Rockwell Automation 1772-LS, 1772-LSP, D17726.8.6 User Manual

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AllenBradley

1772 Mini PLC2/05 Processor

(Cat. No. 1772-LS, LSP)

Programming and Operations Manual

Important User Information

Because of the variety of uses for this product and because of the differences between solid state products and electromechanical products, those responsible for applying and using this product must satisfy themselves as to the acceptability of each application and use of this product. For more information, refer to publication SGI-1.1 (Safety Guidelines For The Application, Installation and Maintenance of Solid State Control).

The illustrations, charts, and layout examples shown in this manual are intended solely to illustrate the text of this manual. Because of the many variables and requirements associated with any particular installation, Allen-Bradley Company cannot assume responsibility or liability for actual use based upon the illustrative uses and applications.

No patent liability is assumed by Allen-Bradley Company with respect to use of information, circuits, equipment or software described in this text.

Reproduction of the contents of this manual, in whole or in part, without written permission of the Allen-Bradley Company is prohibited.

Throughout this manual we make notes to alert you to possible injury to people or damage to equipment under specific circumstances.

ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property damage or economic loss.

Attention helps you:

- Identify a hazard

- Avoid the hazard

- recognize the consequences

Important: Identifies information that is critical for successful application and understanding of the product.

Summary of Changes

This release of the publication contains updated information:

For this updated information: See:

revised conventions chapter 1

clarification to switch settings for 1772LSP chapter 3

description of keys on keytop overlay (1770KCB) chapter 3

corrections to the discussion about automatic restart

corrections to the discussion about program control

addition of ZCL to glossary appendix B

new format all chapters and appendices

chapter 18

To help you find new information in this publication, we have included change bars as shows to the left of this paragraph.

Part

Hardware Overview

Industrial Terminal

(rear view)

Channel A PLC2 Family

1 Before You Begin 2 An Introduction to Programmable Controllers 3 Hardware

MiniPLC2/05

Program Panel Interconnect Cable

Interface

RUN

P R O C

FAULT

MEMORY

STORE

AB

INTFC

MINI PLC2/05

W/O Power Supply

P R O

P/S

ACTIVE

MEMORY

STORE

P/S

PARALLEL

AB

POWER

OFF I.0A 125V

SLOW BLOW

120V

GND

MINI PLC2/05

W Power Supply

RUN

FAULT

INTFC

4 Memory Organization 5 Scan Theory 6 Relay-type Instructions 7 Program Control Instructions 8 Timers and Counters 9 Data Manipulation Instructions 10 Math Instructions 11 Data Transfer File Instructions 12 Sequencers 13 Jump

Instructions and

Subroutines 14 Block Transfer 15 Selectable Timed Interrupt

Part

Memory / Instruction Set

Data Table

Main Program

User Program

Subroutine

Message Storage Area

110

110 110

110

010

16 Program Editing

Part

Program Editing

( )

( P )

FOR

USE WITH PLC2 F

 1982 ALLENBRADLEY 97534302

AMILY CAT

. NO. 1770 KCB

Part

Report Generation /

Application Programming Techniques

17 Report Generation 18 Programming Techniques

MS.0

198 MESSAGES SELECTED

MESSAGE CONTROL WORDS ( ENTER 5 DIGIT WORD ADDRESS)

ADDRESS 00200 – 00227

MESSAGE MESSAGE MESSAGE MESSAGE MESSAGE MESSAGE CONTROL NUMBERS CONTROL NUMBERS CONTROL NUMBERS WORDS WORDS WORDS

027 1–6

00200 010–017 00210 1010–1017 00220 2010–2017 00201 110–117 00211 1110–1117 00210 2110–2117 00202 210–217 00212 1210–1217 00203 310–317 00213 1310–1317 00204 410–417 00214 1410–1417 00205 510–517 00215 1510–1517 00206 610–617 00216 1610–1617

19 Program Troubleshooting

Part

Program Troubleshooting

hr.mn.sec.

OFF or ON 00:00'00.00

ON 00:00:00.00OFF 00:00:00.00ON 00:00:00.00

On Time

WORD ADDRESS: 0030

BIT NO.: 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00

STATUS : 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

FORCE :

Off Time

On Time

Part

Appendices

A Number Systems B Glossary C Quick Reference Index

Key Sequences:

[SEARCH]

[Instruction key]

(Address)

[SEARCH]

[5][3]

[

←] or [→]

[1] or [0]

This appendix contains defines terms and abbreviations that because of their complexity or recent introduction are not widely understood. These terms are:

AC Input Module

An I/O module that converts various AC signals originating at user devices to the appropriate logic level signal for use within the processor.

AC Output Module

An I/O module that converts the logic level signal of the processor to a usable output signal to control a user AC device.

[SEARCH]

[5][3]

[Address]

[

↑]or[↓]

357

3 x 82 = 192

= 40

5 x 8

= 7

7 x 8

192

239

23910 = 357

Summary of Changes

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Before You Begin 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

An Introduction to Programmable Controllers 21. . . . . . . . . .

Hardware 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Memory Organization 41. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Scan Theory 51. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Relaytype Instructions 61. . . . . . . . . . . . . . . . . . . . . . . . . . .

Program Control Instructions 71. . . . . . . . . . . . . . . . . . . . . .

Timers and Counters 81. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Data Manipulation Instructions 91. . . . . . . . . . . . . . . . . . . . .

Math Instructions 101. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ThreeDigit Expanded Chapter Summary 1021

Math

101. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

104. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Data Transfer File Instructions 111. . . . . . . . . . . . . . . . . . . . . .

Types

of File Instructions

111. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequencers 121. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Comparison Chapter Summary 1222

with File Instructions

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

121. . . . . . . . . . . . . . . . . . . . . . . .

Jump Instructions and Subroutines 131. . . . . . . . . . . . . . . . . .

Label Instruction 133. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Subroutine Area Instruction 134 Chapter Summary 137

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table of Contentsii

Block Transfer 141. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Selectable Timed Interrupt 151. . . . . . . . . . . . . . . . . . . . . . . . .

Program

Rules

Editing

for Editing Instructions

Report Generation 171. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming Techniques 181. . . . . . . . . . . . . . . . . . . . . . . . .

Program Troubleshooting 191. . . . . . . . . . . . . . . . . . . . . . . . .

Number Systems A1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Glossary B1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Quick Reference C1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

161. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

161. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter

Before You Begin

Important: Read this chapter before you use the Mini-PLC-2/05 Processor (cat. no. 1772-LS,-LSP). It tells you how to use this manual.

Purpose

To the Reader

The Mini-PLC-2/05 processor is functionally similar to the Mini-PLC-2/15 processor. The Mini-PLC-2/05 processor has some additional features:

selectable timed interrupt memory protect switch fast I/O scan user selectable PROM/RAM backup 3K memory expanded mathematics

However, this processor does not have a mode select switch.

This manual is divided into six parts (Table 1.A).

Table 1.A

of the MiniPLC2/05 Processor Programming and Operations Manual

Parts

Part Title What's Covered

A Hardware Overview basic theory concerning the hardware features available when using

this processor

B Memory/Instruction Set describes the memory and informs you about the techniques you can

use when programming this processor

C Program Editing how to edit your program once it has been entered into the memory

D Report Generation/Application

Program Techniques

E Program Troubleshooting acts as a guide so you can minimize production down time

F Appendices contains tables and reference information useful when programming

how to do report generation and use special program techniques

your processor

This manual is procedure oriented. It tells you how to program and operate your Mini-PLC 2/05 Processor. If you need to learn more about the Mini-PLC-2/05 Processor, contact your local Allen-Bradley representative or distributor.

11

Chapter 1

Before You Begin

Vocabulary

Conventions

To make this manual easier to read and understand, we refer to the:

We Refer to the: As the:

MiniPLC2/05 Processor processor

Electrically Erasable Programmable Read Only Memory

Execute Auxiliary Function EAF

Complementary Metal Oxide Semiconductor Random Access Memory

Industrial Terminal (cat. no. 1770T3) 1770T3 terminal

EEPROM

CMOS RAM

A glossary at the back of this manual clarifies technical terms.

A word equals 16 bits; a byte equals 8 bits (1/2 a word).

Words in [ ] denote the key name or symbol. Words in < > denote information that you must provide - for example, an address value.

Word values are displayed in:

decimal (0-9) for timers, counters, and mathematics

010

Decimal

030

CTU

PR 555 AC 123

hexadecimal values (0-9, A-F) for gets and puts

010

011 012

Hexadecimal

030

00FFF 123

Important: Numbers 0-9 are displayed the same in decimal and hexadecimal.

octal for byte values

0101 030

237

Octal

12

Chapter 1

Before You Begin

Keystroke directions are divided into two columns:

tells you what key or keys to press

Related Publications

tells you the processor’s action.

The publication index, publication SD 499, lists all available publications to further inform you about products related to the Mini-PLC-2/05 processor. Consult your local Allen-Bradley distributor or sales engineer for information regarding this publication or any needed information.

13

Chapter

An Introduction to Programmable Controllers

Chapter Objectives

Traditional Controls

In this chapter, you review general fundamentals common to our programmable controllers. This chapter:

describes what a programmable controller does describe the four major sections of a programmable controller describes how the four major sections of a programmable controller interact gives an example of a simple program

You are probably familiar with the traditional methods of machine control.

Relays

Machine

Sensing Devices

Sensing devices located on the machine detect changes in the machine’s condition. For instance, a part arriving at a work station contacts and closes a limit switch, the sensing device. As a result, an electrical circuit is completed and a signal is sent to the control panel.

Control Panel

Output Devices

11591

At the control panel, the electrical signal enters a bank of relays or other devices, such as solid state modules. Circuits within the control panel open or close causing additional electrical signals to be sent to output devices at the machine. For example, a relay energized by the limit switch closed by the arriving part may complete another circuit energizing the output device, a clamp, which secures the part at the work station.

21

Chapter 2

An Introduction to Programmable Controllers

Programmable Controls

Programmable controllers can perform many of the functions of traditional controls. Sensing devices report to the processors. The output devices at the machine operate the same as they would with traditional controls.

Programmable Controller

Conditons

Machine

Sensing Devices

Control Panel

Output Devices

Action Command

11592

The field wiring between the machine and the control panel provides electrical paths from the sensing devices to the control panel, and from the control panel to the output devices.

However, inside the control panel you’ll find a programmable controller rather than relays or discrete solid state devices. Instead of wiring those devices and relays together to produce a desired response, you simply tell your programmable controller by means of a program how you want it to respond to the same conditions.

The Four Major Sections

22

Programming is telling your programmable controller what you want it to do. A program is nothing more than a set of instructions you give the programmable controller telling it how to react to different conditions within the machine.

Let’s take a closer look at a typical programmable controller. It usually consists of four major sections:

processor input output power supply

Power Supply

Processor

(Decision Making)

Chapter 2

An Introduction to Programmable Controllers

Information

Input Output

Limit, Proximity, Pressure,

•

Temperature Switches

•

Push Buttons

•

Logic

•

BCD

•

Analog

Action

Solenoids•

•

Motor Starters

•

Indicators

•

Alarms

•

Logic

•

BCD

•

Analog

Processor

The first section of a programmable controller is the processor. The processor might be called the “brains” of the programmable controller. It is divided into halves:

central processing unit memory

CPU

Processor Section

Data

Table

Program

Storage

Message Storage

Memory

Central Processing Unit

The central processor unit (CPU) makes decisions about what the processor does.

23

Chapter 2

An Introduction to Programmable Controllers

Memory

Memory serves three functions:

stores information in the data table that the CPU may need stores sets of instructions called a program stores messages

Data Table

The area of memory where data is controlled and used, is called the data table. The data table is divided into several smaller sections according to the type of information to be remembered. These smaller sections are called:

output image table input image table timer/counter storage

Data Table

Output Image Table

Input Image Table

Timer/Counter

Storage

At this time, we will only discuss the input and output image tables and program storage.

I/O Image Tables

The input image table reflects the status of the input terminals. The output image table reflects the status of bits controlled by the program.

Each image table is divided into a number of smaller units called bits. A bit is the smallest unit of memory. A bit is a tiny electronic circuit that the processor can turn on or off. Bits in the image table are associated with a particular I/O terminal in the input or output section.

When the processor detects a voltage at an input terminal, it records that information by turning the corresponding bit on. Likewise, when the processor detects no voltage at an input terminal, it records that information by turning the corresponding bit off. If, while executing your program, the CPU decides that a particular output terminal should be turned on or off, it records that decision by turning the corresponding bit on or off. In other words, each bit in the I/O image tables corresponds to the on or off status of an I/O terminal.

24

When people who work with personal computers talk about turning a bit on, they use the term “set.” For example - “The processor sets the bit” means “turns it on.” On the other hand, we use the term “reset” when we talk about turning the bit off - for example, “The processor reset the bit.”

Chapter 2

An Introduction to Programmable Controllers

Picture memory as a page that has been divided into many blocks. Each block represents one bit. Since each bit is either on or off, we could show the state of each bit by writing “on” or “off” in each block. However, there is an easier way. We can agree that the numeral one (1) means on and that the numeral zero (0) means off. We can show the status of each bit by writing 1 or 0 into the appropriate block. For example, you might hear expressions like, “The CPU responded by writing a one into the bit when the limit switch closed.” Of course, the processor didn’t really write a one into memory: it simply set the bit by turning it on.

When the I/O device is: The bit status is said to be:

off

set

off

reset

If you heard the expression, “The processor wrote a zero into that bit location.” What actually happened? If you said the processor merely reset the bit by turning it off, you’re right.

Program Storage

The other major area of memory, program storage, takes up the largest portion of memory. You’ll recall that this is where your instructions to the programmable controller are stored. You’ll also recall that this set of instructions is called a program.

Program Language

A program is made up of set of statements. Each statement does two things:

It describes an action to be taken. For instance, it might say, “Energize motor

starter number one.”

It describes the conditions that must exist in order for the action to take place.

Statement

Program

Statement

Program Storage Area

of Memory

ActionConditions

Program Statement

25

Chapter 2

An Introduction to Programmable Controllers

For example, you may want this action to take place: ”Whenever a certain limit switch closes.” So your condition could be: “If limit switch number two is closed,...” The action would be: “energize motor starter number one.” The entire statement is then: “If limit switch number two is closed, then energize motor starter number one.” Therefore, when limit switch number two at the machine closes, the programmable controller energizes the motor starter. If limit switch number two does not close, the programmable controller does not energize the motor starter. Thus, when limit switch number two opens, the programmable controller de-energizes the motor starter because that action is implied in the statement.

A program is made up of a number of similar statements. Typically, there is one statement for each output device on the machine. Each statement lists the conditions that must be met and then, states the action to be taken.

Instructions

Each condition is represented by a specific instruction; therefore, each action is represented by a specific instruction. These instructions tell the processor to do something with the information stored in the data table.

Some instructions tell the processor to read what’s written in the image table. When the processor is instructed to read from an image table, it examines a specific bit to see if a certain I/O device is on or off.

Other instructions tell the processor to write information into the image table. When the processor is instructed to write into the output image table, it writes a one or a zero into a specific bit. The corresponding output device will turn on or off as a result.

Input

The second section is the input, which serves four very important functions:

termination indication conditioning isolation

Termination

The input provides terminals for the field wiring coming from the sensing devices on the machine.

Indication

The input of most modules also provides a visual indication of the state of each input terminal with indicators. The indicator is on when there is a voltage applied to it terminal. It is off when there is no voltage applied to its terminal. Since the indicator reveals the status of its terminal, it’s usually called an input status indicator.

26

Chapter 2

An Introduction to Programmable Controllers

You should also notice another important characteristic of input indicators. They are only associated with terminals used for wiring sensing devices to the input section. The terminal that’s used to provide a ground for the sensing circuits has no indicator.

Conditioning

Another function of the input is signal conditioning. The electrical power used at the machine is usually not compatible with the signal power used within the programmable controller. Therefore, the input section receives the electrical signal from the machine and converts it to a voltage compatible with the programmable controller’s circuitry.

Isolation

The input isolates the machine circuitry from the programmable controller’s circuitry. Isolation helps protect the programmable controller’s circuitry from unwanted and dangerous voltage levels that may occur occasionally at the machine or in the plant’s wiring system.

Output

The third section is the output, which serves functions similar to those of the input image table:

termination indication conditioning isolation

Termination

The output provides terminals for the field wiring going to the output devices on the machine.

Indication

The output of most modules provides a visual indication of the selected state of each output device with indicators.

The output status indicator is on when the output device is energized. A common term applied to either input status indicators or output status indicators is I/O status indicators. I/O stands for either input or output.

In addition, the output section of modules with fuses has blown fuse indicators. When one of the fuses in the group opens, the blown fuse indicator lights.

Conditioning

The output conditions the programmable controller’s signals for the machine. That is, it converts the low-level dc voltages of the programmable controller to the type of electrical power used by the output devices at the machine.

27

Chapter 2

An Introduction to Programmable Controllers

Isolation

The output isolates the more sensitive electronic circuitry of the programmable controller from unwanted and dangerous voltages that occasionally occur at the machine or the plant’s wiring system. Some situations require additional external protection.

Power Supply

The fourth section is the power supply. It provides a low level dc voltage source for the electronic circuitry of the processor. It converts the higher level line voltages to low level logic voltages required by the processor’s electronic circuitry.

Control Sequence

Let’s look at a simple example to see the sequence of events that take place in controlling a machine with a programmable controller (Figure 2.1). Suppose you are making a part. The motor driven conveyor carries a unit to the work area. The limit switch detects wen the part arrives at the work area. When that happens, we want the conveyor to stop so you can work on the part.

Figure 2.1

Simplified Example of a Machine with a Programmable Controller

Controller

Input Output

Conveyor

Motor

Limit Switch

28

Conveyor

Unit

11594

Notice how the limit switch and motor are wired to the programmable controller. The limit switch, wired to terminal 02, is normally-closed. The arriving part will open the switch. Therefore, the program statement controlling the conveyor motor must read: “If there is voltage at input terminal 02 (limit switch), then energize output terminal 02 (conveyer motor).” The conveyor motor is wired to output terminal 02.

Chapter 2

An Introduction to Programmable Controllers

Important: Figure 2.1 is for demonstration purposes only. We do not show the associated wiring, a motor starter, or an emergency stop button.

Since the limit switch is wired normally-closed, the conveyor motor will run until the arriving part opens the switch. At that time, the condition for energizing the motor is not longer met. Therefore, the motor is de-energized.

When the condition is met, we say it is true. When the condition is not met, we say it is false. There may be more than one condition which must be met before an action is executed. When all the conditions are met, the action is executed and we say the statement is true. When one or more of the conditions are false, the action is not executed and we say the statement is false.

Scan Sequence

On power up, the processor begins the scan sequence (Figure 2.2) with the I/O scan. During the I/O scan, data from input modules is transferred to the input image table. Data from output image table is transferred to the output modules.

29

Chapter 2

An Introduction to Programmable Controllers

Figure 2.2

Sequence

Scan

I/O

Scan

Program

Scan

Output Image Table

Copy output image table status into output terminal circuits.

Input

Terminals

Copy input terminal status into input image table.

Program Statement

Output

Terminals

Input Image Table

210

Execute each program rung in sequence, writing into bits in the data table, including the output image table.

11597

Chapter 2

An Introduction to Programmable Controllers

Next, the processor scans the program. It does this statement by statement. Each statement is scanned in this way:

1. For each condition, the processor checks, or “reads,” the image table to see

if the condition has been met.

2. If the set of conditions has been met, the CPU writes a one into the bit

location in the output image table corresponding to the output terminal to be energized. On the other hand, if the set of conditions has not been met, the processor writes a zero into the bit location, indicating that the output terminal should not be energized.

Here is a simple explanation of the program. If input 02 is on, then turn on output 02. If input 02 is off, then turn off output 02. The program could be written this way:

If (condition) Then (action)

Input bit 02 is on Turn output bit 02 on

In this example, the processor reads a 1 at input bit location 02 and knows that the condition has been met. The processor then carries out the action instruction by writing a 1 into output bit location 02.

If there were more statements in the program, the processor would continue in this same manner scanning each statement and executing each instruction until it reached the end of the program. Statement by statement, the processor would write a 0 or a 1 into an output bit as directed by the program. Then, the processor would read specific image table bits to see if the proper set of conditions were met. After reading and executing all program statements, the processor scans the output image table and energizes or de-energizes output terminals. The processor then goes to the input modules to update the input image table.

Now the entire process is repeated. In fact, it’s repeated over and over again, many times a minute. Each time, the processor sets or resets output bits. Next, the processor senses the status of the input terminals. Finally, the processor scans the program and orders each output terminal on or off according to the state of its corresponding bit in the output image table.

When forcing is attempted, the processor’s I/O scan slows down to do the forcing (see chapter 19). When forcing is terminated, the processor automatically switches back to the faster I/O scan mode.

When this example begins, the processor is energizing output terminal 02 because output bit 02 is on.

When the part is conveyed to the work station, it turns the limit switch off. When the limit switch is off, there is no voltage at input terminal 02. The processor scans the input image table, senses no voltage, and responds by writing a zero into bit 02 in the input image table.

211

Chapter 2

An Introduction to Programmable Controllers

The processor scans the program. Our program states that if (conditions) input bit 02 is on, turn on output 02. If input bit 02 is off then output bit 02 is off. Since the alter condition is not true, the processor turns off output bit 02.

When the processor next scans the output image table, it sees the zero in output bit 02 and responds by de-energizing output terminal 02. The action causes the conveyor to stop.

Chapter Summary

We reviewed fundamentals common to A-B processors. The next chapter summarizes hardware features of the Mini-PLC-2/05 processors.

212

Hardware

Chapter

Chapter Objectives

Major Features

General Features

This chapter is a summary of the Mini-PLC-2/05 Processor Assembly and Installation Manual, publication 1772-6.6.6. In this chapter, you will read about:

major features general features hardware features optional features

A complete processor system consists of the following major components:

Mini-PLC-2/05 processor I/O chassis power supply I/O modules (up to 16 modules) industrial terminal (cat. no. 1770-T3)

The processor has the following features:

3K CMOS RAM memory 488 timers up to 2944 word capacity data table (23 blocks) ladder diagram and functional block instruction set four function arithmetic capabilities remote mode selection on-line programming block transfer capability 70 message storage (with the 1770-T3 terminal only) 198 message storage with the PLC-2 Family Report Generation Module

(catalog number 1770-RG)

data highway compatibility selectable timed interrupts expanded math capability

3-1

Chapter 3

Hardware

Hardware Features

MiniPLC2/05 Processor (cat. no. 1772LS)

The Mini-PLC-2/05 Processor (cat. no. 1772-LS) comes equipped with the following hardware features (Figure 3.1):

Figure 3.1 MiniPLC2/05

Processor (cat. no. 1772LS)

RUN

P R O C

FAULT

MEMORY

STORE

AB

INTFC

3-2

MINI PLC2/05

W/O Power Supply

10663I

Chapter 3

Hardware

Processor

Status Indicator

PROC RUN/FAULT: This red/green LED keeps you informed of the processor’s operating conditions.

Table 3.A

Indication

Status

Indicator

PROC RUN/FAULT Green

P/S ACTIVE Green

If the

color is

Blinking Green

Red

Off

MEMORY STORE (Switch)

Purpose: Enables you to backup or copy the program into the optional EEPROM Memory Module.

Then the Indication represents

The processor module is in the run mode and will begin operation. The EEPROM memory module (if present) is being programmed. There is a fault. Recycle power to reset the processor module. Either program mode of operation, run time error, memory error or a program error.

AC and DC is all right. There has been a power supply fault, overcurrent condition, improper input voltage or the module has been turned off.

Hardware: An optional EEPROM Memory Module (cat. no. 1772-MJ) can be installed in the module.

INTFC

(Interface socket)

Purpose: The 15 pin socket, labeled INTFC, provides communication between the processor and the programming terminal (1770-T3 or 1784-T50), the 1770-RG report generation module, the 1770-T11 hand held terminal, the 1772-KG interface module or 1771-KA communications interface module.

Processor Module and: Through: Catalog Number:

Industrial Terminal (cat. no. 1770T3) PLC2 Program Panel

Interconnect Cable

Industrial Terminal (cat. no. 1784T50) PLC2 Program Panel

Interconnect Cable

Data Highway Communication Modules Data Highway/Processor Cables 1771CN, CO, or CR

PLC2 Family Report Generation Module (cat. no. 1770RG)

PLC2 Program Panel Interconnect Cable

1772TC

1772TC or 1784CP2

1772TC (with external ground wire only)

The 1784-T50 also requires PLC-2 6200 programming software (cat. nos. 6201-PLC2, 6203-PLC2, 6211-PLC2, or 6213-PLC2).

Function: Provides interface to the above devices.

3-3

Chapter 3

Hardware

MiniPLC2/05 Processor (cat. no. 1772LSP)

The Mini-PLC-2/05 Processor (cat. no. 1772-LSP) contains all the hardware features of the LS processor and in addition contains the following (Figure 3.2):

Figure 3.2 MiniPLC2/05

RUN

P R O

P/S

FAULT

ACTIVE

MEMORY

STORE

P/S

PARALLEL

AB

INTFC

POWER

OFF

I.0A 125V

SLOW BLOW

120V

AC L1

GND

MINI PLC2/05

W Power Supply

Processor with Power Supply (cat. no. 1772LSP)

10717I

3-4

Processor

Status Indicator

P/S ACTIVE: This green LED keeps you informed of the power supply section’s operating conditions (table 3.A).

P/S PARALLEL (socket)

Purpose: Enables paralleling connections between these two sockets on two power supply modules.

POWER (switch)

Purpose: This is on/off toggle switch lets you provide power to your processor.

If the switch is: Then you are:

On Supplying power to your processor module.

Off Not supplying power to your processor module.

Chapter 3

Hardware

Fuse

Purpose: Guards against overcurrent conditions on the input line.

Sizes: 1.0 amp fuse for 120V AC operations

Terminal Strip

Purpose: To provide wire connections for the processor.

Hardware: Terminals L1, N and GND label the AC input connections.

Switch

Assembly on the I/O Chassis

Purpose: Determines processor response to memory protect and power-up sequence.

Location: Left side of the I/O chassis backplane.

Settings:

If Then

Switch 8 is on Memory protection is on. Memory above 2008 cannot be changed by

the programmer.

Switch 8 is off Memory protection is disabled. memory can be changed by the

programmer. Memory can be changed when the processor module is in the program mode.

Switch 6 is off Contents of the EEPROM is always transferred to the CMOS RAM at

powerup.

Switch 6 is on

and

Switch 7 is off

Switch 6 is on

and

Switch 7 is on

The settings for Switch 1- Switch 5 do not matter.

Memory transfer does not occur and the module gives a fault indication.

If the CMOS RAM passes its checksum on powerup, the contents of the EEPROM transfer to the CMOS RAM.

Important: Series A/Revision A of the 1770-T3 industrial terminal is not compatible with memory protect feature.

ATTENTION: Use a ball point pen to set each switch. Do not use a lead pencil because the tip can break off and jam the switch.

3-5

Chapter 3

Hardware

Optional Features

Battery

Backup

Purpose: Provides battery backup power for the processor’s memory.

Hardware: Size AA, 3.6V Lithium Battery, 1.785 amp hr, 0 to 70

Function: In order for you to retain processor memory after loss of power, the processor contains an AA size lithium battery. A removeable holder located at the rear of the processor module houses your battery. This battery supports stored memory for up to two years. We recommend documenting the start-up date of your processor. Put the date on the label at the side of the processor.

Industrial

erminal

Purpose: You need the Industrial Terminal System (cat. no. 1770-T3) or an Industrial Terminal (cat. no. 1784-T50) with 6200 programming software (6201-, 6203-, 6211-, 6213-PLC2) to program the processor and access the processor modes of operation (Figure 3.3).

Figure 3.3 Industrial

erminal System

3-6

10697I

Function: With your industrial terminal you can:

enter edit test troubleshoot

your program.

Chapter 3

Hardware

Installation

Before you start to program your processor make sure all of your peripheral equipment is installed properly. Follow these basic instructions to install the industrial terminal to the processor. Refer to Figure 3.4 when following these instructions.

Figure 3.4

Industrial

Industrial Terminal

(rear view)

Channel A PLC2 Family

erminal Installation

Program Panel Interconnect Cable

MiniPLC2/05

Interface

1. Plug the ac power cord of the industrial terminal to the incoming

ac power source.

2. Connect one end of the PLC-2 Program Panel Interconnect Cable

(cat. no. 1772-TC) to CHANNEL A at the rear of the industrial terminal.

10249

3. Connect the other end of the cable to the socket labeled INTFC at the

front of the processor.

3-7

Chapter 3

Hardware

MODE

SELECT

DATA

INIT

EXPAND

ADDR

SBR

T.END

4. Place the PLC-2 Family Keytop Overlay (cat. no. 1770-KCB)

(Figure 3.5) onto the keyboard.

Figure 3.5

Family Keytop Overlay

PLC2

(RET)

(JSR)

LBL

(JMP)

EAF

(SCT)

CONVERT

FILE SEQ

SHIFT

REG

BLOCK

XFER

RECORD

DISPLAY INSERT

HELP

MEMORY

SHIFT

RUNG SEARCH

CLEAR

CANCEL

COMMAND

REMOVE

( )

( P )

( X ) [ = ] [ L ] (CTD) (TOF) ( U )

( - ) [ < ] [ B ] (CTR) (RTO) (MCR)

[ G ] [ I ] (CTU) (TON) ( L )

( + ) (PUT) (IOT) (ZCL) (RTR) ( )

FOR

USE WITH PLC2 F

AMILY CAT

. NO. 1770 KCB

123

FORCE

 1982 ALLENBRADLEY 97534302

Table 3.B Definitions

This key: Does this: This key: Does this: This key: Does this:

top row of keys

MODE

SELECT

select terminal mode

DATA

INIT

of Keys

enter data into a file

EXPAND

ADDR

enter expanded address

FORCE

OFF

10291–I

3-8

SBR

T.END

EAF

(SCT)

SEQ

SHIFT routine

enter temporary

– enter sub

SHIFT – enter EAF, expanded not applicable

math to MiniPLC-2/05

enter sequencer

(RET)

(JSR)

CONVERT

SHIFT

REG

SHIFT – enter return

enter jump to sub-

not applicable to MiniPLC2/05

LBL

(JMP)

FILE

BLOCK

XFER

SHIFT – enter label

enter

jump to jump

enter file instruction

enter block transfer

second row of keys

enter new data

RECORD

RUNG

specify rung

Chapter 3

Hardware

specify search

( )

(CTU)

third row of keys

DISPLAY

( X )

(CTD)

enter 3digit divide

enter up counter

enter branch end

SHIFT – enter C enter 9

display specified data

enter 3digit multiply

enter down counter

enter branch start

[ G ]

(TON)

INSERT

[ = ]

(TOF)

enter get

enter timer ondelay

SHIFT – enter A enter 7

insert the next specified item

enter equal

enter timer offdelay

SHIFT – enter D enter 4

[ I ]

( L )

REMOVE

[ L ]

( U )

enter immediate input

enter output latch

SHIFT – enter B enter 8

remove the next specified item

enter limit test

enter output unlatch

SHIFT – enter E enter 5

fourth row of keys

HELP

[ B ]

(MCR)

SHIFT – enter F enter 6

display help directory

SHIFT

– move cur

sor down

CLEAR

MEMORY

( - )

clear processor memory

enter 3digit subtract

move cursor down

enter get byte

(CTR)

enter master control reset enter examine off

enter a 2

enter counter reset

enter a 3

[ < ]

(RTO)

SHIFT sor up

move cursor up

– move cur

enter less than

enter retentive timer ondelay

enter a 1

3-9

Chapter 3

Hardware

fifth row of keys

SHIFT

(IOT)

access function on top half of keys that support two functions

SHIFT

– move cur sor right move cursor right

enter immediate output

CANCEL

COMMAND

( + )

(ZCL)

end current function without saving

enter 3digit add

enter zone control last state

(PUT)

(RTR)

SHIFT – move cur sor left

move

cursor left

enter put

enter retentive timer reset

( )

enter output energize enter examine on

enter a 0

FORCE

OFF

specify force off

FORCE

specify force off

5. Turn the power switch on the front of the industrial terminal to the

ON position.

6. After a short while the following display will appear.

DIAGNOSTICS PASSED

MODE SELECTION

KEYBOARD MODULE 1770-FDC SERIES B/E

FOR USE WITH THE FOLLOWING PROCESSORS:

PLC MINI-PLC-2, PLC-2 MINI-PLC-2/15 PLC-2/20 (LP1) PLC-2/20 (LP2) PLC-2/30

10 = PLC

= PLC-211

12 = ALPHANUMERIC

INSERT

KEYTOP OVERLAY:MODE:

1770-KBA 1770-KCB

1770-KAA

3-10

SELECT DESIRED MODE?

11595

Select your desired processor mode by pressing 11 on the 1770-T3 terminal.

7. After initialization has been completed, select the processor mode of

operation using the keystrokes below:

Chapter 3

Hardware

Run/Program [SEARCH] 590 Remote test [SEARCH] 591 Remote Program [SEARCH] 592

ATTENTION: Use only Allen-Bradley authorized programming devices to program Allen-Bradley programmable controllers. Using unauthorized programming devices may result in unexpected operation, possibly causing equipment damage and/or injury to personnel.

Important: When power is re-applied following a power failure and if switch 6 is on, the processor returns to the last programmed mode of operation.

If you are not familiar with each mode of operation, here is the way we define each term:

Run/Program - This is the normal mode of operation where the program controls your outputs. you can edit your program and make on-lien data changes when you are in this operational mode.

Remote Test - The program is executed, the inputs are scanned, the outputs are disabled. The selectable timed interrupts are executed.

Remote Program - The processor stops scanning and executing its stored program and waits for commands from the programmer. If you have an optional EEPROM memory module, you must be in the remote program mode when duplicating RAM memory contents to the EEPROM memory module. Refer to Memory Module Product Data (publication 1771-936) for operational details on memory transfer.

Industrial

erminal Keyboard

Function: The detachable keyboard houses PROM memory, a sealed touchpad, and a keytop overlay.

There are three keytop overlays:

PLC-2 Family - for use with any PLC-2 family processor. PLC - for use with any PLC family processor. Alphanumeric - for alphanumeric characters and graphic

characters generation.

Key Symbols - There are no numbered keys greater than 9. To display numbers which are greater than 9 press the individual keys. For example:

3-11

Chapter 3

Hardware

To display: 1011 Press individually: 1011

Some keys have two symbols occupying one key (Figure 3.5). To display the top section of each key use your shift key before the desired symbol. For example:

Press 7: To display 7 Press[SHIFT] A: To display A

Data Monitor Functions - You can display on a CRT and print directly to a data terminal - binary, hexadecimal, and ASCII data monitor functions by performing the keystrokes in table 16.B.

Chapter Summary

Paralleling

Cable

Purpose: using the 1772-CT parallel cable, you can parallel with 1772-P3, 1771-P4 power supply for start up.

EEPROM Memory Module

Purpose: Provides you with a 3K non-volatile backup.

Hardware: EEPROM Memory Module (cat. 1772-MJ)

Function: After you’ve entered the application program into the processor module’s CMOS RAM memory, the program can be copied into the EEPROM.

So far, we’ve briefly described the hardware associated with your Mini-PLC-2/05 processors. The next chapter explains memory and how the processor stores and manipulates data. Read the next chapter carefully. It is a fundamental concept that you must master before continuing.

3-12

Memory Organization

Chapter

Chapter Objectives

Introduction

In this chapter, you will read about:

hardware and its relationship to your program memory and its components

This chapter provides detailed concepts of the memory’s organization and its structure. Understanding these concepts aids you in programming your processor.

Before we explain memory organization and its structure, read the following definitions:

Bit - the smallest unit of information that memory is capable of retaining Byte - a group of 8 consecutive bits (00-07 Word - a group of 16 consecutive bits (00-17

Hardware and Your Program

Figure 4.1 and the following chart represents how the hardware of your processor relates to the input and output image tables. Understanding the two figures help you understand programming.

or 10-1708)

)

41

Chapter 4

Memory Organization

Figure 4.1

Address Equals Memory Bits

Word

Concept Example

Hardware Terminology Hardware Terminology

Input (1) or Output (0)

Rack No. (Always 1)

Module Group No.

(0-7)

Terminal No. (00-07, 10-17)

X X/XXX

Word Address

I/O terminal bit

module group word

module slot byte

one rack eight words

if the terminal has voltage (on state) a specific bit is on, which is a 1 in memory

if the terminal has no voltage (off state) a specific bit is off, which is a 0 in memory

Bit Address

Data Table Terminology

Hardware vs Your Program

0 0/121

Word Address

Data Table Terminology

Output: 0

Rack No.: 1

Module Group No.: 0

Terminal No.: 12

Bit Address

10248

42

To calculate the input and output image tables’ areas and how these values compare with the hardware of your processor.

Remember: 1 rack = 8 words You can only have one rack in this system.

Therefore: 8 words/rack x 16 bits - 128 I/O Conclusion: The combined amount of usable bits in the input image

table and/or the output image table is 128 I/O.

Chapter 4

Memory Organization

Memory Areas

Memory is divided into three major sections: data table, user program and a message storage area. The areas store input status, output status, your program instructions and messages.

We describe these areas in detail so you can gain programming flexibility using your processor.

Data Table

The first part of memory is the data table (Figure 4.2). The processors are factory configured for 128 words. Figure 4.3 shows memory structure with a factory configured data table. The specific concepts throughout this publication refer to a factory configured data table.

Figure 4.2 Memory

Structure

Data Table

Main Program

Subroutine

Message Storage Area

User Program

10151I

43

Chapter 4

Memory Organization

Figure 4.3

Table Organization, Factory Configured

Data

Total

Decimal

Words

Decimal

Words

Per

Area

Processor Work Area

No. 1

Output

Image Table

Bit/Word Storage

Reserved

Timer/Counter

Accumulated Values (AC)

(or Bit/Word Storage)

Processor Work Area

No. 2

Input

Image Table

Word

Address

000

007 010

017 020

026 027 030

077 100

Bit

Address

17 00

FactoryConfigured Data Table

Maximum Size of Data Table

107

110

Bit/Word Storage

Timer/Counter

Preset Values (PR)

128

(or Bit/Word Storage)

Expanded Data Table

2944

2816

3072 128

May not be used for accumulated values.

Not available for bit/word storage. Bits in this word are used by the processor.

Unused timer/counter memory words can reduce data table size and increase user program area.

May not be used for preset values. Do not use word 127 for block transfer data storage.

and/or User Program

User Program

Can be decreased to 48 words.6

44

117

120

127

130

177

200

5577 17

End of Memory

10148I

Chapter 4

Memory Organization

The data table area is a major part of memory. It is divided into six sections which includes the input and output image tables. (These two areas were described in chapter 2). The processor controls and utilizes words stored in the data table. The input devices coupled with the control logic from your program determines the status of the output devices. Input devices are limit switches, pushbutton switches, pressure switches, etc. Output devices are solenoids, motor starters, alarms, etc. Transfer of input data from input devices and the transfer of output data to output devices occur during I/O scan. If the status of the output instruction changes in the program then the on or off status of the output devices update during the I/O scan to reflect the change.

To use the data table, you must understand the following:

The processor initially reserves the first 128 words in the memory for the

data table.

You can decrease the data table size to 48 words in two word increments.

You can increase the data table size to 256 words in two word increments.

Then you can increase the data table size in blocks of 128 words.

When the data table is set to 256 words, you can program up to 104

timer/counter instructions.

You can change the data size from 48 words to 2,944 words using the

1770-T3 terminal.

Data Table Expansion

Using the 1770-T3 industrial terminal, you can adjust the data table size to be anywhere from 48 words to 2944 words. Expanding the data table provides additional timers/counters and space for files (see chapter 8 for timers/counters and chapter 10 for file information), but it also proportionally reduces the program storage and memory areas.

Expansion is in increments of two words until a table of 256 is reached and then in increments of 128 words.

Important: When using the data table expansion capability, allow sufficient room for both data table and user program.

45

Chapter 4

Memory Organization

To expand your data table do this:

The

word SEARCH appears in the lower left hand corner of

the screen.

DAT

A TABLE CONFIGURA

TION

NUMBER OF 128WORD D.T NUMBER OF INPUT/OUTPUT RACKS NUMBER OF T/C (if applicable) DAT

A T

ABLE SIZE

. BLOCKS

01 2 40 128

The following chart helps you adjust the data table size for your processor:

Enter Data Table Size

01 128 02 256 03 384 04 512 05 640 06 768 07 896 08 1024 09 1152 10 1280 11 1408 12 1536 13 1664 14 1792 15 1920 16 2048 17 2176 18 2304 19 2432 20 2560 21 2688 22 2816 23 2944

46

After you adjust the data table, press [CANCEL COMMAND]. Important: Other industrial terminal commands are summarized in

appendix C.

Chapter 4

Memory Organization

Data Table Areas

The following areas make up the data table. They are:

processor work area no. 1 output image table bit/word storage (020-027) timer/counter accumulated values and internal storage processor work area no. 2 input image table bit/word storage (120-127) timer/counter preset values and internal storage

Chapter 1 describes the input and output image tables. The following sections describe the remaining areas.

Processor Work Areas

Purpose: The processor uses these 16 words for its internal control functions.

Description: There are two processor work areas. They are located at addresses 000-007 and 100-107. You cannot access these data table words. Their word addresses are not available for addressing.

Important: The term address is defined in chapter 6. Remember, all addresses are in octal values.

Accumulated Values and Internal Storage

Purpose: Stores accumulated values of timer or counter instructions. This area also stores data by words and/or bits from your program instructions (addresses 030-077).

Description: Each timer or counter instruction uses two words of data table. one word is stored in the accumulated value area, the other is the preset value area. When the accumulated value equals the preset value (AC=PR), a status bit is set and can be examined to turn on or off an output device.

Preset Values and Internal Storage

Purpose: Stores preset values (PR) of timer or counter instructions. This area also stores data by words and/or bits from your program (addresses 130-177).

Description: The preset value is the number of timed intervals or events to be counted. The preset value is 100 octal words above the accumulated word. Therefore, a timer/counter having an address of 030 automatically has its preset value stored at address 130.

47

Chapter 4

Memory Organization

User Program

The second major part of memory is the user program (Figure 4.2). It is divided into two areas:

main ladder diagram program subroutine area

The user program area begins at the end of the data table.

Main Program

Purpose: The program is a group of ladder diagram and functional block instruction used to control an application.

Description: A program is a list of instructions that guides the processor. These instructions can examine or change the status of bits in the memory of the processor. The status of these bits determines the operation of output devices.

The program specifies the things you want done in your application and the conditions that must be met before those things are done. For example, if you want a solenoid energized when a limit switch is closed, you would specify:

Condition: If limit switch is closed Action: Energize solenoid

Programming logic differs from relay logic in an important way. Programming logic is only concerned with whether or not conditions have been met. These conditions may be open or closed input or output devices. We must have a continuous or unbroken path of true logic conditions for an action to be taken. The number of conditions is not important. There can be none, one, or many conditions preceding an output action.

When the path of conditions is continuous, we say that the rung is true. When the path of conditions is not continuous, we say the rung is false.

Subroutine Area

Purpose: Used to jump to a defined ladder diagram area. This allows you to perform ladder diagram subroutines.

Description: The subroutine area is between the main program and the message store areas. This area acts as the end of program statement for the main program. It allows storage of small programs that are to be accessed periodically. Subroutine areas are not scanned unless you program the processor to jump to this area.

48

A maximum of eight subroutines can be programmed in the subroutine area. Each subroutine begins with a label instruction and (when you want to exit to your main program) ends with a return instruction.

Chapter 4

Memory Organization

Message Storage Area

The third major part of memory is the message storage area (Figure 4.2). You can print out messages in hard copy form. You can store up to 70 messages using the 1770-T3 industrial terminal, or 198 messages using the 1770- T3 terminal with the 1770-RG module.

Message storage follows the end statement of your program and is limited by the number of unused words remaining in memory. Each word stores two message characters. A character is any alpha or numerical figure (this includes blank spaces).

Messages are written to display current data table information such as the number of parts rejected in a production run for a particular time period. you can write your program to display messages when a pushbutton switch is activated.

Chapter Summary

Address 027 controls messages 1-6. You designate control words which control your messages in groups of 8. Your control word must be arranged in consecutive order.

Report generation (see chapter 17) is a function of your message control words. Reserve bit addresses 02710 thru 02717 for this automatic report generation function to determine status of this function. These bit addresses should not be used for any other functions if you want to achieve maximum flexibility within your program.

We described detailed concepts of memory organization and its structure. The next chapter explains how the processor scans the program.

49

Scan Theory

Chapter

Chapter Objectives

Scan Function

In this chapter you will read about:

scan function scan time

The processor controls the status of output devices or instructions in accordance with program logic. Every instruction in your program requires execution time. These times vary greatly depending upon the instruction, the amount of data to be operated on, and whether the instruction is true or false.

As a review from chapter 1, there are two types of scans (Figure 5.1):

I/O scan (775µs without forcing: 1 ms with forcing) Program scan (15ms/K of user memory)

51

Chapter 5

Scan Theory

Figure 5.1

Sequence

Scan

I/O

Scan

Program

Scan

Output Image Table

Input

Terminals

Output

Terminals

Copy output image table status into output terminal circuits.

Input Image Table

Copy input terminal status into input image table

Program Statement

52

Execute each program rung in sequence, writing into bits in the data table, including the output image table.

11597

Chapter 5

Scan Theory

On power-up, the processor begins the scan sequence with the I/O scan. Data from output image table is written to the output modules. Data from the input modules is read into the input image table.

Next, the processor scans the program statement by statement:

1. For each condition, the processor checks, or “reads,” the image table to see

if the condition has been met.

2. If the set of conditions has been met, the processor writes a one into the bit

location in the output image table corresponding to the output terminal to be energized. On the other hand, if the set of conditions has not been met, the processor writes a zero into that bit location, indicating that the output terminal should not be energized.

Important: When your processor is in the remote test mode, all outputs are held off. When your processor is in the run/program mode, all outputs are controlled by the user program.

Average Scan Time

Average scan time is the average amount of time it takes the processor to monitor and update input and outputs, and to execute instructions in the program. The scan is performed serially; first the I/O image table is updated, (other parts of the data table are not scanned), then the user program is scanned.

There are two ways to measure average scan time:

Append the rungs in Figure 5.2 to your program.

Figure 5.2 Average

031

Scan T

ime

Store

032

000

010

Rung 1

Rung 2

Rung 3

Rung 4

Rung 5

Rung 6

031

CTU

PR 999 AC 000

031

CTU

PR 999 AC 000

032

RTO

0.1 PR 999 AC 000

Store

000 .

000

032

RTR

PR 999 AC 000

032

RTR

PR 999 AC 000

53

Chapter 5

Scan Theory

Add the execution values for each instruction by using Table 5.A. The sum of

these values added to the I/O scan time is the average scan time.

Table 5.A Approximate

Instruction Name Symbol

Examine on, Examine off Output energize Output latch (L) 17 13 Output unlatch (U) 17 13

Get [G] 28  Put (PUT) 26 14

Equal (=) 23 11 Less than (<) 25 13

Get byte |B| 16  Limit test |L| 24 11

Counter reset (CTR) 20 14 Retentive timer reset (RTR) 20 14

Timer ondelay (TON) 75 47 Retentive timer ondelay (RTO) 78 48 Timer offdelay (TOF) 82 60

Up counter (CTU) 70 55 Down counter (CTD) 75 60

3 Digit Math

Add (+) 48 15 Subtract () 80 19 Multiply (x)(x) 615 60 Divide

Add to any of the above when its address is 4008 or greater

Expanded Math

Add EAF 01 400500 40 Subtract EAF 02 400500 40 Multiply EAF 03 8002250 40 Divide EAF 04 5003250 40 Square root EAF 05 1850 40 BCD to binary EAF 13 500 40 Binary to BCD EAF 14 500 40

Master control reset (MCR) 16 16 Zone control last state

Branch start 16 16 Branch end 18 18 End, temporary end T.END 27 27 Subroutine area SBR 27 27

Immediate input update

Immediate output update (IOT) 70(with forcing on 80) 17

Execution T

ime Per Scan (in average microseconds)

Instruction

True

| |,| / |

( )

( ÷ )( ÷ )

(ZCL) 22(no skip) 20+(13 per word skipped)

[ I ]

45 (with forcing on 55) 

14 11 16 16

875 60

27 27

Instruction

False

54

Chapter 5

Scan Theory

Instruction Name

Label LBL 34  Return (RET) 30 15 Jump to subroutine (JSR) 100 15 Jump (JMP) 55 15

Block transfer read BLOCK

XFER 1

Block transfer write BLOCK

XFER 0

Sequencer load SEQ 2 390(80/extra word) 105

Sequencer input SEQ 1 420(90/extra word) 55

Sequencer output SEQ 0 470(90/extra word) 110

Filetoword move FILE 12 250 45 Wordtofile move FILE 11 250 45 Filetofile move FILE 10440 (+10/word

transferred)

When a rung that contains a ZCL instruction is false, the execution time of each instruction between the start fence and

end fence is 17 microseconds per word.

Instruction

TrueSymbol

80 75

200

Instruction

False

Here is an explanation of the rungs in Figure 5.2: Rung 1 - The count increments its accumulated value each time this rung

is true.

Chapter Summary

Rung 2 - This rung enables the counter to increment on the next scan. If we did not have this rung, the counter would always be true and it would not increment. Remember: Counters increment only on false to true transitions.

Rung 3 - The timer times in tenths of seconds when we are counting. This value is displayed on the industrial terminal screen.

Rung 4 - The average scan time is displayed beneath store 2 and store 3 in milliseconds.

Important: Refer to three digit math in chapter 10. Rung 5 - The counter overflow bit is re-setting the timer. Rung 6 - The counter overflow bit is resetting the counter.

We described scan sequence and a method to measure average scan time. The next chapter explains some of the instructions you use in a program.

55

Relaytype Instructions

Chapter

Chapter Objectives

Programming Logic

This chapter describes:

relay-type instructions how to define conditions before an action takes place

A program is a list of instructions that the processor executes. These instructions can examine or change the status of bits in the data table of the processor. The status of these bits can determine the operation of other instructions.

The program you specifies the order of things you want done in your application and the conditions that must be met before those things are done. For example, if you want a solenoid energized when a limit switch is closed, you specify:

Condition: if limit switch is closed Action: energize solenoid

Programming logic differs from relay logic in an important way. Programming logic is only concerned with whether or not conditions have been met. These conditions may be open or closed input or output devices. We must have a continuous or unbroken path or true logic conditions for an action to be taken. The number of conditions is not important. There can be none, one, or many conditions preceding an output action.

Perhaps an example might make this clearer:

True

False

Here, a series of conditions (C2, C2, C3) must be true before action A is performed.

True

61

Chapter 6

Relay-type Instructions

C1 = Input switch 1. When the switch is on, this condition is true. This switch turns on a conveyer belt.

C2 = Input sensor 1. When the sensor is off, this condition is true. This sensor detects if the temperature in the factory is below 40

C3 = Input sensor 2. When the sensor is on, this condition is true. This sensor detects the presence of a part of the conveyer belt.

A = The part will be drilled. = The path of conditions is continuous, that is, all conditions are true.

When C1, C2, and C3 are true, then a continuous path is made to a particular action. In this case, the continuous path causes the part to be drilled. When the path of conditions is continuous, we say that the rung is true. When the path of conditions is not continuous, we say the rung is false.

True

False

True

Here the path of conditions is not continuous because condition 2 is false. Therefore, the action A is not performed. We say the rung is false.

62

Set vs. Reset

As a review, if the device goes on, then we say the corresponding bit in data table is set to a 1. If the device goes off, we say the corresponding bit in data table is reset to a 0. (From this point on, set means the on-condition or 1. Reset means the off-condition or 0.)

If the device is: Then a bit in memory is

on set

off reset

Addresses

The processor scans the status of inputs and controls output devices. It does not go to the input or output terminals to see if outputs are on or off. Rather, it checks the status of the input and output devices by scanning corresponding bits in the input and output image area of the data table. The processor uses addresses to refer to words and bits in the data table.

Chapter 6

Relay-type Instructions

Each input and output bit has a five-digit address. Reading from left to right:

the first number denotes the type of I/O module:

- 0 output

- 1 input

the second number denotes an I/O chassis and it always is a 1. the third number denotes a module group. This number will range from 0-7. the fourth and fifth numbers denote a terminal designation:

- 00-07 left slot of the module group

- 10-17 right slot of the module group

Important: Remember a Mini-PLC-2/05 processor can use only one rack. Important: For addressing purposes, I/O modules in a given I/O rack are

organized into “module groups.” A module group is a pair of adjacent I/O modules. Thus, the module group number of an individual I/O module depends only on the I/O slot the module occupies. It is important to note that the first module group in any I/O chassis is always module group 0.

Programming Instructions

You can use seven programming instructions to write a program. These instructions are divided into three categories: bit examining, bit controlling, and branch instructions.

Bit Examining

Examine On and Examine Off

Purpose: The Examine On -] [- and Examine Off -]/[- instructions tell the processor to examine a bit at a specified data table location

112

Bit Examining Examine On

112

Bit Examining Examine Off

Determines the bit condition. The bit condition becomes:

012

True - Examine On detects a bit in the data table that is set. True - Examine Off detects a bit in the data table that is reset. False - Examine On detects a bit in the data table that is reset. False - Examine Off detects a bit in the data table that is set.

63

Chapter 6

Relay-type Instructions

Keystrokes: Enter an Examine On or Examine Off instruction by performing the following steps.

1. Press either -] [- or -]/[- as required.

2. Enter <address>. Removing the Examine On or Examine Off Instruction

You remove an Examine On or a Examine Off instruction by performing the following steps.

1. Position the cursor over the Examine On or Examine Off instruction you

want to remove.

2. Press [REMOVE] -] [- or -]/[-. Editing a Partially Completed or a Completed Rung

You edit an Examine On or Examine Off by performing the following steps.

If you are editing a completed rung, proceed to step 1. If you are editing a partially completed rung, enter the next instruction and proceed to step 1.

1. Position the cursor over the Examine On or Examine Off instruction you

want to edit.

2. Press either -] [- or -]/[- or any other appropriate instruction type key.

3. Enter <address>.

Bit Controlling

Output Energize

Purpose: This Output Energize instruction tells the processor to set or reset a specified data table bit.

112

Controls a specific bit based on the rung condition. When its rung conditions are:

012

Bit Controlling

Output Energize

64

True - Output Energize sets a specified bit. False - Output Energize resets a specified bit.

Chapter 6

Relay-type Instructions

Keystrokes: You enter an Output Energize instruction by performing the following steps.

1. Press -( )-.

2. Enter <address>. Removing an Output Energize Instruction

The only way you remove an Output Energize instructions is to remove the entire rung. See chapter 16.

Editing in a Completed Rung

You edit the Output Energize instruction by performing the following steps. However, you cannot remove an output instruction.

1. Position the cursor over the Output Energize instruction you want

to change.

2. Press -( )- or any other appropriate output instruction type key.

3. Enter <address>. Output Latch/Unlatch

Purpose: The Output Latch -(L)- instruction tells the processor to latch and set a specified data table bit. It is usually paired with an unlatch instruction.

113

010

Bit Controlling

Output Latch

The Output Unlatch -(U)- instruction tells the processor to unlatch and reset a specific data table bit. It is usually paired with a latch instruction.

113

010

Bit Controlling

Output Unlatch

Important: The conditions for the Output Unlatch instruction must be different than the conditions that precede the Output Latch instruction.

These are retentive instructions. Retentive means that when the rung condition goes false, the latched bit remains set and the unlatched bit remains reset until changed by the program.

65

Chapter 6

Relay-type Instructions

These instructions control a specific bit based on the rung condition. When its rung conditions are:

True - Output Latch sets a specified bit. True - Output Unlatch resets a specified bit. False - No action is taken.

Keystrokes: You enter an Output Latch or Unlatch instruction by performing the following steps.

1. Press either -(L)- or -(U)- as required.

2. Enter <address>. Important: You can initially condition the latch or unlatch instruction to on or

off by pressing 1 or 0, respectively.

Editing in a Completed Rung

You edit an Output Latch or Unlatch instruction by performing the following steps.

1. Position the cursor over the Output Latch or Unlatch instruction you want

to change.

2. Press either -(L)- or -(U)- or any other output instruction type as required.

3. Enter <address>. Important: If power is lost, all latch bits remain in their last state. When power

is restored, all outputs connected to latch bits are energized immediately.

Branching Instructions

Use branching instructions when you want several parallel sets of conditions to make an output action possible. A program with branching says, “If this set of conditions is true, or if that set of conditions is true, perform the following action.” Branching allows two or more paths to reach the same output destination.

False

66

C1 A

True

Chapter 6

Relay-type Instructions

Here two conditions are parallel. As long as one of the conditions (C1 or C2) is true, a continuous path to the action exists. Therefore, the action is performed.

True

C1 A

True

False

True

Here are two sets of parallel conditions. If either set of conditions are true, the action is performed.

010

110

010

This illustration shows a program rung with branching, as it would appear by the 1770-T3 terminal display. You create a branch by using two different branch instructions. These are the branch start and branch end instructions.

Branch Start/End

Purpose: A Branch Start instruction begins each parallel logic branch of a rung. It allows more than one combination of input conditions to energize an output device.

A Branch End instruction completes a set of parallel branches. Keystrokes: You enter a Branch Start or Branch End instruction by performing

the following steps

1. Press either [

] or [ ].

Important: You must begin each rung of parallel conditions with a Branch Start instruction.

67

Chapter 6

Relay-type Instructions

Removing a Branch Start or Branch End Instruction

You remove either a Branch Start or Branch End instruction or change an instruction type by performing the following steps.

1. Position the cursor over either the Branch Start or Branch End instruction.

2. Press [REMOVE] [

] or [ ].

Inserting a Branch Instruction in a Completed Rung

You insert either a Branch Start or Branch End instruction or change an instruction type by performing the following steps.

1. Position the cursor over the instruction immediately preceding the position

you want to insert a Branch Start instruction.

2. Press [INSERT] [

Important: Once you press the Branch Start instruction, the statement BRANCH END OMITTED appears in the lower lefthand corner of the screen. It stays there until you enter a Branch End instruction.

3. Insert the conditioning instructions for this rung.

4. You must begin each set of parallel conditions or rung with a

Branch Start instruction.

Complete the set of parallel conditions by:

5. Press [INSERT] [

68

Important: Once you press the Branch End instruction, the statement BRANCH END OMITTED disappears.

Nesting

The following rung shows a nested branch.

110

110 110

110

010

Chapter 6

Relay-type Instructions

Creating nested branches is not possible because the branch end instruction completes a branch group. But the above rung shows a single branch group with two branch end instruction. Above, the examine on instruction with the address 11012 is actually a branch group within a branch group.

The following rung achieves the same result and avoids nested branching:

Chapter Summary

110

110 110

110

010

We showed you how enter and edit bit examining, bit controlling, and branching instructions. The next chapter shows you how to use program control instructions to update I/O ahead of their usual scan time.

69

Chapter

Program Control Instructions

Chapter Objectives

Introduction

This chapter describes these program control instructions:

output override immediate I/O update

Some applications need programming techniques designed to override a group of non-retentive outputs or update I/O ahead of the usual I/O scan time. The program control instructions satisfy this need.

The output override, or zone type instructions, operate similarly to a hardwired master control relay in that they affect a group of outputs in the user program. But these instructions are not a substitute for a hardwired master control relay, which provides emergency I/O power shutdown.

The following table illustrates specific instructions for these categories:

Output Override Immediate Update I/O

Master Control Reset Immediate Input Update

Zone Control Last State Immediate Output Update

Output Override Instructions

Master

Control Reset and Zone Control Last State

Purpose: A Master Control Reset (MCR) establishes a zone in the user program in which all non-retentive outputs are turned off simultaneously.

Important: Retentive instructions (-(U)-, -(L)-, -(RTO)-) should not be placed within an MCR zone, because the MCR zone maintains retentive instructions in the last active state when the start fence goes false.

A Zone Control Last State (ZCL) instruction allows control of one or a group of outputs in more than one manner in the same program. It establishes a zone in the user program which controls the same outputs, through separate rungs, at different times.

71

Chapter 7

Program Control Instructions

To override a group of output devices, you must use two MCR (Figure 7.1) or ZCL (Figure 7.2) instructions: one each to begin the zone and one each to end the zone. The start fence is always programmed with a set of input conditions. The end fence must be programmed unconditionally.

Figure 7.1

Control Reset

Master

010

01100012

MCR

010

01500017

016

02000021

02200023

025

024

026

Figure 7.2 Zone Control Reset

010

01100012

010

01500017

011

012

013

014

MCR

ZCL

010

011

72

016

02000021

02200023

025

024

026

012

013

014

ZCL

Chapter 7

Program Control Instructions

If the start fence becomes:

True - Each rung condition controls their output instruction. False - All output instructions within the zone are left in their last state. The

same outputs may now be controlled by another zone program. Only one zone may control a set outputs at one time.

Keystrokes: You enter an MCR or ZCL instruction by performing the following steps.

1. Press either -(MCR)- or -(ZCL)-. Editing in a Completed Rung

You edit these instructions by performing the following steps:

1. Position the cursor over the MCR or ZCL instruction you want to change.

Immediate I/O Update Instructions

2. Press either -(MCR)- or -(ZCL)- or any other appropriate instruction

type key.

3. Enter any parameters that may be required by a new instruction.

Immediate I/O update instructions interrupt the program scan to update I/O data before the normal I/O update sequence. Use these instructions where I/O modules interface with I/O devices that operate in a shorter time period than the processor scan.

Immediate Input/Immediate Output Update

Purpose: An Immediate Input Update instruction interrupts the program scan to update input image table with data from the corresponding module group. The image table is updated before the normal I/O scan and executed each program scan (Figure 7.3). This instruction is always considered logic true and execution takes place whether or not other rung conditions allow logic continuity.

73

Chapter 7

Program Control Instructions

Figure 7.3 Immediate

Examine Bits in Word 112 Here in Program

Input Instruction

I/O Scan

Program Scan

Immediate Input Instruction Interrupts Program Scan

Returns to Program Scan

Word 112

16 Bits from One Module Group Written into Input Image Table Word

Module Group (Input)

10151I

An Immediate Output Update instruction interrupts the program scan to update the module group with data from corresponding output image table word address (Figure 7.4). The image table is updated before the normal I/O scan and executed each program scan when the rung is true. It can be programmed unconditionally. This instruction immediately transfers output data from the selected 16-bit word in the output image table without waiting for the normal I/O scan.

74

Chapter 7

Program Control Instructions

Figure 7.4 Immediate

Control Bits of Word 014 Here in Program

Output Instruction

I/O Scan

Program Scan

Immediate Output Instruction Interrupts Program Scan

Returns to Program Scan

Word

Writes All 16 Bits from One Output Image Table Word to One Module Group

Module Group (Output)

10152I

Important: These instructions significantly impact program scan time. Use them only when absolutely necessary.

Keystrokes: You enter an Immediate Input or Immediate Output Update instruction by performing the following steps.

1. Press either -[I]- or -[IOT]-.

2. Enter <address>.

75

Chapter 7

Program Control Instructions

Removing an Immediate Output Update Instruction

The only way to remove an Immediate Output Update instruction is to remove the entire rung. See chapter 11.

Removing an Immediate Input Update Instruction

You remove an Immediate Input Update instruction by performing the following steps.

1. Position the cursor over the Immediate Input Update instruction you want

to remove.

2. Press [REMOVE]-[I]-. Editing a Partially Completed Rung or a Completed Rung

You edit an Immediate Input or Immediate Output Update instruction by performing the following steps.

Chapter Summary

If you are editing a completed rung, proceed to step 1. If you are editing a partially completed rung, enter the next instruction and proceed to step 1.

1. Position the cursor over the Immediate Input or Immediate Output Update

instruction you want to change.

2. Press -(I)-, -[IOT]-, or any other appropriate instruction type key.

3. Enter <address>.

We have shown you how to override a group of non-retentive outputs to update I/O ahead of their usual scan time. The next chapter shows you how to keep track of timed intervals or counted events according to the logic of your ladder diagram.

76

Timers and Counters

Chapter

Chapter Objectives

Introduction

This chapter describes two instructions that keep track of timed intervals or counted events:

timers counters

Timer and counter instructions are output instructions internal to the processor. They provide many of the capabilities available with timing relays and solid state timing/counting devices. Usually conditioned by examine instructions, timers and counters keep track of timed intervals or counted events according to the logic continuity of the rung. You can program up to 488 internal timers. The last valid timer address is 1677.

Each timer or counter instruction has two 3-digit values. Each value requires one word of data table memory. These 3-digit values are:

Accumulated Value (AC)

Storage: Begins at word address 030.

Function: Timers - number of elapsed timed intervals

Counters - number of counted events Both - upper 4 bits of accumulated word (14-17) are the status bits.

Timer Instructions

Preset Value (PR)

Storage: Always at address 100 words greater than its corresponding AC value.

Function: Denotes the number of timed intervals or events to be counted. When the accumulated value equals the preset value, AC = PR, a status bit is set and can be examined to turn an output device on or off.

A timer counts the elapsed time-base intervals and stores this count in the accumulated value word. All timers must be placed within the first eight data table blocks. Timer instructions have three time bases: 1.0 second, 0.1 second, or 0.01 second.

81

Chapter 8

Timers and Counters

Two bits in the accumulated value word are status bits:

Bit 15 is the timed bit. It is either set or reset when the timer has timed out.

The setting or resetting depends on the type of timer instruction used.

Bit 17 is the enable bit. It is set when rung conditions are true and is reset

when rung conditions are false.

There are four types of timer instructions available with the controller:

timer on-delay timer off-delay retentive timer on-delay retentive timer reset

We will look at these timers in detail.

Timer On/Timer Off Delay

Purpose: The Timer On and Timer Off Delay instructions can be used to turn a device on or off once an interval is timed out.

Timer On Delay

The Timer On Delay instruction is programmed as an output instruction.

010

When the timer on delay rung condition becomes:

True

Timer cycle begins. Timer increments its AC value. Bit 15 is set when AC=PR and the timer stops timing. Bit 17 is set.

False

030

TON

1.0 PR 150 AC 000

82

Accumulated value resets to 000. Bits 15 and 17 are reset.

Chapter 8

Timers and Counters

Timer Off Delay

The Timer Off Delay instruction is programmed as an output instruction.

010

030

TOF

1.0 PR 150 AC 000

When the timer off delay rung condition becomes:

True

Bit 15 is set. Bit 17 is set. Accumulated value resets to 000.

False

Timer cycle begins. Timer increments its AC value. Bit 15 resets when the AC=PR and the timer stops timing. Bit 17 is reset.

Keystrokes: You enter a Timer On or a Timer Off Delay instruction by performing the following steps.

1. Press either -(TON)- or -(TOF)-.

2. Enter <address>.

3. Enter <time base>.

4. Enter <preset value>. Editing in a Completed Rung

You edit the Timer On or Timer Off Delay instruction by performing the following steps.

1. Position the cursor over the Timer On or Timer Off Delay instruction you

want to change.

2. Press -(TON)-, -(TOF)-, or any other appropriate instruction type.

3. Enter <address>.

4. Enter <time base>.

5. Enter <preset value>.

83

Chapter 8

Timers and Counters

Retentive Timer On/Reset

Retentive Timer On

Purpose: The Retentive Timer On accumulates the amount of time that the preconditions of its rung are true. It controls one or more outputs (by means of other rungs) after the total accumulated time is equal to the preset time. Whenever the rung is false, the accumulated time is retained. If the outputs have been energized, they remain on. The accumulated time and energized outputs are retained if power is removed from the processor. A separate rung, containing a retentive timer reset instruction must be programmed in order to reset the accumulated time to zero and turn off the outputs.

010

When the rung condition becomes:

True

Timer begins counting time-base intervals. Bit 15 is set when AC=PR and the timer stops timing. Bit 17 is set.

False

Accumulated value is retained. Bit 15 - no action is taken. Bit 17 is reset.

Important: The RTO instruction retains its AC value when the:

Rung condition turns false. Processor changes to remote/program mode. Power outage occurs and memory backup is maintained.

030

RTO

1.0 PR 150 AC 000

84

Retentive Timer Reset

Purpose: The Retentive Timer Reset instruction resets the accumulated value and timed bit of the retentive timer to zero. This instruction is given the same word address as its corresponding RTO instruction. When the rung conditions go true, the RTR instruction resets the ac value and resets the status bits to zero.

010

030

RTR

PR 150 AC 000

Chapter 8

Timers and Counters

When the rung condition becomes:

True

RTR instruction resets the accumulated value of the RTO instruction. Bits 15 and 17 are reset.

False

No action is taken.

Keystrokes: You enter a Retentive Timer On or a Retentive Timer Reset instruction by performing the following steps.

1. Press -(RTO)- or -(RTR)-.

2. Enter <address>.

Perform the following step for a Retentive Timer instruction only.

3. Enter <time base>.

4. Enter <preset value>. Editing in a Completed Rung

You edit a Retentive Timer On or a Retentive Timer Reset instruction by performing the following steps.

1. Position the cursor over the Retentive Timer or Retentive Timer Reset you

are going to change.

2. Press -(RTO)-, -(RTR)-, or any other appropriate instruction type key.

3. Enter <address>. Important: Do not perform steps 4 and 5 for a Retentive Timer

Reset instruction.

4. Enter <time base> if appropriate.

5. Enter <preset value>.

Counter Instructions

A counter counts the number of events that occur and stores this count in its accumulated value word. Counters can be located anywhere in the data table. The last valid counter address is 5477 (in a fully expanded data table). An event is defined as a false-to-true transition. Counter instructions have no time base.

85

Chapter 8

Timers and Counters

The upper four bits in the accumulated value (AC) word are status bits:

Bit 14 - Overflow/underflow bit. It is set when the AC value of the CTU instruction exceeds 999 or when the AC value of the CTD instruction falls below 000.

Bit 15 - Count complete bit. it is set when the AC value >

PR value.

Bit 16 - Enable bit for CTD instruction. It is set when the rung condition is true.

Bit 17 - Enable bit for CTU instruction. It is set when the rung condition is true.

There are three types of counter instructions available with the controller:

up counter down counter counter reset

Up Counter

Purpose: An Up Counter instruction increments its accumulated value for each false-to-true transition of the rung condition.

010

030

CTU

PR 150 AC 000

86

When the rung condition becomes:

True

Accumulated value increments by 1. Bit 14 is set if the AC > 999. Bit 15 is set when AC > PR. Incrementing the accumulated value continues

after the preset value is reached.

Bit 17 is set and stays set until the rung goes false.

False

Accumulated value is retained. Bit 14 - no action is taken. Bit 15 - no action is taken. Bit 17 is reset.

Chapter 8

Timers and Counters

The Up Counter instruction retains its AC value when:

You change the mode to the remote program. The rung condition turns false. A power outage occurs and memory backup is maintained.

Important: Bit 14 of the accumulated value word is set when the accumulated value either overflows or underflows. when a down counter preset is 000, the underflow bit 14 will not be set when the count goes below 0.

Down Counter

Purpose: The Down Counter instruction subtracts one from its accumulated value for each false to true transition of its rung conditions. A count is only added on a false to true transition, so rung conditions must go from true to false and back to true before the next count is registered.

010

When the rung condition becomes:

True

Accumulated value decrements by 1. Bit 14 is set when AC < 000. Bit 15 is reset when AC < PR; counting continues. Bit 16 is set and stays set until the rung goes false.

False

Accumulated value is retained. Bit 14 - no action is taken. Bit 15 - no action is taken. Bit 16 is reset.

Counter Reset

030

CTD

PR 150 AC 000

Purpose: The Counter Reset instruction resets the up counter down counter instructions accumulated value and status bits to 0.

010

030

CTR

PR 150 AC 000

87

Chapter 8

Timers and Counters

When the rung condition becomes:

True

Accumulated value of the specified counter is reset to 000. Status bits (14,15,16,17) are reset.

False

No action is taken.

Keystrokes: You enter an Up Counter, Down Counter or Counter Reset instruction by performing the following steps.

1. Press -(CTU)-, -(CTD)-, or -(CTR)-.

2. Enter <address>. Important: Do not perform steps 3 and 4 for a Counter Reset instruction.

3. Enter <preset value>.

4. Enter <accumulated value>.

Editing in a Completed Rung

You edit an Up Counter, a Down Counter, or a Counter Reset instruction by performing the following steps.

1. Position the cursor over the Up Counter, Down Counter or Counter Reset

you want to change.

2. Press either -(CTU)-, -(CTD)-, -(CTR)-, or any other appropriate

instruction type.

3. Enter <address>.

4. Enter <preset value> if appropriate. Important: Do not perform steps 4 and 5 for a Counter Reset instruction.

5. Enter <accumulated value>.

Chapter Summary

88

We showed you how to use timer and counter instructions to keep track of timed intervals and counted events. The next chapter shows you how to transfer and compare data.

Chapter

Data Manipulation Instructions

Chapter Objectives

Transfer Instructions

In this chapter, you will read about two types of instructions used to transfer and compare data and how to use these instructions to perform operations of data that is stored in the data table. These types of instructions are:

transfer instructions compare instructions

There are two data transfer instructions. They are:

get put

Get

Purpose: A Get instruction accesses all 16 bits of one word location in the data table. It does not determine rung or require logic continuity. A Get also provides a time base for a selectable timed interrupt. In an STI, the Get instruction is the first instruction in the subroutine area. See chapter 15 for more information.

ATTENTION: Use the subroutine area carefully because unintended subroutine execution can cause unexpected machine operation.

Programmed in the condition area of the ladder diagram rung. It can be located at the beginning of a rung or with one or more conditions preceding it. It is always true and intensified.

Get always accesses the word to which it is addressed. It displays a three hexadecimal value of lower 12 bits (bits 0-13) of the specified word.

11111130

238

040

PUT

000

91

Chapter 9

Data Manipulation Instructions

Put

Purpose: A Put instruction receives all 16 bits of data from the immediately preceding Get instruction and stores the data at the specified data table word location. Use with a Get instruction to form a data transfer rung.

Programmed in the output side of the ladder diagram rung. This instruction can have the same address as other instructions in the program. It must be immediately preceded by a Get or a Get-Byte instruction.

11111130

238

040

PUT

000

When rung conditions become:

True

A Get instruction transfers data to the Put instruction. The lower 12 bits are displayed in hexadecimal beneath the Put instruction. Bits 14-17 are transferred but not displayed.

False

Because he Put instruction is retentive, any change in Get instruction data

does not change Put instruction data.

Keystrokes: You enter a Get or Put instruction by performing the following steps.

1. Press -[G]- or -(PUT)-.

2. Enter <address>.

92

Important: Do not perform step 3 for a Put instruction.

3. Enter <data> if appropriate.

Removing

a Get Instruction

You remove a Get instruction by performing the following steps.

1. Position the cursor over the Get instruction you are going to remove.

2. Press [REMOVE] -[G]-.

Removing

a Put Instruction

The only way to remove a Put instruction is to remove the whole rung. See chapter 16.

Chapter 9

Data Manipulation Instructions

Editing

a Get Instruction in a Partially Completed Rung

1. Enter the next instruction.

2. Position the cursor over the Get instruction you want to change.

3. Press -[G]- or any other appropriate instruction type key.

4. Enter <address>.

5. Enter <data> if appropriate.

Editing

a Get or Put Instruction in a Completed Rung

1. Position the cursor over the Get or Put instruction you want to change.

2. Press -[G]-, -(PUT)-, or any other appropriate instruction type key.

3. Enter <address>. Important: Do not perform step 4 for a Put instruction.

4. Enter <data> if appropriate.

Compare Instructions

There are three compare instructions:

equal to less than limit test

Equal To

Purpose: An equal to comparison is made with the Get and Equ instructions. The get value is the changing variable and is compared to the reference value of the Equ instruction for an equal to condition. When the get value equals the equ value, the comparison is true and logic continuity is established. It determines the rung condition. Compares only the lower 12 bits to the immediately preceding get instruction.

12003030

When YYY = 100, GET/EQU comparison is true and 010/02 is energized.

YYY

035

100

Reference Value

If the rung condition becomes:

010

True - If there is equality. False - If there is no equality.

93

Chapter 9

Data Manipulation Instructions

Keystrokes: You enter an Equal To instruction by performing the following steps.

1. Press -[=]-.

2. Enter <address>.

3. Enter <reference value> if appropriate. Removing an Equal To Instruction

You remove an Equal To instruction by performing the following steps.

1. Position the cursor over the Equal To instruction you are going to remove.

2. Press [REMOVE] -[=]-.

Editing

a Completed Rung

You edit an Equal To instruction by performing the following steps.

1. Position the cursor over the Equal To instruction you are going to edit.

2. Press -[=]- or any other appropriate instruction type key.

3. Enter <address>.

4. Enter <reference value> if appropriate.

Less Than

Purpose: The Less Than instruction compares the data in your specified address with the data stored at another address in memory. It determines the rung condition. Compares only the lower 12 bits to the immediately preceding Get instruction.

Programmed after the Get instruction in the condition side of the ladder diagram rung.

12001030

YYY

037

654

010

94

Reference Value

When YYY < 654, GET/LES comparison is true and 010/02 is energized.

The rung condition becomes:

True - If the get value is less than the reference value stored in the

Less Than instruction.

False - If the get value is equal to or greater than the less than value.

Chapter 9

Data Manipulation Instructions

Keystrokes: You enter a Less Than instruction during initial programming by performing the following steps.

1. Press -[<]-.

2. Enter <address>.

3. Enter <reference value>. Removing the Less Than Instruction

You remove a Less Than instruction by performing the following steps.

1. Position the cursor over the Les Than instruction you want to remove.

2. Press [REMOVE] -[<]-. Editing a Completed Rung

You edit a Less Than instruction by performing the following steps

1. Position the cursor over the Less Than instruction you are going to edit.

2. Press -[<]- or any other appropriate data comparison instruction.

3. Enter <address>.

4. Enter (reference value).

Limit Test

Purpose: The limit test checks to see if a byte value is between two reference byte values in the limit test instruction.

Programmed with a Get Byte instruction located in the condition area of the

ladder diagram.

Do not place compare instructions between the Get Byte and

Limit Test instruction.

The Get Byte and Limit Test instructions work only with octal values.

95

Chapter 9

Data Manipulation Instructions

There are two cases for comparison:



YYY

Case 1. Lower Limit



Upper Limit

120060451

YYY

050L200

170

010

If YYY is equal to or greater than 170 and equal to or less than 200, the comparison is true and logic continuity is established. If YYY is less than 170 or greater than 200, the comparison is false and logic continuity is not established.

377

False

200

True

YYY

170

False

000

96

Case 2. Lower Limit  YYY  Upper Limit

120060451

YYY

050L170

200

377

200

170

000

True

YYY

False

YYY

True

010

Chapter 9

Data Manipulation Instructions

If YYY is equal to or less than 200 and equal to or greater than 170, the comparison is false and logic continuity is not established. If YYY

greater than 200 or less than 170, the comparison is true and logic continuity is established.

Keystrokes: You enter a Limit Test instruction by performing the following steps.

1. Press -[L]-.

2. Enter <address>.

3. Enter <upper limit>.

4. Enter <lower limit>. Editing a Completed Rung

You edit the Limit Test comparison by performing the following steps.

Operations Involving Transfer and Comparison Instructions

1. Press -[L]-.

2. Enter <address>.

3. Enter <upper limit>.

4. Enter <lower limit>.

You can perform five operations involving transfer and comparison instructions.

equal to or less than greater than equal to or greater than get byte get byte/put

Equal To or Less Than

Purpose: The equal to/les than comparison is made using the Get, Les, Equ and branching instructions. The get value is the changing value. The Les and Equ instructions are assigned a reference value. When the get value is either less than or equal to the value at Les and Equ instructions, the comparison is true and logic continuity is established.

97

Chapter 9

Data Manipulation Instructions

12004030

When YYY  237, GET/LESEQU comparison is true and 010/03 is energized.

YYY

037

237 037

237

010

Important: Only one Get instruction is required for a parallel comparison. The Les and Equ instructions are programmed in parallel branches.

Keystrokes: You enter an equal to or less than comparison by following the following steps.

1. Press -[G]-.

2. Enter <address>.

3. Enter <reference value>.

4. Press [

]

5. Press -[<]-.

6. Enter <address>.

7. Enter <reference value>.

8. Press [

9. Press -[=]-.

10. Enter the same address as that entered for the Less Than instruction.

11. Enter <reference value>.

12. Press [

]

13. Press -( )-.

14. Enter <address>. Editing the Operation

See the editing for the Get, Les, Equ and Branching instructions.

98

Chapter 9

Data Manipulation Instructions

Greater Than

Purpose: A greater than comparison is also made with the Get/Les pair of instructions. This time the Get instruction BCD value is the reference and the Les instruction BCD value is the changing value. The Les value is compared with to the Get value for a greater than condition. When the Les value is greater than the Get value, the comparison is true and logic continuity is established.

12003030

When YYY > 100, GET/LES comparison is true and 010/02 is energized.

000

010

YYY

Reference Value

Keystrokes: You enter a greater than comparison by performing the following steps.

1. Press -[G]-.

2. Enter <address>.

3. Enter <reference value>.

4. Press -[<]-.

5. Enter <address>.

6. Enter <reference value>. Editing the Operation

See the editing for the Get and Less instructions

010

Equal To or Greater Than

Purpose: This comparison is made using the Get, Les, Equ and branching instructions. The Get value is assigned a reference value. The Les and Equ values are changing and are compared to the Get value. When the Les and Equ values are greater than or equal to the Get value, the comparison is true and logic continuity is established.

12005030

042

440

YYY

042

YYY

Reference Value

When YYY  440, GET/LESEQU comparison is true and 010/04 is energized.

010

99

Chapter 9

Data Manipulation Instructions

Keystrokes: You enter an Equal To or Greater Than comparison by performing the following steps.

1. Press -[G]-.

2. Enter <address>.

3. Enter <reference value>.

4. Press [

5. Press -[=]-.

6. Enter <address>.

7. Enter <reference value>.

8. Press [

9. Press -[<]-.

10. Enter <address>.

11. Enter <reference value>.

12. Press [

13. Press -( )-.

14. Enter <address>. Editing the Operation

See the editing Get, Les, Equ and branching instructions.

910

Get Byte

Purpose: The Get Byte instruction accesses 1 byte (instead of word) from one address in the data table.

The Get Byte instruction can be programmed with a limit test instruction

located in the condition area of the ladder diagram rung.

Use with a Put instruction to transfer either the upper or lower byte to the

upper or lower byte of the Put instruction address.

Do not place compare instructions between the Get Byte and

Limit Test instructions.

Chapter 9

Data Manipulation Instructions

Keystrokes: You enter a Get Byte instruction by performing the following steps.

1. Press -[B]-.

2. Enter <address>.

3. Enter <byte designation>. Editing the Operation

You edit the Get Byte comparison by performing the following steps.

1. Position the cursor over -[B]-.

2. Press -[B]-.

3. Enter <address>.

4. Enter <by designation>.

Get Byte/Put

Purpose: The Get Byte instruction can be programmed either at the beginning of the rung or with one or more condition instructions preceding it. Condition instructions, however, should not be programmed after a Get Byte instruction. When one or more condition instructions precede the Get Byte instruction, they determine whether the rung is true or false.

The Get Byte instruction addresses either the upper or lower byte of a data table word. A 1 is entered after the word address for an upper byte; a 0 is entered for the lower byte.

There are two ways to perform a Get Byte/Put instruction.

Case 1. One Get Byte

XXXD 040

YYY

only these three letters are displayed

The Get Byte instruction is programmed in the condition area of the ladder rung. It tells the processor to make a duplicate of all 8 bits in the addressed byte. When the rung containing the Get Byte/Put instructions goes true, the data is transferred to both the upper and lower byte of the word address of the Put instruction.

PUT ZZZ

ZZZZ

911

Chapter 9

Data Manipulation Instructions

Case 2. Two Get Bytes

XXXD 040

XXXD

WWW

YYY

XXX word address

WWW

YYY

octal values  upper or lower byte

01 lower byte

 upper byte

only these three letters are displayed

PUT BCC

BBCCC

Two Get Byte instructions are programmed in the condition area of the ladder rung. It tells the processor to make a duplicate of all 8 bits in each addressed byte. When the rung containing the Get Byte/Put instructions goes true, the data from the first get byte is transferred into the upper byte of the addressed Put instruction. Also, the data from the second get byte is transferred into the lower byte of the addressed Put instruction.

Keystrokes: You enter a Get Byte/Put instruction by performing the following steps.

1. Press -[B]-.

2. Enter <address>.

3. Enter <byte designation>. Important: Repeat steps 1, 2 and 3 when using two Get Byte instructions.

4. Press -(PUT)-.

5. Enter <address>.

912

Chapter 9

Data Manipulation Instructions

Editing the Operation

You edit a Get Byte/Put instruction by performing the following steps.

6. Position the cursor over -[B]-.

7. Press -[B]-.

8. Enter <address>.

9. Enter <byte designation>. Important: Repeat steps 2, 3 and 4 when using two Get Byte instructions.

10. Press -(PUT)-.

11. Enter <address>.

Chapter Summary

We showed you how to transfer and compare data. Also, we showed you how to use these instructions to perform comparison operations. The next chapter shows you how to perform operations involving three digit and expanded math.

913

Math Instructions

Chapter

Chapter Objectives

This chapter describes two different types of math operations:

three digit math expanded math

Table 10.A lists definitions of some mathematical terms.

Table 10.A Common

Arithmetic T

Terms A B C

Operands Operand A Operand B

Addition Augend + Addend Sum

Subtraction Minuend  Subtrahend Difference

Multiplication Multiplicand Multiplier Product

Division Dividend Divisor Quotient

Square Root Root Square Root

erms

ThreeDigit Math

Your processor can perform four operations using three-digit math:

addition subtraction multiplication division

These operations are not signed functions.

101

Chapter 10

Math Instructions

Addition, Subtraction, Multiplication and Division

Addition

Reports the sum of two values from the two Get instructions immediately preceding the addition instruction. Programmed in the output position of the ladder diagram rung. The sum is stored in the add instruction word address.

030

031

320

380

When the sum exceeds 999, the overflow bit (bit 14) in the add instruction word is set. When the processor is operating in the run, program, or remote test mode, the overflow condition appears on the industrial terminal screen as a “1” preceding the sum.

032

700

Important: If an overflow value (four digits) is used for subsequent comparisons or other arithmetic operations, inaccurate results could occur.

030

999

031

999

032

1998

Subtraction

Reports the difference between two get values immediately preceding the subtraction instruction. The second get word value is subtracted from the first get word value. Programmed in the output position of the ladder diagram rung. The difference is stored in the subtract instruction word address.

070

134

071

039

072

095

When the difference is a negative number, the underflow bit (bit 16) in the subtract instruction word is set. When your processor is in the run, program, or remote test mode, the negative sign appears on the industrial terminal screen preceding the difference.

102

070

100

071

134

072

034

Important: Use only positive values. If you use a negative BCD value for subsequent operation, inaccurate results could occur.

Chapter 10

Math Instructions

Multiplication

Reports the product of two values stored in the Get instruction words immediately preceding the multiply instruction. Programmed in the output position of the ladder diagram. The product is stored in two multiplication instruction words. The first word contains the most significant digit and the second word contains the least significant digit. If the product is less than six digits, leading zeros appear in the product.

130

123

131

061

051

007

052

503

Important: Use consecutive word addresses for the two addresses of the multiply instruction.

Division

Reports the quotient of two values stored in the two Get instructions immediately preceding division instruction. Programmed in the output position of the ladder diagram rung. The quotient is stored in two divide instruction words. The first word contains the most significant word and the second word contains the least significant digit.

140

050

141

025

067

066



002

000

Important: Use consecutive word addresses for the two addresses of the divide instruction. Quotient is expressed as a decimal, accurate to 3 decimal places. Any remaining data is rounded. Division by zero (including 0 : 0) gives the result of 999.999. This result differs from the PLC-2/20 and PLC -2/30 controllers where 0.0 = 1.000.

140

000

141

000

067

066



999

Keystrokes: You enter a three-digit math operation by performing the following keystrokes.

1. Start the rung. Press -[G]-.

2. Enter <address>.

3. Enter <data> if appropriate.

4. Press -[G]-.

5. Enter <address>.

103

Chapter 10

Math Instructions

6. Enter <data> if appropriate.

7. Close the rung by pressing the appropriate math instruction key

(Table 10.B).

Table 10.B Three

Digit Math Functions

Expanded Math

Addition (

Subtraction

Multiplication

Division

+ )

(  )

( x )

( ÷ )

8. Enter <address(es)>. Editing a Completed Rung

You edit a three digit math operation to change an address or the instruction type by performing the following steps.

1. See chapter 9 and follow the editing procedure for a Get instruction.

2. Position the cursor over the math function.

3. Press the appropriate instruction type key.

4. Enter <address(es)>.

The processor can perform four math operations involving two operands:

104

Addition A + B = C Subtraction A - B = C MultiplicationA x B = C Division A

÷ B = C

The processor can perform three additional operations that involve only one operand, the equations are:

Square Root

A = C

Conversion (BCD to Binary) E (BCD) = F (Binary)

Conversion (Binary to BCD) F (Binary) = E (BCD)

You solve these equations with expanded math operations using the EAF function of your processor. Figure 10.1 shows operand and result locations in a ladder diagram rung.

Chapter 10

Math Instructions

Figure 10.1 Primary

Ladder Diagram for EAF Addition

050

051

052

053

000

Operand B Operand A

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

01 040 060

Result (Term C)

Data Address

The data address (operand A) is the starting address of four consecutive data table words that contain the:

augend minuend multiplicand dividend root conversion word

The data table can also contain a default value when performing square roots and conversions. The default value directs the processor to get its data from the rung.

The operand has a format like that shown in Figure 10.2. Enter the instructions for operand A from the keyboard of the 1770-T3 industrial terminal or through ladder diagram instructions. Once you select the data address(s), the EAF automatically reserves the next three addresses (four total) for the remaining words.

105

Chapter 10

Math Instructions

Figure 10.2

Address Format

Data

Operand A is stored in the data table like this:

17 16 15 14 10 7 4 3 0

XSXX M L K

XXXX J H G

XXXX F E D

XXXX C B A

Operand A is displayed in the 1770T3 industrial terminal like this:

MLKJHGFEDCBA

Integer High Word

Integer Low Word

Decimal High Word

Decimal Low Word

•

implied and not displayed.

S = Sign Bit X = Additional Storage Bits

Important: Valid data addresses include the I/O image table and the data table (except word 027). Specifically, valid addresses are from 010 to 026, from 030 to 077, and from 110 to the end of the data table. Data addresses and result addresses must not reside in the input image table.

106

The most significant four bits of the integer high word of the data address (Figure 10.2) are reserved for status bits.

bit 17 - not used bit 16 - sign (+/-) bit 15 - not used bit 14 - not used

There is an implied decimal point between the integer low word and the decimal high word. The decimal point is implied but not displayed (Figure 10.2).

Chapter 10

Math Instructions

Conditioning Instructions

The conditioning instructions (operand B) may require up to four data table words (Figure 10.2). We use Get instructions to enter data for operand B that can contain an:

addend subtrahend multiplier divisor root conversion word

Operand B has the format xxx xxx.xxx xxx. Enter it from the keyboard of the 1770-T3 industrial terminal or through ladder diagram instructions. The number you enter has a fixed decimal point. To include the range of numbers between 999 999.999 999 to 000 000.000 000 requires 12 bits from each of the four data words.

To enter the number MLK takes only one get or one data table word.

+\ - MLK

XXX MLK . XXX XXX

To enter the number MLK JHG takes two gets or two data words.

G G

+\ - MLKJHG

MLK JHG . XXX XXX

To enter the number MLK JHG.FED takes three gets or three data table words.

G G G

+\ - MLKJHG FED

MLK JHG . FED XXX

To enter the number MLK JHG.FED CBA takes four gets or data table words.

G G G G

+\ - MLKJHG FED CBA

MLK JHG . FED CBA

Access an expanded math function by pressing [SHIFT][EAF] or [SHIFT][SCT]. The EAF instruction is an output instruction and must be preceded by the gets of operand B. This operand may be preconditioned but nothing can be programmed between the gets and the EAF instruction. Should you program five gets, the last four gets are the only ones to be processed. The four gets need not have consecutive addresses. They can have any address except 000-007 and 100-107 in the processor work area.

107

Chapter 10

Math Instructions

Figure 10.3

Address Format

Result

17 16 15 14 10 7 4 3 0

XSZ

ML K

Result Address

XXXX J H G

XXXX F E D

XXXX C B A

Operand A is displayed i the 1770T3 industrial terminal like this:

MLKJHGFEDCBA

S = Sign Bit Z = Zero Indicator

= Overflow/Underflow

X = Additional Storage Bits

N + 1

N + 2

N + 3

Result Address

The result address (term C) is the starting address of four consecutive data table words that contain the:

108

sum difference product quotient root converted word

The result word has the format shown in Figure 10.3. The format is similar to the data address except that there are three status bits.

Once you select the result address, the EAF instruction automatically reserves the next three addresses for the remaining words of the result (Figure 10.3). Be careful not to select data and result addresses so close together that the addresses of the operands following the data address overlap the result address.

bit 17 - not used bit 16 - sign bit: 0 = positive (+), 1 = negative (-) bit 15 - zero indicator: 0 = non-zero; 1 = zero result

Chapter 10

Math Instructions

bit 14 - overflow/underflow/illegal bit; significance depends on the

arithmetic operation being performed at the time overflow (addition) - set indicates result exceeds displayable result

overflow (subtraction) - set indicates result exceeds displayable result

overflow or underflow (multiplication) - set indicates result exceeds displayable result

illegal (division) - set indicates division by zero or result exceeds result word range

In this section, unused status bits are shown blank for the following reasons:

Whether the content of an unused status bit in an input word is 0 or 1 is

irrelevant as such bits are ignored in EAF instruction execution.

The EAF instruction reset unused status bits in result words. For simplicity

the bits are left blank.

The processor can “chain” the results of the last executed EAF instruction with the current EAF instruction. You can use the last result as either the augend, minuend, multiplicand or dividend. Or, you can also use the last result as either the addend, subtrahend, multiplier or divisor.

Branch Instructions

The least amount of instructions required to make the processor execute an EAF instruction is shown in Figure 10.1. The instructions composing the three terms A, B, and C are probably in different locations of your ladder diagram. Chances are that you would never see them. You can monitor the values in these instructions using the ladder diagram shown in Figure 10.4. The ladder diagram serves two purposes. It contains both the least amount of instructions required to execute an EAF instruction and display branches. Therefore, you have a choice of using either one of two ladder diagrams to execute an EAF instruction. These two ladder diagrams are named:

primary optional

109

Chapter 10

Math Instructions

Result

Operand A

Operand B

Figure 10.4 Optional

Ladder Diagram for EAF Addition

060

061

062

063

000

040

041

042

043

000

050

051

052

053

000

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

01 040 060

In the optional ladder diagram (Figure 10.4), the first branch contains the result (term C). The second branch contains the data address or operand A (term A). The third branch contains operand B (term B).

Function Numbers

To program a specific operation, enter the appropriate function number (Table 10.C). This entry identifies a specific EAF math operation.

Table 10.C

Function Numbers

EAF

Function

Number

01 02 03 04 05 13 14

Mathematical

Operation

Add Subtract Multiply Divide Square Root BCD to Binary Binary to BCD

Error Handling

Two types of run-time errors can occur when you use EAF instructions. They are illegal opcode and illegal address errors. An illegal opcode occurs if you enter a function number other than 1, 2, 3, 4, 5, 13, or 14. An illegal address error occurs if the operand pointed to by the data address or if the result pointed by the result address is located in the processor’s work areas or in the program areas.

1010

Chapter 10

Math Instructions

Expanded Math Operations

Your processor executes the following expanded math operations and maintains the proper sign of the result:

addition subtraction multiplication division BCD to binary conversion Binary to BCD conversion square root (not a signed function)

Addition, Subtraction, Multiplication, and Division

Addition

Reports the sum (result address) of the augend (operand A, the data address) and the addend (operand B, the conditioning gets). The addition function uses up to 12 digits for each operand. When the sum exceeds 999 999.999 999, the overflow bit (bit 14) in the result address word is set.

060

G 000 040

G 000 050

G 000

061

G 000 041

G 000 051

G 000

062

G 000 042

G 000 052

G 000

063

G 000 043

G 000 053

G 000

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

01 040 060

Important: If an overflow value is used for subsequent comparisons or other arithmetic operations, inaccurate results could occur.

Subtraction

Reports the difference (result address) between two operands, a minuend (data address) and subtrahend (conditioning gets). The operands can use up to 12 digits.

060

G 000 040

G 000 050

G 000

061

G 000 041

G 000 051

G 000

062

G 000 042

G 000 052

G 000

063

G 000 043

G 000 053

G 000

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

02 040 060

1011

Chapter 10

Math Instructions

Multiplication

Reports the product (result address) of a multiplicand (data address) and a multiplier (conditioning gets). Operands can only be six digits.

060

G 000 040

G 000 050

G 000

061

G 000 041

G 000 051

G 000

062

G 000 042

G 000 052

G 000

063

G 000 043

G 000 053

G 000

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

03 040 060

Division

Reports the quotient (result address) of a dividend (data address) and a divisor (conditioning instructions).

060

G 000 040

G 000 050

G 000

061

G 000 041

G 000 051

G 000

062

G 000 042

G 000 052

G 000

063

G 000 043

G 000 053

G 000

Start

Function Number: Data Addr: Result Addr:

Executive Aux

Function

04 040 060

Important: The quotient has at least six decimal digits. Any remaining data is rounded. Division of a number by zero (including 0 : 0) gives the result of

999.999 and the illegal bit is set.

1012

Primary Ladder Diagram Keystrokes: You enter the instructions for a primary ladder diagram to execute

an addition, subtraction, multiplication, or division operation by performing the following steps.

1. Open the rung. Press -[G]-.

2. Enter <address>.

3. Enter <data> if appropriate.

4. Press -[G]-.

5. Enter <address>.

6. Enter <data> if appropriate.

7. Press -[G]-.

8. Enter <address>.

Rockwell Automation 1772-LS, 1772-LSP, D17726.8.6 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Summary of Changes

Table of Contents