Run. Stop. Pause Operation Processing - Mitsubishi Electric MELSEC-A Series User Manual

I
4. A2CCPU
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IREMARKSI
(1) ": An infinite loop may be caused
if a program execution sequence is jumped to a smaller
step number because of a CJ instruction.
Example:
xo
xo
OJ
An infinite loop is caused if there is no jump in-
struction calling for a jump to a step beyond
step CJ PO to between point PO and step CJ
PO, thereby precluding the execution of the
END
instruction.
•
(1) Data stored in special registers 09017 to 9019
a) 09017: Smallest value of scan time
b) 09018: Present value of scan time
c) 09019: Largest value of scan time
4.1.9 RUN, STOP, PAUSE operation processing
The A2CCPU operates in one of the following three states:
(a) RUN state
The PC CPU operates the sequence program repeatedly from step
to the END (FEND) instruction.
(b) STOP state
All outputs (Y) are turned off and sequence program operation is
not executed.
(c) PAUSE state
Execution of a sequence program is suspended. The status of all
outputs (Y) before entering the PAUSE state are saved .
The PC CPU's operation processing in each operation state is
described below.
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