Omron C500-LDP01-V1, Operation Manual

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5-1 Operation in RUN and MONITOR Modes
In RUN mode, the overseeing processes, program execution, and I/O refresh
are repeated cyclically, as shown on the left below.
MONITOR mode processing is identical to RUN mode processing, but Program-
ming Device servicing is performed after program execution, as shown in the
flowchart on the right below. The processing time in MONITOR mode is much
longer than that in RUN mode, because of the Programming Device servicing.
Initialization
Overseeing
processes
Program
I/O refresh
Ladder
P
rogram
I/
O
Uni
t
s
c
a
n
execution
RUN Mode
Initialization
Overseeing
processes
Program
I/O refresh
Ladder
P
rogram
I/
O
Uni
t
s
c
a
n
execution
MONITOR Mode
Programming
Device
servicing
Note In MONITOR mode, data is transferred between the Ladder Program I/O Unit
and the Programming Device during Programming Device servicing. The time
required for Programming Device servicing varies depending on the processes
performed, but the minimum time required is 20 ms.
5-2 Scan Time
It is important to know the scan time of the Unit in order to determine whether or
not the program is operating correctly and to determine if I/O processing is timed
properly.
The explanation below is for the scan time in RUN mode. The scan time will vary
depending on the setting of pin 2 of the back panel DIP switch.
)
Section 5-2