Справочник Пользователя для Mitsubishi Electronics FX3S-MT/ESS
10 Use of High-speed Counters
91
FX
3S
Series Programmable Controllers
User's Manual - Hardware Edition
1
Introduc
tion
2
Features an
d
Par
t N
t N
am
es
3
Produc
t
Introducti
on
4
Sp
ec
ific
atio
ns
5
Ve
rsi
on and
Peri
pheral
pheral
De
vice
s
6
Sy
stem
Confi
gurati
on
7
In
st
alla
tio
n
8
Prep
ara
tion and
Pow
er Supply
Wi
ring
9
Input W
iri
ng
10
Hi
gh
-S
peed
Counters
10.5 Handling of High-speed Counters
10.5.3 2-phase 2-count input
These counters are 32-bit up-count/down-count binary counters.
The operations of the output contact according to the current value are the same as those of the above-
mentioned 1-phase 1-count input high-speed counters.
The operations of the output contact according to the current value are the same as those of the above-
mentioned 1-phase 1-count input high-speed counters.
Examples of program
1) For C251
1) For C251
• While X012 is on, C251 counts the operation of the input
terminals X000 (A-phase) and X001 (B-phase) through
interruption.
interruption.
• While X011 is turned on, the counter is reset when RST
instruction is executed.
• When the current value exceeds the setting, Y002 turns on, and
when the current value becomes lower than the setting, Y002
turns off.
turns off.
• Y003 turns on (down-count) or off (up-count) according to the
counting direction.
2) For C254
• C254 starts counting immediately when the input terminal X006
is turned on while X012 is on. The count input terminals are
X000 (A-phase) and X001 (B-phase).
X000 (A-phase) and X001 (B-phase).
• C254 is reset by X011 on the sequence, and it is reset
immediately when X002 is turned on.
• When the current value exceeds the setting (D1, D0), Y004
operates, and when the current value becomes lower than the
setting, Y004 turns off.
setting, Y004 turns off.
• Y005 turns on (down-count) or off (up-count) according to the
counting direction.
• A 2-phase encoder generates A-phase output and B-phase output between which there is a 90 phase
difference. The high-speed counter automatically counts up or down according to the output as shown
below.
below.
• The down-count/up-count operations of C251 to C255 can be monitored through the ON/OFF operations
of M8251 to M8255.
ON : Down-counting
OFF: Up-counting
OFF: Up-counting
X011
X012
C251
K1234
RST
C251
C251
Y002
M8251
Y003
Main unit
A-phase
input
B-phase
input
X001
X000
X011
X012
C254
D0 (D1)
C254
Y004
M8254
Y005
RST
C254
X000
Main unit
A-phase
input
X001
B-phase
input
X002
X006
External reset
input
External start
input
The setting is (D1, D0)
A-phase
B-phase
+1
+1
Up-counting
-1
-1
Down-counting