Omron CJ - PROGRAMMING MANUAL 08-2008 Programming Manual page 222

Interrupt Tasks
Scheduled Interrupt Tasks: Tasks 2 and 3
1,2,3...
Cyclic task
Cyclic task
184
Note For CS-series PLCs, Interrupt Input Unit numbers are in order from 0 to 1
starting on the left side of the CPU Rack. For CJ-series PLCs, Interrupt Input
Unit numbers are in order from 0 to 1 starting from the CPU Unit.
Unit No. →
Operand S (the Second Operand) of MSKS: The bits of FFF7 Hex corre-
spond to the interrupt inputs of the Interrupt Input Unit. Interrupt input num-
bers 0 to 15 correspond to bits 0 to 15.
F Hex
Scheduled interrupt tasks are disabled in the default PLC Setup at the start of
cyclic task execution. Perform the following steps to enable scheduled inter-
rupt tasks.
1. Execute the MSKS (SET INTERRUPT MASK) instruction from a cyclic
task and set the time (cycle) for the specified scheduled interrupt.
2. Set the scheduled interrupt time unit in PLC Setup.
Note The interrupt time setting affects the cyclic task in that the shorter the interrupt
time, the more frequently the task executes and the longer the cycle time.
Example: The following examples shows executed scheduled interrupt task 2
every second.
Interrupt number 4 will be executed
at an interrupt interval of 0064 Hex.
&100
Interrupt
Scheduled interrupt task 2
CS-series PLCs
Interrupt Input Unit
CPU Unit
CPU Unit
0 1
1
F Hex
Scheduled interrupt time unit in PLC
Setup = 10 ms (0.01 s)
Every second
Section 4-3
CJ-series PLCs
Interrupt Input Unit
← Unit No.
0 1
1 1 1 0 1 1
F Hex 7 Hex
1