Section 1 PLC Specifications
1-6
1-2 PLC Internal Memory
1-2-3 External interrupt input
Di22 (No. 1 pin of CNIN3) has the external interrupt input function to activate an event task other than ordinary 48V DC input.
(1) Interrupt circuit configuration
External interrupt input
A
N
D
Interrupt activation
%MX10.268.3
%MX10.266.3
%MX10.268.15
Ordinary 48V DC digital input
External
input signal
Latch
CNIN3
No. 1 pin
Interrupt
enabled/diasled
Power-on reset or
reset by interrupt
acceptance
Batch reset of
interrupt factor latch
(2) Assigning the intterupt activation flag to an event task
To activate an event task by an external interrupt signal, it is necessary to assign the external interrupt activation flag
(%MX10.266.3) to an event variable.
Interrupt input is held temporarily by an internal latch circuit. The default of the latch circuit status is “0” (reset).
To enable interrupt, set the external interrupt enable flag (%MX10.268.3) to ON. The interrupt is disabled (the flag is set OFF)
by default.
If the interrupt is enabled when an interrupt input is already held, the interrupt is activated immediately.
To reset a latch circuit, set the system memory (%MX10.268.15) to ON. When the flag is set to ON, all the latch circuits will
be reset. The latch circuits for comparison match interrupts of high-speed counter are reset at the same time.
When an interrupt program is started, the interrupt latch circuits are reset automatically.
