Mitsubishi MELSEC Q Series Programming Manual page 133

• The X0 and X1 turn ON from OFF at the same time.
END
ON
OFF
X0
ON
X1
OFF
OFF
M0
When using a refresh type CPU module and specifying output (Y) in the PLS instructions,
the ON/OFF status of the device at the execution of the last PLS instruction in the scan is
returned as the output (Y).
(4) PLF instructions using the same device
The PLF instruction turns ON the specified device when the execution command is turned
OFF from ON.
It turns OFF the device at any other time (OFF to OFF, OFF to ON, or ON to ON).
If two or more PLF instructions using the same device are executed in one scan, each
instruction turns ON the device when the corresponding execution command is turned OFF
from ON and turns OFF the device in other cases.
For this reason, if multiple PLF instructions using the same device are executed in a single
scan, a device that has been turned ON by the PLF instruction may not be turn ON during
one scan.
[Ladder]
X0
X1
X0
PLS M0
X1
PLS M0
END
ON
M0 turns ON because X1
goes ON (OFF
ON).
(M0 remains ON.)
M0 turns ON because
X0 goes ON (OFF
ON).
PLF M0
PLF M0
X0
PLS M0
X1
PLS M0
END
M0 turns OFF because X1 status is
other than OFF
ON.
(M0 remains OFF.)
M0 turns OFF because X0 status is other
than OFF
ON.
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