1-Phase 2-Count Input - Mitsubishi Electric MELSEQ FX3S Series User Manual

FX Series Programmable Controllers
3S
User's Manual - Hardware Edition
• C235 is set to the up-count or down-count mode through interruption by the count input X000.
• When the current value increases from -6 to -5, the output contact is set, and when the value decreases
from -5 to -6, it is reset.
• The current value increases and decreases regardless of the operation of the output contact. However,
when the counter's value increments from 2,147,483,647, it changes to -2,147,483,648. In the same
manner, when it decrements from -2,147,483,648, it changes to 2,147,483,647. (This type of counter is
called a ring counter.)
• When RST instruction is executed after the reset input X011 turns on, the current counter's value resets to
0, and the output contact is restored.
• The current value, output contact operation and reset status of counters are backed up (kept) even if the
power is turned off.

10.5.2 1-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 C246
X011
X012
Up-counting
input
X000
Main unit
2) For C249
X011
X012
Down-counting
Up-counting
input
X000
90
RST C246
D2 (D3)
C246
The setting is (D3, D2)
Down-counting
input
X001
RST C249
K1234
C249
External start
input input
External reset
input
X001 X002 X006
Main unit
• While X012 is on, C246 increments the value when the
input terminal X000 switches from OFF to ON and
decrements the value when the input terminal X001
switches from OFF to ON.
• The down-count/up-count operations of C246 to C250 can
be monitored through the ON/OFF operations of M8246 to
M8250.
ON : Down-counting
OFF: Up-counting
• While X012 is on, C249 starts counting immediately when
the input terminal X006 turns on. The up-counting input
terminal is X000, and the down-counting input terminal is
X001.
• C249 can be reset on the sequence by X011. For C249,
X002 is allocated as reset input. When X002 turns on, C249
is immediately reset.
• The down-count/up-count operations of C246 to C250 can
be monitored through the ON/OFF operations of M8246 to
M8250.
ON : Down-counting
OFF: Up-counting
10 Use of High-speed Counters
10.5 Handling of High-speed Counters