Omron WS02-SIMC1-E - V1.9 REV 02-2009 Operation Manual page 233

Cycle Time and Time
Calculating Computer Cycle
Time
Process name
(1) Overseeing Proc-
essing
(2) Computing Process
(3) Minimum Cycle Time
Calculation
(4) I/O Refresh
(5) Peripheral Servicing An event service with the CS/CJ-series
Time Elapse in Computer
Cycle Time
In calculating the computer cycle time, the followings are different from that of
the CS/CJ/CP-series CPU Unit.
Process Contents
Back up the I/O memory areas
Process instructions of the user program in
UM1 and UM2. Sum of the execution time
of instructions.
Calculate the cycle time.
Enabling "Minimum Cycle Time" in PLC
Setup will wait for the cycle time to com-
plete with WDT resetting.
Not processed in the computer cycle time. 0 ms
Special I/O Unit, targeting the Network
Communications Unit and the Serial
Communications Unit.
Note: I/O refresh is not included.
Computer cycle time = (1) + (2) + (3) + (5)
Note The computer cycle time may greatly fluctuate depending on the execution
environment such as file access and memory swapping.
The time elapse when Continuous Run in the computer cycle time is the same
as that on the computer.
Time
One step One step
execute execute
Section 9-2
Processing time and Fluctuation
factors
Time for I/O memory areas back-up
Sum of the instruction execution
time for UM1 and UM2
Approximate to 0 for the time when
Minimum Cycle Time is not set.
The additional time for Minimum
Cycle Time = The cycle time
specified as Minimum Cycle Time -
The computer cycle time
((1)+(2)+(4)+(5))
All of the services that occurred in
the cycle are executed regardless
of the setting of Fixed Peripheral
Servicing Time" of PLC Setup.
One step One step
execute execute
Process
Note: The dashed
line shows
the time
elapse in the
virtual cycle
time.
197