Computing The Cycle Time; Cpu Unit Operation Flowchart - Omron CP1L Operation Manual

Computing the Cycle Time

2-7 Computing the Cycle Time
2-7-1

CPU Unit Operation Flowchart

Sets error flags.
ERR/ALM
indicator ON or
flashing?
ON (fatal error)
The CPU Unit processes data in repeating cycles from the overseeing pro-
cessing up to peripheral servicing as shown in the following diagram.
Power ON
Checks Unit connection status.
Checks hardware and user
program memory.
Error
Check OK?
Flashing
Executes user program (i.e.,
(nonfatal error)
executes READY cyclic tasks).
End of program?
Waits until the set cycle time
has elapsed.
Calculates cycle time.
Performs I/O refreshing.
Services peripheral devices.
Startup
initialization
Overseeing
processing
Normal
Program
execution
NO
YES
Cycle time
calculation
I/O
refreshing
Peripheral
servicing
Section 2-7
PLC
cycle
time
89