Interrupt Response Times - Omron CP1L CPU UNIT - 03-2009 Operation Manual

Computing the Cycle Time
Input Response
Times
PLC Setup
2-7-8

Interrupt Response Times

Input Interrupt Tasks
Note
96
Calculation Example
Conditions: Input ON delay
Output ON delay
Cycle time
Minimum I/O response time = 1 ms + 20 ms + 0.1 ms = 21.1 ms
Maximum I/O response time = 1 ms + (20 ms × 2) + 0.1 ms = 41.1 ms
Input response times can be set in the PLC Setup. Increasing the response
time reduces the effects of chattering and noise. Decreasing the response
time allows reception of shorter input pulses, (but the pulse width must be
longer than the cycle time).
Input response time
Input
I/O refresh
CPU Unit
Name
Input constants Input response times 00 hex: 8 ms
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.
Item Interrupt response time
Rise time: 50 µs
Hardware response
Fall time: 50 µs
Minimum: 134 µs
Software interrupt
response
Maximum: 234 µs + Wait
time (See note 1.)
(1) The wait time occurs when there is competition with other interrupts. As
a guideline, the wait time will be 6 to 169 µs.
(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
1 ms (normal input with input
constant set to 0 ms)
0.1 ms (transistor output)
20 ms
Input
CPU Unit
Description Settings
10 hex: 0 ms
11 hex: 0.5 ms
12 hex: 1 ms
13 hex: 2 ms
14 hex: 4 ms
15 hex: 8 ms
16 hex: 16 ms
17 hex: 32 ms
---
---
Minimum: 236 µs
Maximum: 336 µs + Wait time
(See note1.)
Section 2-7
Input response time
The pulse width is
less than the input
response time, so
it is not detected.
I/O refresh
Default
00 hex (8 ms)
Counter interrupts