10.1.7
Starting up in the
Multiprocessor Mode
Starting up individual CPUs
CPU 948 Programming Guide
C79000-G8576-C848-04
You can start the coordinator for multiprocessing in one of the
following ways:
Initial status:
The RUN/STOP switch of each CPU is
in the RUN position. The RUN/STOP switch
on the coordinator is in the STOP position.
Handling:
Move the RUN/STOP switch on the coordinator
from STOP to RUN. (Starting the S5-155U in
multiprocessor operation simply by starting the
coordinator is possible only if the coordinator
itself caused the controller to change to the STOP
mode).
or:
Initial status:
The RUN/STOP switch of each CPU is in
the RUN position as well as that of the
coordinator.
Handling:
Use the PG START function to start the
CPU that caused the STOP in the required
restart type.
The restart type that each CPU now uses depends on what took place
while the CPU was in the STOP mode. Some CPUs need MANUAL
WARM RESTART, others, a COLD RESTART.
If the CPU settings were not changed in that time, execute a manual
warm restart.
Note
Due to the various restart types, incorrect signal statuses can be
transferred from one CPU to another via the IPC flags. This could
happen if the controller was in cycle prior to entering the STOP
mode. Prevent this by programming the start-up organization
blocks OB 20, OB 21 and OB 22 appropriately.
You can call special function block OB 223 to check whether the
start-up types of all the CPUs are the same (refer to Chapter 6).
Multiprocessor Mode
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