785
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
35 Interrupt Function and Pulse Catch Function
35.2 Common Items
31
FN
C
275-FN
C
279
Da
ta
Tr
ans
fe
r 3
32
FN
C
280
-F
N
C
28
9
H
igh Speed
Pr
oces
si
ng 2
33
FN
C
290-FN
C
299
Ext
ensi
on Fi
le
R
egi
st
er
34
SF
C
•S
T
L
Pr
o
g
ra
m
m
in
g
35
In
te
rru
p
t
Funct
ion
36
Sp
e
cia
l De
vic
e
37
E
rro
r C
o
d
e
A
V
e
rs
ion U
p
In
fo
rm
a
tio
n
B
Ex
ec
ut
ion Ti
m
e
s
C
Appl
ic
ab
le
In
st
ru
ct
ion Li
st
2) Timing chart
Example in which latched outputs are reset (countermeasures)
1) Program example
2) Timing chart
Execution of interrupt
program I001 triggered
by X000
X001
Current
value of C0
1
2
3
Counter is
reset
Because the C0 reset
instruction is valid, the current
value of C0 remains unchanged
even if a pulses are input.
C0 remains reset
Y007 is being output
Outputs are latched.
RST
C0
Y007
Interrupt program
RST
C0
X002
FNC 06
FEND
RST
C0
RST
Y007
Program to reset Y007 at an arbitrary
timing.
Program to deactivate the preceding
C0 reset instruction inside the
subroutine.
B
M8001
RUN monitor
(normally OFF)
A
Y007
X001
C0
K10
M8000
FNC 05
IRET
I001
FNC 04
EI
Step 0
X001
Current
value of C0
1
2
3
Y007 is reset
RST
C0
Y007
1
2
3
4
X002
Execution of interrupt
program I001 triggered
by X000
Interrupt program
Counter is reset
(part A in above
program).
Counter reset instruction is deactivated
(part B in above program).