Configuring Hardware and Communication Connections STEP 7.pdf

8 Synchronous Operation of Multiple CPUs
(Multicomputing)
8.1 What You Should Know About Multicomputing
What is Multicomputing Operation?
Example
Multicomputing means the simultaneous operation of more than one CPU with
multicomputing capability (up to a maximum of four) in one central rack of the
S7-400.
The participating CPUs automatically change their operating modes synchronously,
meaning the CPUs start up together and go into STOP mode together. The user
program for each CPU executes independently of the user programs in the other
CPUs. This means control tasks can be run in parallel.
The following figure shows a programmable controller that will operate in
multicomputing mode. Each CPU can access the modules assigned to it (FM, CP,
SM).
Configuring Hardware and Communication Connections with STEP 7
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