Mitsubishi Q00JCPU User Manual page 485

9
DEVICE EXPLANATION
(c) Resetting the counter
[Ladder example]
[Counter reset timing]
Counter current values are not cleared even if the OUT C
OFF. Use the RST C instruction to clear the counter's current value and switch
the contact OFF.
The count value is cleared and the contact is switched OFF at execution of when
the RST C instruction.
X0
END
Sequence
program
ON
X0 OFF
Execution
RST C0 OFF
instruction
Count value cleared
& contact OFF
Diagram 9.31 Counter resetting
1) Precautions for resetting the counter
When the RST C instruction is executed, the coil of C
If the execution condition of the OUT C
of the RST C instruction, the coil of C
OUT C instruction to update the current value (increment the count value by
1).
[Ladder example]
Diagram 9.32 Counter resetting ladder example
In the above ladder example, when M0 turns from OFF to ON, the coil of C0
turns ON, updating the current value. When C0 reaches the preset value
finally, the contact of C0 turns ON, and the execution of the RST C0 instruction
clears the current value of C0. At this time, the coil of C0 also turns OFF.
When M0 is still ON in the next scan, the current value is updated since the
coil of C0 turns from OFF to ON at the execution of the OUT C0 instruction.
(The current value turns to 1.)
RST C0
RST C0 END RST C0
instruction is still ON after execution
is turned ON at the execution of the
M0
C0
RST C0
9.2 Internal User Devices
9.2.11 Counter (C)
instruction switches
END RST C0
Count value cleared
& contact OFF
also turns OFF.
K10
C0
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