LD n LDI n

Chapter 5 Instruction Specifications

Item number

Basic instructions-1, 2

Name

Logical operation start (LD, LDI)

 

 

 

 

 

 

 

Ladder format

Condition code

Processing time (s)

Remark

 

n

 

R7F4

R7F3

R7F2

R7F1

R7F0

Average

Maximum

 

 

n

 

DER

ERR

SD

V

 

C

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

z

z

z

z

 

z

 

 

 

 

 

Instruction format

 

 

Number of steps

 

 

0.9

 

 

 

LD

n

 

Condition

 

Steps

 

 

 

 

 

 

LDI

n

 

 

 

1

 

 

 

 

 

 

 

 

 

 

Bit

 

 

Word

 

 

Double word

Constant

 

 

Usable I/O

 

 

R,

TD, SS,

 

WR,

 

 

DR,

Other

 

X

Y

M

CU, CT

WX WY WM

TC

DX DY

DM

n

I/O number

{

{

{

{

 

 

 

 

 

 

 

 

 

Function

 

 

 

 

 

 

 

 

 

 

 

 

 

n

 

 

 

 

 

 

 

 

 

 

 

 

Starts the a-contact logical operation. Enters the continuity state when input is on.

LD n

n

Starts the b-contact logical operation. Enters the continuity state when input is off.

LDI n

Notes

Edge detection (DIF, DFN) cannot be used in respect to LDI.

Pay close attention if the external output is to be monitored when counter input (coincidence output), PWM output or pulse output is set with the PI/O function.

Y100 DIF1

WR0 = WR0 + 1

Y100 will not change while monitored. It will remain the same value previously set using functions such as set/reset.

For example, if Y100 is off, the Y100 status will not change while being monitored and WRO will also remain unchanged.

Program example

X00000

Y00100

LD

X00000

 

 

 

 

OUT

Y00100

 

 

 

 

X00001

Y00101

LDI

X00001

 

 

 

 

OUT

Y00101

 

 

 

 

 

 

 

 

 

 

Program description

When input X00000 is on, output Y00100 is on; when off, the output is off.

When input X00001 is off, output Y00101 is on; when on, the output is off.

5-14

Page 64
Image 64
Hitachi NJI-350B manual Item number, Ladder format Condition code, Remark, Bit Word Double word Constant Usable I/O, Other