Mitsubishi FX3U Series Programming Manual page 173

FX /FX Series Programmable Controllers
3U 3UC
Programming Manual - Basic & Applied Instruction Edition
Cautions
1. Cautions when LDP, LDF, ANDP, ANDF, ORP, or ORF instruction programmed in a same
step is executed twice or more within one operation cycle
When LDP, LDF, ANDP, ANDF, ORP or ORF instruction programmed in a same step is executed twice or
more within one operation cycle, the following operation results:
Programs executed twice or more
• Program between FOR and NEXT instructions
• Program which executes a same subroutine program from two or
more CALL instructions during one operation cycle
• Program which jumps to a label (P) in a smaller step number by CJ
instruction
Operation
1) When a device turns ON from OFF
1st time: LDP, ANDP or ORP instruction turns ON.
2nd time and later: When the device status is same as the time when the instruction was executed last,
the instruction turns OFF.
2) When a device turns OFF from ON
1st time: LDF, ANDF or ORF instruction turns ON.
2nd time and later: When the device status is same as the time when the instruction was executed last,
the instruction turns OFF.
2. Cautions on write during RUN
1) Instructions for falling edge pulse
When write during RUN is completed for a circuit including an instruction for falling edge pulse (LDF,
ANDF, or ORF instruction), the instruction for falling edge pulse is not executed without regard to the ON/
OFF status of the target device of the instruction for falling edge pulse.
When write during RUN is completed for a circuit including an instruction for falling edge pulse (PLF
instruction), the instruction for falling edge pulse is not executed without regard to the ON/OFF status of
the operation condition device.
It is necessary to set to ON the target device or operation condition device once and then set it to OFF for
executing the instruction for falling edge pulse.
2) Instructions for rising edge pulse
When write during RUN is completed for a circuit including an instruction for rising edge pulse, the
instruction for rising edge pulse is executed if a target device of the instruction for rising edge pulse or the
operation condition device is ON.
Target instructions for rising edge pulse: LDP, ANDP, ORP, and pulse operation type applied instructions
(such as MOVP)
Contact ON/OFF status
(while write during RUN is executed)
OFF
*1. PLS instruction is not executed.
Instruction for rising edge pulse
ON
7.5 LDP, LDF, ANDP, ANDF, ORP, ORF
Instruction for falling edge pulse
Not executed
*1
Executed
7 Basic Instruction
FNC 08
K
FOR
X000
FNC 09
NEXT
Not executed
Not executed
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