Mode switch
The mode switch has two settings:
RUN
In the RUN setting, the CPU 928 processes the user program when the
green RUN LED is lit.
STOP
The CPU 928 goes to the stop state when you switch from RUN to
STOP. The red STOP LED then lights up.
Momentary-contact mode
switch
You can initiate the Overall Reset, Reset and Restart functions with
the momentary-contact mode switch:
OVERALL RESET
Momentary-contact switch down
With an overall reset, all RAM areas are erased and initialized (both
on the CPU and on a RAM submodule).
RESET
Momentary-contact switch up
During a reset, all flags, timers, counters and the process image will be
erased. OB 20 will be invoked. Processing of the user program will
start from the beginning again.
Restart
Momentary-contact switch at midpoint
With a restart, processing of the user program will continue from the
point of interruption. The statuses of flags, timers, counters and the
process image are retained during stoppage of the CPU.
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CPU 928
System Manual
C79000-B8576-C199-03
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