KEYENCE Visual KV Series - Manual (Page 293)

6.1 Interrupt Instructions
KV
-300
KV-10/80
3-269
1 6
Chapter 6 Interrupts, High-speed Counters, Positioning Control
Interrupt priority
If two or more interrupts are generated at different timings, interrupt routines are
executed in the order that interrupts are generated.
If two or more interrupts are generated simultaneously, interrupt routines are
executed according to the priority shown below.
CTC0 > CTC1 > CTC2 > CTC3 > 0000 > 0001 > 0002 > 0003
* Note that the above priority differs from that for other KV PLCs (KV-10/16/24/40/
80).
The priority is: 0000 > 0001 > 0002 > 0003 > CTC2 > CTC3 > CTC0 > CTC1.
Note 1: During execution of one interrupt routine, execution of other interrupt rou-
tines is inhibited. (One interrupt routine can be executed inside another interrupt
routine by inserting EI.)
Note 2: If other interrupts are generated during execution of one interrupt routine,
the routines of these interrupts are executed after completion of the first interrupt
routine in the order that they are generated. Note that generation of up to 8 levels of
interrupt nesting or up to 8 individual interrupts can be stored during execution of
interrupt routine. However, generation of an interrupt is ignored if generation of the
same interrupt has already been stored.
Interrupt routine
• Execute EI to enable interrupt.
• Be sure to insert INT between END and ENDH.
• Be sure to shorten the input time constant by using HSP or by turning ON special
utility relay 2813.
Instructions that cannot be used in the INT-RETI block
TMR, TMH, TMS, DIFU, DIFD, W-ON, W-OFF, W-UE, W-DE, STG, JMP, ENDS,
HKEY, ITVL, @xxxx (instruction), C, UDC, SFT
2008
EI
2813
SET
END
INT
XXXXX
RETI
ENDH
KVNKA Chap 06.p65 08.3.11, 0:10 PM 269