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4.5.2 Relation between switch operation and the LED indication
(1) Writing a program while the CPU module is stopped:
Follow the procedure below to write a program while the CPU module is
stopped:
1) RUN/STOP key switch: STOP
RUN LED: Off ......CPU module is in STOP mode. Write a program.
2) RUN/STOP key switch: RESET
RUN LED: Off ......CPU module is in STOP mode.
3) RUN/STOP key switch: STOP RUN
RUN LED: Lit .......CPU module is in RUN mode.
POINT
After writing a program (except for online program write), perform reset
operation, and then place the CPU module in the RUN status.
When remote STOP is switched to RUN, the CPU module is not put in
the "PROG CHECK" status but is placed in the RUN status.
(2) Latch clear operation:
Operate the RUN/STOP key switch as follows to execute the latch clear
operation:
1) Turn the RUN/STOP key switch of the CPU module from the "STOP"
position to the "L. CLR" position several times (three or four times) to
flicker the "USER LED" on the CPU module front.
Normally, the LED flickers when the switch is turned several times
(three or four times).
When the "USER LED" flickers, it indicates that latch clear is ready.
2) After the "USER LED" has flickered, turning the RUN/STOP key switch
from the "STOP" position to the "L. CLR" position again executes latch
clear and lights up the "USER LED".
If the "USER LED" comes on for two seconds and then goes off, it
indicates that latch clear is completed normally.
3) To cancel latch clear midway, turn the RUN/STOP key switch to the
"RUN" position to place the CPU module in the RUN state, or turn it to
the "RESET" position to make a reset.
POINT
You can make latch clear valid or invalid for each device via the device
setting in parameter mode.
Instead of using the RUN/STOP key switch, you can also execute the
latch clear operation remotely from the peripheral device. (Refer to the
Q2AS(H)CPU(S1) User's Manual)
