KEYENCE Visual KV Series - Manual (Page 292)

6.1 Interrupt Instructions
KV
-300
KV-10/80
3-268
6
Chapter 6 Interrupts, High-speed Counters, Positioning Control
6.1 Interrupt Instructions
6.1.1 Description of Interrupts
Input processing for routine program and interrupt routine
Routine program flow is shown by the thick arrow on the left of Fig.1. In this case,
input signals can be received only during input processing.
Although input time constant can be made shorter by using HSP or by turning ON
special utility relay 2813, input signals can be received only if they are longer than
the duration of one scan time.
When an interrupt initiation input turns ON, the currently running program is sus-
pended to immediately execute the interrupt routine.
During execution of interrupt routine, input signals shorter than one scan time can be
received by the PLC.
Note: To execute INT (interrupt initiation instruction), execute EI first to enable
interrupt, then use HSP (time constant: 25 µs) or turn ON special utility relay 2813
(time constant: 10 µs) to reduce the input time constant.
Types of interrupt
Interrupt by CTC can be generated when the CTC preset value and CTH current
value are equal.
A signal received through any of inputs 0000 to 0003 can generate an interrupt.
Input processing
Output processing
Routine program
execution
Interrupt routine
execution
(00000 to 00005)
(00500 to 00503)
Scan time
Generation of interrupt
Returns to suspended program
at the point of suspension.
Processing of
direct inputs
Processing of
direct outputs
2008
EI
2813
SET or
2002
HSP
0000
EI
2002
Fig. 1
High speed counter comparators CTC0, CTC1, CTC2, CTC3
Input relays 0000, 0001, 0002, 0003
(rising/falling edge selectable)
→
▲
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KVNKA Chap 06.p65 08.3.11, 0:10 PM 268