Mitsubishi Electronics FX3S-30MT/ESS-2AD Home Theater Server User Manual


 
10 Use of High-speed Counters
91
FX3S Series Programmable Controllers
User's Manual - Hardware Edition
1
Introduction
2
Features and
Part Names
3
Product
Introduction
4
Specifications
5
Version and
Peripheral
Devices
6
System
Configuration
7
Installation
8
Preparation and
Power Supply
Wiring
9
Input Wiring
10
High-Speed
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.
Examples of program
1) For C251
While X012 is on, C251 counts the operation of the input
terminals X000 (A-phase) and X001 (B-phase) through
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.
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).
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.
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.
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
X011
X012
C251
K1234
RST C251
C251
Y002
M8251
Y003
Main unit
A-phase
input
B-phase
input
X001X000
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