic.
Data is transferred cyclically between the DP master and the DP slave by
means of transmit and receive buffers.
DP master
Input
Output
DP slave with I/O-Modules
I/O Modules
Communications
Processor
buffer receive
Bus
buffer send
Bus cycle
DP cycle
PI
PIQ
PROFIBUS DP
PII: process image of the inputs
PIQ: process image of the outputs
A bus cycle saves all the input data from the modules in the PII and all the
output data from the PIQ in the output modules. When the data has been
saved the PII is transferred into the ”send buffer” and the contents of the
”receive buffer” is transferred into PIQ.
During a PROFIBUS cycle the master addresses all its slaves according to
the sequence defined in the data exchange. The data exchange reads and
writes data from/into the memory areas assigned to the PROFIBUS.
The contents of the PROFIBUS input area is entered into the ”receive
buffer” and the data in the ”send buffer” is transferred into the PROFIBUS
output area.
The exchange of data between DP master and DP slave is completed
cyclically and it is independent from the bus cycle.
Function
cyclic data
communication
(DP-V0)
Bus cycle
DP cycle
