Mitsubishi Electric MELSEC iQ-R Series, Programming Manual

Page: 165 / 2110

5 SEQUENCE INSTRUCTIONS
5.1 Contact Instructions
163
5
Setting data
■
Description, range, data type
• In safety programs executed by the Safety CPU, only safety devices and safety labels of data types described in the table
can be used.
■
Applicable devices
• In safety programs executed by the Safety CPU, only the following safety devices and constants can be used.
Processing details
■
LDP, LDF
• LDP is a rising edge pulse operation start instruction, and turns on only at the rising edge (off to on) of the specified bit
device. When a bit-specified word device is used, this instruction turns on only when the specified bit changes from 0 to 1.
In cases where there is an LDP instruction only, it acts identically to instructions for conversion to pulses that are executed
during on (

P).
The following figure shows an example when a ladder using the LDP instruction is replaced with a ladder not using the LDP
instruction.
• LDF is a falling edge pulse operation start instruction and turns on only at the falling edge (on to off) of the specified bit
device. When a bit-specified word device is used, this instruction turns on only when the specified bit changes from 1 to 0.
• If the LDP instruction is used in the program written in ST language or FBD/LD, ENO turns on at the rising edge (off to on)
of the specified bit device (s).
• If the LDF instruction is used in the program written in ST language or FBD/LD, ENO turns on at the falling edge (on to off)
of the specified bit device (s).
• If the LDP or LDF instruction is used in the program written in ST language, set EN to be always on.
• If the LDP or LDF instruction is used in the program written in FBD/LD, use a left rail or a variable/constant which is always
on for EN.
Operand Description Range Data type Data type (label)
(s) Device used as a contact

Bit ANY_BOOL
EN Execution condition

Bit BOOL
ENO Execution result  Bit BOOL
Operand Bit Word Double word Indirect
specification
Constant Others
(DX)
X, Y, M, L,
SM, F, B, SB,
FX, FY J  \  T, ST, C, D, W,
SD, SW, FD, R,
ZR, RD U  \G  , J  \  ,
U3E  \(H)G 
Z LT, LST,
LC LZ K, H E $
(s)            
Operand Bit Word Constant
SA\X, SA\Y, SA\M, SA\SM, SA\B SA\T, SA\ST, SA\C, SA\D, SA\W, SA\SD K, H
(s)   
D0
X0
X0
X0
X0
M0
MOVP K0 D0 MOV K0
PLS M0