25
Interrupt Functions
Section 1-4
5.
Program the associated program sections.
a) Use INT(89) to refresh the counter SV in counter mode. (See page 28
for more details.)
b) Write an interrupt subroutine within SBN(92) and RET(93) (only when
using count-up interrupts.)
Wiring Inputs
Before using input interrupts, wire the input interrupt signal or count input sig-
nal to the CPU Unit’s input terminal as shown below.
Interrupt Input Signal (Input Interrupt Mode) Wiring Example
Counter 0
Input interrupt 0
1
2
3
Counter1
Counter 2
Counter 3
DM 6628
INTERRUPT
CONTROL
Refresh counter SV
(decrementing mode.)
Generate interrupt.
Only when using interrupts.
Input interrupt (counter mode)
Counter SV
Counter 0
Counter 1
Counter 2
Counter 3
SR 244
SR 245
SR 246
SR 247
Each cycle
Counter PV
−
1
Counter 0
Counter 1
Counter 2
Counter 3
SR 248
SR 249
SR 250
SR 251
Execute specified
subroutine.
PC Setup
Ladder Program
Subroutine
Terminal
Corresponding bit address
B0 (IN0)
IR 00000
A0 (IN1)
IR 00001
B1 (IN2)
IR 00002
A1 (IN3)
IR 00003
Input interrupt signal
CPU Unit
