About the comparison instructions, Comparison instructions overview – Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) User Manual

Page 153

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Chapter 9
Using Comparison Instructions

9–2

Comparison Instructions

HHP

Display

Mnemonic

Function

Code

Name

Purpose

Page

MEQ

LD MEQ

68

Mas e

es

r i s f

a es

see

e er e are e a

ares

MEQ

AND MEQ

69

Masked
Comparison for

a

Test portions of two values to see whether they are equal. Compares
16-bit data of a source address to 16-bit data at a reference address

r

a as

9–9

MEQ

OR MEQ

70

Equal

through a mask.

9–9

LIM

LD LIM

71

LIM

AND LIM

72

Limit Test

Test whether one value is within the limit range of two other values.

9–10

LIM

OR LIM

73

Comparison instructions are used to test pairs of values to condition the
logical continuity of a rung. As an example, suppose a LES instruction is
presented with two values. If the first value is less than the second, then the
comparison instruction is true.

To learn more about the compare instructions, we suggest that you read the
Compare Instructions Overview that follows.

The following general information applies to comparison instructions.

Entering the Instruction

The following items apply when entering the instructions:

Whenever you see asterisks on the display, the HHP is waiting for data
entry (i.e., a number).

You can return to previously entered operands by pressing this key:

Then if you want to edit that operand, press

DEL

or

FUN-DEL

and enter

new parameters. Press

ENT

to accept the operand and move on to the next

one. Once the entire instruction is entered, if you want to edit the
instruction’s parameters you must go into the overwrite mode. (See page
17–4.)

About the Comparison
Instructions

Comparison Instructions
Overview

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