Operation Processing Of Run, Stop, Pause, And Step-Run - Mitsubishi Electric MELCEC Q Series User Manual

4. CPU MODULE
4.1.2

Operation processing of RUN, STOP, PAUSE, and STEP-RUN

The programmable controller CPU has four kinds of operation status: RUN status, STOP
status, PAUSE status, and step operation (STEP-RUN) status.
Operation processing of programmable controller CPU in each operation status is
explained.
(1)
(2)
(3)
(4)
RUN status operation processing
(a) The repetition of sequence program operation in the order from step 0
(FEND) instruction
(b) When entering the RUN status, the output status saved by STOP is output
depending on the output mode setting of parameter upon STOP
(c) Processing time from switching STOP
program operation is usually one to three seconds, although it may vary
depending on the system configuration.
STOP status operation processing
(a) The termination of operation of the sequence program by the use of the RUN/
STOP key switch, the remote STOP, or at the execution of STOP instruction is
called the STOP status. (Refer to Section 4.3)
(b) When entering the STOP status, it saves the output status and sets all output
points to OFF. Data memories except for output (Y) are retained.
PAUSE status operation processing
(a) The termination of operation of sequence program while retaining output and
data memories is called the PAUSE status. (Refer to Section 4.3)
Step operation (STEP-RUN) operation processing
(a) Step operation is an operation mode wherein operation processing of a
sequence program can be paused/resumed by each instruction from peripheral
device(s). (Refer to Section 4.3)
(b) Since an operation processing is paused while retaining the output and data
memories, condition of the execution can be confirmed.
step 0 is called the RUN status.
RUN to the start of the sequence
4 - 7
END
RUN.