Omron CP1L-EL20DR-D, Operation Manual

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Computing the Cycle Time Section 2-7
2-7-8 Interrupt Response Times
Input Interrupt Tasks The interrupt response time for I/O interrupt tasks is the time taken from when
a built-in input has turned ON (or OFF) until the I/O interrupt task has actually
been executed. The length of the interrupt response time for I/O interrupt
tasks depends on the following conditions. (About 0.3ms)
Note (1) The wait time occurs when there is competition with other interrupts. As
a guideline, the wait time will be 6 to 169
μ
s.
(2) I/O interrupt tasks can be executed during execution of the user program
(even while an instruction is being executed by stopping the execution of
an instruction), I/O refresh, peripheral servicing, or overseeing. The inter-
rupt response time is not affected by which of the above processing op-
erations during which the interrupt inputs turns ON. I/O interrupts,
however, are not executed during execution of other interrupt tasks even
if the I/O interrupt conditions are satisfied. Instead, the I/O interrupts are
executed in order of priority after the current interrupt task has completed
execution and the software interrupt response time has elapsed.
The interrupt response time of input interrupt tasks is calculated as follows:
Interrupt response time = Input ON delay + Software interrupt response time
Item Interrupt response time Counter interrupts
Hardware response Rise time: 50
μ
s ---
Fall time: 50
μ
s ---
Software interrupt
response Minimum: 134
μ
s Minimum: 236
μ
s
Maximum: 234
μ
s + Wait
time (See note 1.)
Maximum: 336
μ
s + Wait time
(See note1.)
Input
(Interrupt signal retrieval)
Interrupt task execution
Input interrupt task
response time
Software interrupt response time
Input ON delay
Cyclic task execution
(main program)
Ladder program
execution time
Return time from
input interrupt task
Next interrupt signal
can be accepted.
The time from completing the ladder program in the input
interrupt task until returning to cyclic task execution is 60
μ
s.