Allen-Bradley micrologix 1500 Reference Manual

MicroLogix™ 1200 and MicroLogix 1500

Programmable

Controllers

(Bulletins 1762 and 1764)

Instruction Set

Reference Manual

Important User

Information

Because of the variety of uses for the products described in this publication, those responsible for the application and use of this control equipment must satisfy themselves that all necessary steps have been taken to assure that each application and use meets all performance and safety requirements, including any applicable laws, regulations, codes and standards.

The illustrations, charts, sample programs and layout examples shown in this guide are intended solely for purposes of example. Since there are many variables and requirements associated with any particular installation, Rockwell International Corporation does not assume responsibility or liability (to include intellectual property liability) for actual use based upon the examples shown in this publication.

Rockwell Automation publication SGI-1.1, Safety Guidelines for the

Application, Installation and Maintenance of Solid-State Control

(available from your local Rockwell Automation office), describes some important differences between solid-state equipment and electromechanical devices that should be taken into consideration when applying products such as those described in this publication.

Reproduction of the contents of this copyrighted publication, in whole or part, without written permission of Rockwell Automation, is prohibited.

Throughout this manual we use notes to make you aware of safety considerations:

ATTENTION

!

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

Attention statements help you to:

• identify a hazard

• avoid a hazard

• recognize the consequences

IMPORTANT

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

PLC-5 is a registered trademark; and MicroLogix, SLC 500, RSLogix, and RSLinx are trademarks of Rockwell Automation.

Modbus is a trademark of Schneider Electric Incorporated.

DeviceNet is a trademark of Open DeviceNet Vendor Association (ODVA).

3

Summary of Changes

The information below summarizes the changes to this manual since the last printing as publication 1762-RM001B-US-P, April 2000.

To help you locate new and updated information in this release of the manual, we have included change bars as shown to the right of this paragraph.

Firmware Revision History

Features are added to the controllers through firmware upgrades. Use the listing below to be sure that your controller’s firmware is at the level you need. Firmware upgrades are not required, except to allow you access to the new features.

MicroLogix 1200

Catalog

Number

1762-L24AWA

1762-L24BWA

1762-L40AWA

1762-L40BWA

1762-L24AWA

1762-L24BWA

1762-L40AWA

1762-L40BWA

1762-L24AWA

1762-L24BWA

1762-L40AWA

1762-L40BWA

Series

Letter

A

Revision

Letter

A

Firmware

Release No.

FRN1

A

B

B

A

FRN2

FRN3

1762-L24BXB

1762-L40BXB

B A FRN3

Release Date Enhancement

March 2000

May 2000

Initial product release.

The trim pots (trimming potentiometers) on the controller operated in reverse of the ladder logic. Corrected.

November 2000 MicroLogix 1200 controllers now offer:

•

•

•

•

•

•

Full ASCII (read/write)

PTO Controlled Stop

PWM Ramping

RTC and String Messaging

Static Data File Protection

Comms Reset Pushbutton Bit

November 2000 Initial product release. Supports all the features listed above for the 1762-L24xWA and 1762-L40xWA controllers.

Publication 1762-RM001C-EN-P - November 2000

Summary of Changes 4

MicroLogix 1500

Catalog

Number

1764-LSP A

Series

Letter

1764-LSP A

1764-LSP

1764-LRP

1764-LSP

1764-LRP

B

B

B

B

A

A

B

B

Revision

Letter

B

C

Firmware

Release No.

FRN2

FRN3

FRN4

FRN4

FRN5

FRN5

Release Date Enhancement

February 1999 Initial product release.

October 1999 MicroLogix 1500 Controllers with 1764-LSP Processor can now be used with Compact I/O (Bulletin 1769) Expansion Cables and

Power Supplies.

April 2000

April 2000

MicroLogix 1500 Controllers with 1764-LSP Processor can now use:

•

•

•

•

•

•

String Data File Type

ASCII Instruction Set Support

Modbus RTU Slave protocol

Ramping, when using PWM outputs

Static Data File Protection

RTC Messaging

Initial product release. MicroLogix 1500 Controllers with

1764-LRP Processor has all the features of the 1764-LSP, plus:

•

•

Second communications port (isolated RS-232)

Data Logging capability

October 2000 For both the 1764-LSP and LRP processors:

October 2000

•

When using the PTO feature, the controller can now perform a controlled stop when using PTO outputs. The deceleration phase of the PTO can be initiated early via

• ladder logic.

Enhanced program compare bit functionality in the Memory

Module.


New Information


The table below lists sections that document new features and additional information about existing features.

For This New Information

Added MicroLogix 1200 1762-L24BXB and 1762-L40BXB Controllers

Added configuration information for several new I/O modules:

•

•

1762-IQ16, -OA8, -OB8, -OB16, -OW16, -IF4

1769-OB16P and -IT6

Added section on Configuring Expansion I/O Using RSLogix 500

Made minor changes to clarify data file numbering.

See

Chapter 1, 5, 6

Chapter 1

Modified section on Writing Data to the Real-Time Clock

In the Communications Status File, General Channel Status Block, Bit 15, the Comms Toggle Push Button Bit, is now valid for MicroLogix 1200 and

MicroLogix 1500 (previously was only the MicroLogix 1500).

Added IMPORTANT notes about using the High-Speed Counter (HSC).

Added IMPORTANT notes about using the High-Speed Outputs (PTO and

PWM).

Modified text that describes the PWM Accel/Decel Delay (ADD) parameter.

Added PTO Controlled Stop (CS) parameter (MicroLogix 1500 only).

Chapter 1

Chapter 2

Chapter 3

Chapter 3

Chapter 5

Chapter 6

Chapter 6

Modified text that describes the Scale (SCL) instruction.

Corrected text for the PID Reset Term (Ti). The last sentence now reads:

“A value of 1 adds the maximum integral term into the PID equation.”

(previously said that “a value of 1 adds the minimum integral term...”)

MicroLogix 1200 Series B Controllers can use the entire set of ASCII instructions

Added section on Programming ASCII Instructions with information on how to prevent communications shut-down when using ASCII instructions.

Chapter 6

Chapter 10

Chapter 19

Chapter 20

Chapter 20

Added Ctrl-characters to the ASCII Character Set chart.

Added MSG File Element description.

Chapter 20

Chapter 21

The ASCII String Manipulation Error bit (S:5/15) now applies to

MicroLogix 1200 Series B Controllers as well as the MicroLogix 1500.

Appendix C

Added Fault Classification (non-user, recoverable, non-recoverable) to the

Fault Messages troubleshooting table.

Appendix D

Added new Error Code:

001A - User Program Incompatible with OS at Power-Up

Added alphabetical list of instructions for easy reference.

Appendix D

Inside Back

Cover

Appendix E ASCII Protocol can be used by MicroLogix 1200 Series B Controllers as well as the MicroLogix 1500.

Updated Instruction Execution Times Appendix A and B, and throughout manual




i

Table of Contents

Preface

I/O Configuration

Who Should Use this Manual . . . . . . . . . . . . . . . . . . . . . . . . P-1

Purpose of this Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

Common Techniques Used in this Manual. . . . . . . . . . . . . . . P-2

Rockwell Automation Support . . . . . . . . . . . . . . . . . . . . . . . P-3

Chapter 1

Embedded I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

MicroLogix 1200 Expansion I/O . . . . . . . . . . . . . . . . . . . . . . 1-3

MicroLogix 1200 Expansion I/O Memory Mapping. . . . . . . . . 1-4

MicroLogix 1500 Compact™ Expansion I/O. . . . . . . . . . . . . . 1-7

MicroLogix 1500 Compact™ Expansion I/O Memory Mapping 1-9

I/O Addressing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

I/O Forcing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Input Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Latching Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Configuring Expansion I/O Using RSLogix 500 . . . . . . . . . . 1-18

Controller Memory and File

Types

Function Files

Programming Instructions

Overview

Chapter 2

Controller Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Data Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Protecting Data Files During Download. . . . . . . . . . . . . . . . . 2-6

Static File Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Password Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Clearing the Controller Memory . . . . . . . . . . . . . . . . . . . . . 2-10

Allow Future Access Setting (OEM Lock). . . . . . . . . . . . . . . 2-10

Chapter 3

Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Real-Time Clock Function File . . . . . . . . . . . . . . . . . . . . . . . 3-3

Trim Pot Information Function File . . . . . . . . . . . . . . . . . . . . 3-5

Memory Module Information Function File . . . . . . . . . . . . . . 3-6

DAT Function File (MicroLogix 1500 only) . . . . . . . . . . . . . . 3-9

Base Hardware Information Function File . . . . . . . . . . . . . . 3-12

Communications Status File . . . . . . . . . . . . . . . . . . . . . . . . 3-13

Input/Output Status File . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18

Chapter 4

Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Using the Instruction Descriptions. . . . . . . . . . . . . . . . . . . . . 4-2

Publication 1762-RM001C-EN-P

Table of Contents ii

Using the High-Speed

Counter

Using High-Speed Outputs

Chapter 5

High-Speed Counter (HSC) Function File . . . . . . . . . . . . . . . 5-2

High-Speed Counter Function File Sub-Elements Summary . . 5-4

HSC Function File Sub-Elements . . . . . . . . . . . . . . . . . . . . . . 5-5

HSL - High-Speed Counter Load . . . . . . . . . . . . . . . . . . . . . 5-26

RAC - Reset Accumulated Value . . . . . . . . . . . . . . . . . . . . . 5-27

Chapter 6

PTO - Pulse Train Output. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Pulse Train Output Function. . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Pulse Train Outputs (PTO) Function File. . . . . . . . . . . . . . . . 6-6

Pulse Train Output Function File Sub-Elements Summary . . . 6-7

PWM - Pulse Width Modulation . . . . . . . . . . . . . . . . . . . . . 6-18

PWM Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18

Pulse Width Modulation (PWM) Function File . . . . . . . . . . . 6-19

Pulse Width Modulated Function File Elements Summary . . 6-20

Chapter 7

Relay-Type (Bit) Instructions

XIC - Examine if Closed

XIO - Examine if Open . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

OTE - Output Energize. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

OTL - Output Latch, OTU - Output Unlatch . . . . . . . . . . . . . 7-4

ONS - One Shot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5

OSR - One Shot Rising, OSF - One Shot Falling . . . . . . . . . . . 7-6

Timer and Counter

Instructions

Compare Instructions

Chapter 8

Timer Instructions Overview . . . . . . . . . . . . . . . . . . . . . . . . 8-1

TON - Timer, On-Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4

TOF - Timer, Off-Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

RTO - Retentive Timer, On-Delay . . . . . . . . . . . . . . . . . . . . . 8-6

How Counters Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7

CTU - Count Up, CTD - Count Down . . . . . . . . . . . . . . . . . . 8-9

RES - Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10

Chapter 9

Using the Compare Instructions . . . . . . . . . . . . . . . . . . . . . . 9-2

EQU - Equal, NEQ - Not Equal . . . . . . . . . . . . . . . . . . . . . . . 9-3

GRT - Greater Than, LES - Less Than . . . . . . . . . . . . . . . . . . 9-4

GEQ - Greater Than or Equal To, LEQ - Less Than or Equal To 9-5

MEQ - Mask Compare for Equal . . . . . . . . . . . . . . . . . . . . . . 9-6

LIM - Limit Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7


Math Instructions

Conversion Instructions

Logical Instructions

Move Instructions

File Instructions

Table of Contents iii

Chapter 10

Using the Math Instructions . . . . . . . . . . . . . . . . . . . . . . . . 10-2

Updates to Math Status Bits . . . . . . . . . . . . . . . . . . . . . . . . 10-3

ADD - Add, SUB - Subtract . . . . . . . . . . . . . . . . . . . . . . . . . 10-4

MUL - Multiply, DIV - Divide . . . . . . . . . . . . . . . . . . . . . . . 10-5

NEG - Negate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

CLR - Clear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

SCL - Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

SCP - Scale with Parameters . . . . . . . . . . . . . . . . . . . . . . . . 10-8

SQR - Square Root . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-9

SWP - Swap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-10

Chapter 11

Using Decode and Encode Instructions . . . . . . . . . . . . . . . . 11-1

DCD - Decode 4 to 1-of-16 . . . . . . . . . . . . . . . . . . . . . . . . . 11-2

ENC - Encode 1-of-16 to 4 . . . . . . . . . . . . . . . . . . . . . . . . . 11-3

FRD - Convert from Binary Coded Decimal (BCD). . . . . . . . 11-4

TOD - Convert to Binary Coded Decimal (BCD) . . . . . . . . . 11-8

Chapter 12

Using Logical Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . 12-1

Updates to Math Status Bits . . . . . . . . . . . . . . . . . . . . . . . . 12-2

AND - Bit-Wise AND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-3

OR - Logical OR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-4

XOR - Exclusive OR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-5

NOT - Logical NOT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-6

Chapter 13

MOV - Move . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-1

MVM - Masked Move . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3

Chapter 14

COP - Copy File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-2

FLL - Fill File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-3

BSL - Bit Shift Left . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-4

BSR - Bit Shift Right . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-6

FFL - First In, First Out (FIFO) Load . . . . . . . . . . . . . . . . . . 14-8

FFU - First In, First Out (FIFO) Unload . . . . . . . . . . . . . . . 14-11

LFL - Last In, First Out (LIFO) Load . . . . . . . . . . . . . . . . . . 14-14

LFU - Last In, First Out (LIFO) Unload. . . . . . . . . . . . . . . . 14-17


Table of Contents iv

Sequencer Instructions

Chapter 15

SQC- Sequencer Compare . . . . . . . . . . . . . . . . . . . . . . . . . 15-2

SQO- Sequencer Output. . . . . . . . . . . . . . . . . . . . . . . . . . . 15-5

SQL - Sequencer Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-8

Chapter 16

Program Control Instructions

JMP - Jump to Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-1

LBL - Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-2

JSR - Jump to Subroutine . . . . . . . . . . . . . . . . . . . . . . . . . . 16-2

SBR - Subroutine Label. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-3

RET - Return from Subroutine. . . . . . . . . . . . . . . . . . . . . . . 16-3

SUS - Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-4

TND - Temporary End . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-4

END - Program End . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-5

MCR - Master Control Reset . . . . . . . . . . . . . . . . . . . . . . . . 16-5

Chapter 17

Input and Output Instructions

IIM - Immediate Input with Mask . . . . . . . . . . . . . . . . . . . . 17-1

IOM - Immediate Output with Mask . . . . . . . . . . . . . . . . . . 17-3

REF- I/O Refresh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17-4

Using Interrupts

Chapter 18

Information About Using Interrupts . . . . . . . . . . . . . . . . . . 18-2

User Interrupt Instructions . . . . . . . . . . . . . . . . . . . . . . . . . 18-7

INT - Interrupt Subroutine . . . . . . . . . . . . . . . . . . . . . . . . . 18-7

STS - Selectable Timed Start . . . . . . . . . . . . . . . . . . . . . . . . 18-8

UID - User Interrupt Disable. . . . . . . . . . . . . . . . . . . . . . . . 18-9

UIE - User Interrupt Enable . . . . . . . . . . . . . . . . . . . . . . . 18-10

UIF - User Interrupt Flush . . . . . . . . . . . . . . . . . . . . . . . . 18-11

Using the Selectable Timed Interrupt (STI) Function File . . 18-12

Using the Event Input Interrupt (EII) Function File . . . . . . 18-17

Chapter 19

Process Control Instruction

The PID Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-1

The PID Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-2

PD Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-2

PID - Proportional Integral Derivative . . . . . . . . . . . . . . . . . 19-3

Input Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-4

Output Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-7

Tuning Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-8

Runtime Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-16

Analog I/O Scaling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-17

Application Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-18

Application Examples. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-22


Table of Contents v

ASCII Instructions

Chapter 20

General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-1

ASCII Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-1

Instruction Types and Operation. . . . . . . . . . . . . . . . . . . . . 20-2

Protocol Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-4

String (ST) Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-5

Control Data File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-6

ACL - ASCII Clear Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . 20-7

AIC - ASCII Integer to String . . . . . . . . . . . . . . . . . . . . . . . . 20-8

AWA - ASCII Write with Append. . . . . . . . . . . . . . . . . . . . . 20-9

AWT - ASCII Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-11

ABL - Test Buffer for Line . . . . . . . . . . . . . . . . . . . . . . . . . 20-14

ACB - Number of Characters in Buffer. . . . . . . . . . . . . . . . 20-15

ACI - String to Integer . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-16

ACN - String Concatenate . . . . . . . . . . . . . . . . . . . . . . . . . 20-18

AEX - String Extract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-19

AHL - ASCII Handshake Lines. . . . . . . . . . . . . . . . . . . . . . 20-20

ARD - ASCII Read Characters . . . . . . . . . . . . . . . . . . . . . . 20-22

ARL - ASCII Read Line . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-23

ASC - String Search. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-25

ASR - ASCII String Compare . . . . . . . . . . . . . . . . . . . . . . . 20-26

Timing Diagram for ARD, ARL, AWA, and AWT Instructions 20-28

Using In-line Indirection . . . . . . . . . . . . . . . . . . . . . . . . . . 20-29

ASCII Instruction Error Codes . . . . . . . . . . . . . . . . . . . . . . 20-30

ASCII Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-31

Chapter 21

Communications Instructions Messaging Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-1

MSG - Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-3

The Message File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-4

Local Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-7

Configuring a Local Message. . . . . . . . . . . . . . . . . . . . . . . . 21-9

Remote Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-16

Configuring a Remote Message . . . . . . . . . . . . . . . . . . . . . 21-18

MSG Instruction Error Codes. . . . . . . . . . . . . . . . . . . . . . . 21-21

Timing Diagram for the MSG Instruction . . . . . . . . . . . . . . 21-23

SVC - Service Communications . . . . . . . . . . . . . . . . . . . . . 21-26

MSG Instruction Ladder Logic . . . . . . . . . . . . . . . . . . . . . . 21-28

Local Messaging Examples . . . . . . . . . . . . . . . . . . . . . . . . 21-29


Table of Contents vi

Data Logging

(MicroLogix 1500 1764-LRP

Processor only)

MicroLogix 1200 Memory

Usage and Instruction

Execution Time

MicroLogix 1500 Memory

Usage and Instruction

Execution Time

System Status File

Fault Messages and Error

Codes

Protocol Configuration

Chapter 22

Queues and Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-2

Configuring Data Log Queues . . . . . . . . . . . . . . . . . . . . . . 22-6

DLG - Data Log Instruction. . . . . . . . . . . . . . . . . . . . . . . . . 22-8

Data Log Status File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-9

Retrieving (Reading) Records . . . . . . . . . . . . . . . . . . . . . . 22-11

Accessing the Retrieval File . . . . . . . . . . . . . . . . . . . . . . . 22-11

Conditions that Will Erase the Data Retrieval File . . . . . . . 22-13

Appendix A

Programming Instructions Memory Usage and Execution Time A-1

MicroLogix 1200 Scan Time Worksheet . . . . . . . . . . . . . . . . . A-7

Appendix B

Programming Instructions Memory usage and Execution Time B-1

MicroLogix 1500 Scan Time Worksheet . . . . . . . . . . . . . . . . . B-6

Appendix C

Status File Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2

Status File Details. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3

Appendix D

Identifying Controller Faults . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Contacting Rockwell Automation for Assistance. . . . . . . . . . . D-9

Appendix E

DH-485 Communication Protocol . . . . . . . . . . . . . . . . . . . . . E-2

DF1 Full-Duplex Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . E-5

DF1 Half-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . E-6

Modbus™ RTU Slave Protocol . . . . . . . . . . . . . . . . . . . . . . . E-9

ASCII Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-13

Glossary

Index

MicroLogix 1200 and 1500 Alphabetical List of Instructions


1

Preface

Read this preface to familiarize yourself with the rest of the manual. It provides information concerning:

• who should use this manual

• the purpose of this manual

• related documentation

• conventions used in this manual

•

Rockwell Automation support

Who Should Use this

Manual

Use this manual if you are responsible for designing, installing, programming, or troubleshooting control systems that use MicroLogix

1200 or MicroLogix 1500 controllers.

You should have a basic understanding of electrical circuitry and familiarity with relay logic. If you do not, obtain the proper training before using this product.

Purpose of this Manual

This manual is a reference guide for MicroLogix 1200 and MicroLogix

1500 controllers. It describes the procedures you use to program and troubleshoot your controller. This manual:

• gives you an overview of the file types used by the controllers

• provides the instruction set for the controllers

• contains application examples to show the instruction set in use


Preface 2

Related Documentation

The following documents contain additional information concerning

Rockwell Automation products. To obtain a copy, contact your local

Rockwell Automation office or distributor.

For

Information on understanding and applying micro controllers.

Information on mounting and wiring the MicroLogix 1200 Programmable

Controller, including a mounting template and door labels.

Detailed information on planning, mounting, wiring, and troubleshooting your MicroLogix 1200 system.

Read this Document

MicroMentor

MicroLogix 1200 Programmable

Controllers Installation Instructions


Controllers User Manual

Document Number

1761-MMB

1762-IN006C-MU-P

1762-UM001B-EN-P

Information on mounting and wiring the MicroLogix 1500 Base Units, including a mounting template for easy installation

Detailed information on planning, mounting, wiring, and troubleshooting your MicroLogix 1500 system.

A description on how to install and connect an AIC+. This manual also contains information on network wiring.

Information on how to install, configure, and commission a DNI

Information on DF1 open protocol.


Controllers Base Unit Installation

Instructions


Controllers User Manual

1764-UM001A-US-P

Advanced Interface Converter (AIC+) User

Manual

1761-6.4

DeviceNet™ Interface User Manual

DF1 Protocol and Command Set

Reference Manual

Allen-Bradley Programmable Controller

Grounding and Wiring Guidelines

1764-IN001A-ML-P

1761-6.5

1770-6.5.16

1770-4.1

In-depth information on grounding and wiring Allen-Bradley programmable controllers

A description of important differences between solid-state programmable controller products and hard-wired electromechanical devices

Application Considerations for

Solid-State Controls

An article on wire sizes and types for grounding electrical equipment

SGI-1.1

National Electrical Code - Published by the National Fire

Protection Association of Boston, MA.

Allen-Bradley Publication Index SD499 A complete listing of current documentation, including ordering instructions. Also indicates whether the documents are available on

CD-ROM or in multi-languages.

A glossary of industrial automation terms and abbreviations Allen-Bradley Industrial Automation

Glossary

AG-7.1

Common Techniques

Used in this Manual

The following conventions are used throughout this manual:

•

Bulleted lists such as this one provide information, not procedural steps.

•

Numbered lists provide sequential steps or hierarchical information.

•

Italic type is used for emphasis.

•

Change bars appear beside information that has been changed or added since the last revision of this manual. Change bars appear in the margin as shown to the right of this paragraph.


Preface 3

Rockwell Automation

Support

Rockwell Automation offers support services worldwide, with over 75

Sales/Support Offices, 512 authorized Distributors and 260 authorized

Systems Integrators located throughout the United States alone, plus

Rockwell Automation representatives in every major country in the world.

Local Product Support

Contact your local Rockwell Automation representative for:

• sales and order support

• product technical training

• warranty support

• support service agreements

Technical Product Assistance

If you need to contact Rockwell Automation for technical assistance,

please review the Fault Messages and Error Codes on page D-1 and the

Troubleshooting appendix in your controller’s User Manual first. Then call your local Rockwell Automation representative. Rockwell Automation phone numbers appear on the back of this manual.

Your Questions or Comments on this Manual

If you find a problem with this manual, or you have any suggestions for how this manual could be made more useful to you, please contact us at the address below:

Rockwell Automation

Control and Information Group

Technical Communication, Dept. A602V

P.O. Box 2086

Milwaukee, WI 53201-2086 or visit our internet page at: http://www.ab.com/micrologix or http://www.rockwellautomation.com


Preface 4


1

Embedded I/O

Chapter

1

I/O Configuration

This section discusses the various aspects of Input and Output features of the MicroLogix 1200 and MicroLogix 1500 controllers. Each controller comes with a certain amount of embedded I/O, which is physically located on the controller. The controller also allows for adding expansion I/O.

This section discusses the following I/O functions:

•

Embedded I/O on page 1-1

•

MicroLogix 1200 Expansion I/O on page 1-3

•

MicroLogix 1200 Expansion I/O Memory Mapping on page 1-4

•

MicroLogix 1500 Compact™ Expansion I/O on page 1-7

•

MicroLogix 1500 Compact™ Expansion I/O Memory Mapping on page 1-9

•

I/O Addressing on page 1-13

•

I/O Forcing on page 1-14

•

Input Filtering on page 1-14

•

Latching Inputs on page 1-15

The MicroLogix 1200 and 1500 provide discrete I/O that is built into the controller as listed in the following table. These I/O points are referred to as

Embedded I/O.

Controller Family

MicroLogix 1200

Controllers

Quantity

1762-L24BWA 14

1762-L24AWA 14

1762-L24BXB 14

Inputs

Type

24V dc

120V ac

24V dc

1762-L40BWA 24

1762-L40AWA 24

1762-L40BXB 24

MicroLogix 1500

Base Units

1764-24BWA 12

1764-24AWA 12

1764-28BXB 16

24V dc

120V ac

24V dc

24V dc

120V ac

24V dc

12

12

12

Quantity

Outputs

Type

10

10

10 relay relay

16

5 relay

5 FET relay

16

16 relay

8 relay

8 FET relay relay

6 relay

6 FET


1-2 I/O Configuration

AC embedded inputs have fixed input filters. DC embedded inputs have configurable input filters for a number of special functions that can be used in your application. These are: high-speed counting, event interrupts, and latching inputs. The 1764-28BXB has two high-speed outputs for use as pulse train output (PTO) and/or pulse width modulation (PWM) outputs. The 1762-L24BXB and -L40BXB each have one high-speed output.


MicroLogix 1200

Expansion I/O

I/O Configuration 1-3

If the application requires more I/O than the controller provides, you can attach I/O modules. These additional modules are called expansion I/O.

Expansion I/O Modules

MicroLogix 1200 expansion I/O (Bulletin 1762) is used to provide discrete and analog inputs and outputs and, in the future, specialty modules. For the MicroLogix 1200, you can attach up to six additional I/O modules.

The number of 1762 I/O modules that can be attached to the MicroLogix

1200 is dependent on the amount of power required by the I/O modules.

See your MicroLogix 1200 User Manual, publication 1762-UM001A-US-P for more information on valid configurations.

NOTE

Visit the MicroLogix web site (http://www.ab.com/ micrologix.) for the MicroLogix 1200 Expansion I/O

System Qualifier.

Addressing Expansion I/O Slots

The figure below shows the addressing for the MicroLogix 1200 and its

I/O.

The expansion I/O is addressed as slots 1 through 6 (the controller’s embedded I/O is addressed as slot 0). Modules are counted from left to right as shown below.

Embedded I/O = Slot 0

NOTE

Expansion I/O

In most cases, you can use the following address format:

X:s/b (X = file type letter, s = slot number, b = bit number)

See I/O Addressing on page 1-13 for complete

information on address formats.



MicroLogix 1200

Expansion I/O Memory

Mapping

Discrete I/O Configuration

1762-IA8 and 1762-IQ8 Input Image

For each input module, the input data file contains the current state of the field input points. Bit positions 0 through 7 correspond to input terminals

0 through 7.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x x x x x r r r r r r r r r = read only, x = not used, always at a 0 or OFF state

1762-IQ16 Input Image

For each input module, the input data file contains the current state of the field input points. Bit positions 0 through 15 correspond to input terminals 0 through 15.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 r r r r r r r r r r r r r r r r r = read only

1762-OA8, 1762-OB8, and 1762-OW8 Output Image

For each output module, the output data file contains the controller-directed state of the discrete output points. Bit positions 0 through 7 correspond to output terminals 0 through 7.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 0 0 0 0 0 0 0 0 r/w r/w r/w r/w r/w r/w r/w r/w r/w = read and write, 0 = always at a 0 or OFF state

1762-OB16 and 1762-OW16 Output Image

For each output module, the output data file contains the controller-directed state of the discrete output points. Bit positions 0 through 15 correspond to output terminals 0 through 15.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w = read and write



Analog I/O Configuration

1762-IF2OF2 Input Data File

For each input module, slot x, words 0 and 1 contain the analog values of the inputs. The module can be configured to use either raw/proportional data or scaled-for-PID data. The input data file for each configuration is shown below.

Table 1.1 Raw/Proportional Format

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 0 Channel 0 Data 0 to 32768

1 0 Channel 1 Data 0 to 32768

0

0

0

0

0

0

2 reserved

3 reserved

4 reserved

5 U0 O0 U1 O1 reserved

S1 S0

Table 1.2 Scaled-for-PID Format

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 0 0 Channel 0 Data 0 to 16,383


0

0

0

0

2 reserved

3 reserved

4 reserved

5 U0 O0 U1 O1 reserved

S1 S0

The bits are defined as follows:

•

Sx = General status bits for channels 0 and 1. This bit is set when an error (over- or under-range) exists for that channel, or there is a general module hardware error.

•

Ox = Over-range flag bits for channels 0 and 1. These bits can be used in the control program for error detection.

•

Ux = Under-range flag bits for channels 0 and 1. These bits can be used in the control program for error detection.




1762-IF2OF2 Output Data File

For each module, slot x, words 0 and 1 contain the channel output data.

Table 1.3 Raw/Proportional Format

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 0 Channel 0 Data 0 to 32,768

1 0 Channel 1 Data 0 to 32,768

0

0

0

0

0

0

Table 1.4 Scaled-for-PID Format

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0



0

0

0

0

1762-IF4 Input Data File

For each module, slot x, words 0 and 1 contain the analog values of the inputs. The module can be configured to use either raw/proportional data or scaled-for-PID data. The input data file for either configuration is shown below.

rd Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 SGN0 Channel 0 Data




4 reserved

5 U0 O0 U1 O1 U2 O2 U3 O3 reserved

6 reserved

S3 S2 S1 S0


• Sx = General status bits for channels 0 through 3. This bit is set when an error

(over- or under-range) exists for that channel, or there is a general module hardware error.

• Ox = Over-range flag bits for channels 0 through 3. These bits are set when the input signal is above the user-specified range. The module continues to convert data to the maximum full range value during an over-range condition.

The bits reset when the over-range condition clears.

• UIx = Under-range flag bits for input channels 0 through 3. These bits are set when the input signal is below the user-specified range. The module continues to convert data to the maximum full range value during an under-range condition. The bits reset when the under-range condition clears.

• SGNx = The sign bit for channels 0 through 3.

MicroLogix 1500

Compact™

Expansion I/O


If the application requires more I/O than the controller provides, you can attach I/O modules. These additional modules are called expansion I/O.

Expansion I/O Modules

Compact I/O (Bulletin 1769) is used to provide discrete and analog inputs and outputs and, in the future, specialty modules. For the MicroLogix

1500, you can attach up to eight additional I/O modules. The number of modules that can be attached is dependent on the amount of power required by the I/O modules.

See your MicroLogix 1500 User Manual, publication 1764-UM001A-US-P, for more information on valid configurations.

NOTE

Visit the MicroLogix web site (http://www.ab.com/ micrologix.) for the MicroLogix 1500 Expansion I/O

System Qualifier.

Addressing Expansion I/O

The figure below shows the addressing for the MicroLogix 1500 and its

I/O.

The expansion I/O is addressed as slots 1 through 8 (the controller’s embedded I/O is addressed as slot 0). Power supplies and cables are not counted as slots, but must be added to the RSLogix 500 project in the I/O configuration. Modules are counted from left to right on each bank as shown in the illustrations below.

Figure 1.1 Vertical Orientation


Expansion

I/O Bank 0

Expansion

I/O Bank 1



Figure 1.2 Horizontal Orientation


NOTE

Expansion

I/O Bank 0

Expansion

I/O Bank 1

In most cases, you can use the following address format:

X:s/b (X = file type letter, s = slot number, b = bit number)

See I/O Addressing on page 1-13 for complete

information on address formats.

Expansion Power Supplies and Cables

To use a MicroLogix 1500 controller with a 1769 Expansion I/O Power

Supply, verify that you have the following:

•

MicroLogix 1500 Processor:

Catalog Number 1764-LSP, FRN 3 and higher

Catalog Number 1764-LRP, FRN 4 and higher

•

Operating System Version: You can check the FRN by looking at word

S:59 (Operating System FRN) in the Status File.

IMPORTANT

If your processor is at an older revision, you must upgrade the operating system to FRN 3 or higher to use an expansion cable and power supply. On the Internet, go to http://www.ab.com/micrologix to download the operating system upgrade. Enter MicroLogix 1500; go to

Tools and Tips.

ATTENTION

LIMIT OF ONE EXPANSION POWER SUPPLY AND CABLE

!

The expansion power supply cannot be connected directly to the controller. It must be connected using one of the expansion cables. Only one expansion power supply may be used in a MicroLogix 1500 system.

Exceeding these limitations may damage the power supply and result in unexpected operation.



MicroLogix 1500

Compact™ Expansion

I/O Memory Mapping

Discrete I/O Configuration

1769-IA8I Input Image

For each input module, the input data file contains the current state of the field input points. Bit positions 0 through 7 correspond to input terminals

0 through 7, bits 8 through 15 are not used.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x x x x x r r r r r r r r r = read, x = not used, always at a 0 or OFF state

1769-IM12 Input Image

For each input module, the input data file contains the current state of the field input points. Bit positions 0 through 11 correspond to input terminals 0 through 11, bits 12 through 15 are not used.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x r r r r r r r r r r r r r = read, x = not used, always at a 0 or OFF state

1769-IA16 and 1769-IQ16 Input Image

For each input module, the input data file contains the current state of the field input points. Bit positions 0 through 15 correspond to input terminals 0 through 15.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 r r r r r r r r r r r r r r r r r = read




1769-IQ6XOW4 Input Image

For each module, the input data file contains the current state of the field input points. Bit positions 0 through 5 correspond to input terminals 0 through 5, bits 6 through 15 are not used.

Input Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x x x x x x x r r r r r r r = read, x = not used, always at a 0 or OFF state

1769-IQ6XOW4 Output Image

For each module, the output data file contains the current state of the control program’s directed state of the discrete output points. Bit positions

0 through 3 correspond to output terminals 0 through 3, bits 4 through 15 are not used.

Output Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x x x x x x x x x r/w r/w r/w r/w r/w = read and write, x = not used, always at a 0 or OFF state

1769-OA8, 1769-OW8, and 1769-OW8I Output Image


0 through 7 correspond to output terminals 0 through 7, bits 8 through 15 are not used.


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 x x x x x x x x r/w r/w r/w r/w r/w r/w r/w r/w r/w = read and write, x = not used, always at a 0 or OFF state

1769-OB16, 1769-OB16P and 1769-OV16 Output Image


0 through 15 correspond to output terminals 0 through 15.


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w = read and write


Analog I/O Configuration

1769-IF4 Input Data File

For each input module, words 0 through 3 contain the analog values of the inputs.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 SGN Analog Input Data Channel 0




4 not used

5 U0 O0 U1 O1 U2 O2 U3 O3 Set to 0

S3 S2 S1 S0


•

SGN = Sign bit in two’s complement format.

•

Sx = General status bits for channels 0 through 3. This bit is set (1) when an error (over- or under-range) exists for that channel.

•

Ux = Under-range flag bits for channels 0 through 3. These bits can be used in the control program for error detection.

•

Ox = Over-range flag bits for channels 0 through 3. These bits can be used in the control program for error detection.

1769-OF2 Output Data File

For each module, words 0 and 1 in the output data file contain the channel 0 and channel 1 output data.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 SGN Channel 0 Data 0 to 32,768

1 SGN Channel 1 Data 0 to 32,768

SGN = Sign bit in two’s complement format.



Specialty I/O Configuration

1769-IT6 Thermocouple Module Input Data File

The input data file contains the analog values of the inputs.

Bit Position

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 Analog Input Data Channel 0






6 OC7 OC6 OC5 OC4 OC3 OC2 OC1 OC0 S7 S6 S5 S4 S3 S2 S1 S0

7 U0 O0 U1 U0 U2 O2 U3 O3 U4 O4 U5 O5 U6 O6 U7 O7


•

Sx = General status bit for channels 0 through 5 and CJC sensors (S6 and S7). This bit is set (1) when an error (over-range, under-range, open-circuit, or input data not valid) exists for that channel. An input data not valid condition is determined by the user program. This condition occurs when the first analog-to-digital conversion is still in progress, after a new configuration has been sent to the module.

•

OCx = Open circuit detection bits indicate an open input circuit on channels 0 through 5 (OC0 through OC5) and on CJC sensors CJC0

(OC6) and CJC1 (OC7). The bit is set (1) when an open-circuit condition exists.

•

Ux = Under-range flag bits for channels 0 through 5 and the CJC sensors (U6 and U7). For thermocouple inputs, the under-range bit is set when a temperature measurement is below the normal operating range for a given thermocouple type. For millivolt inputs, the under-range bit indicates a voltage that is below the normal operating range. These bits can be used in the control program for error detection.

•

Ox = Over-range flag bits for channels 0 through 5 and the CRC sensors (O6 and O7). For thermocouple inputs, the over-range bit is set when a temperature measurement is above the normal operating range for a given thermocouple type. For millivolt inputs, the over-range bit indicates a voltage that is above the normal operating range. These bits can be used in the control program for error detection.



I/O Addressing

Addressing Details

The I/O addressing scheme and examples are shown below.

Slot Number

(1)

Data File Number

Word

File Type

Input (I) or Output (O)

Xd:s.w/b

Bit

Slot Delimiter

Word Delimiter

Bit Delimiter

(1) I/O located on the controller (embedded I/O) is slot 0.

I/O added to the controller (expansion I/O) begins with slot 1.

Format Explanation

Od:s.w/b X

File Type

Id:s.w/b

: d

Data File Number (optional)

Input (I) or Output (O)

0 = output, 1 = input

Slot delimiter (optional, not required for Data Files 2 to 255)

s

/

.

w b

Slot number (decimal) Embedded I/O: slot 0

Expansion I/O:

•

•

slots 1 to 6 for MicroLogix 1200 (See page 1-3 for an illustration.)

slots 1 to 8 for MicroLogix 1500 (See page 1-7 for an illustration.)

Word delimiter. Required only if a word number is necessary as noted below.

Word number Required to read/write words, or if the discrete bit number is above 15.

Range: 0 to 255

Bit delimiter

Bit number 0 to 15

Addressing Examples

Addressing Level

Bit Addressing

Word Addressing

Example Address

(1)

O:0/4

(2)

O:2/7

(2)

I:1/4

(2)

I:0/15

(2)

O:1.0

I:7.3

I:3.1

Slot

Output Slot 0 (Embedded I/O)

Output Slot 2 (Expansion I/O)

Input Slot 1 (Expansion I/O)

Input Slot 0 (Embedded I/O)

Output Slot 1 (Expansion I/O)



(1) The optional Data File Number is not shown in these examples.

(2) A word delimiter and number are not shown. Therefore, the address refers to word 0.

Word

word 0 word 0 word 0 word 0 word 0 word 3 word 1

Bit

output bit 4 output bit 7 input bit 4 input bit 15



I/O Forcing

Input Filtering

I/O forcing is the ability to override the actual status of the I/O at the user’s discretion.

Input Forcing

When an input is forced, the value in the input data file is set to a user-defined state. For discrete inputs, you can force an input “on” or

“off”. When an input is forced, it no longer reflects the state of the physical input or the input LED. For embedded inputs, the controller reacts as if the force is applied to the physical input terminal.

NOTE

When an input is forced, it has no effect on the input device connected to the controller.

Output Forcing

When an output is forced, the controller overrides the status of the control program, and sets the output to the user-defined state. Discrete outputs can be forced “on” or “off”. The value in the output file is unaffected by the force. It maintains the state determined by the logic in the control program. However, the state of the physical output and the output LED will be set to the forced state.

NOTE

If you force an output controlled by an executing PTO or

PWM function, an instruction error is generated.

The MicroLogix 1200 and 1500 controllers allow users to configure groups of DC inputs for high-speed or normal operation. Users can configure each input group’s response time. A configurable filter determines how long the input signal must be “on” or “off” before the controller recognizes the signal. The higher the value, the longer it takes for the input state to be recognized by the controller. Higher values provide more filtering, and are used in electrically noisy environments. Lower values provide less filtering, and are used to detect fast or narrow pulses. You typically set the filters to a lower value when using high-speed counters, latching inputs, and input interrupts.

Input filtering is configured using RSLogix 500 programming software. To configure the filters using RSLogix 500:

1. Open the “Controller” folder.

2. Open the “I/O Configuration” folder.

3. Open slot 0 (controller).

4. Select the “embedded I/O configuration” tab.


Latching Inputs


The input groups are pre-arranged. Simply select the filter time you require for each input group. You can apply a unique input filter setting to each of the input groups:

Controller MicroLogix 1200

Input Groups

•

0 and 1

•

•

2 and 3

4 and above

MicroLogix 1500

•

•

•

•

•

0 and 1

2 and 3

4 and 5

6 and 7

8 and above

The minimum and maximum response times associated with each input filter setting can be found in your controller’s User Manual.

The MicroLogix 1200 and 1500 controllers provide the ability to individually configure inputs to be latching inputs (sometimes referred to as pulse catching inputs). A latching input is an input that captures a very fast pulse and holds it for a single controller scan. The pulse width that can be captured is dependent upon the input filtering selected for that input.

The following inputs can be configured as latching inputs:

Controller

DC Inputs

MicroLogix 1200

0 through 3

MicroLogix 1500

0 through 7

You enable this feature with RSLogix 500 programming software. With an open project:



3. Open slot 0 (controller).

4. Select the “embedded I/O configuration” tab.

5. Select the mask bits for the inputs that you want to operate as latching inputs.

6. Select the state for the latching inputs. The controller can detect both

“on” (rising edge) and “off” (falling edge) pulses, depending upon the configuration selected in the programming software.

The following information is provided for a controller looking for an “on” pulse. When an external signal is detected “on”, the controller “latches” this event. In general, at the next input scan following this event, the input image point is turned “on” and remains “on” for the next controller scan. It is then set to “off” at the next input scan. The following figures help demonstrate this.



Rising Edge Behavior - Example 1

Input

Scan

Scan Number (X)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+1)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+2)

Ladder

Scan

Output

Scan

External

Input

Latched

Status

Input File

Value

Rising Edge Behavior - Example 2

Input

Scan

Scan Number (X)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+1)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+2)

Ladder

Scan

Output

Scan

External

Input

Latched

Status

NOTE

Input File

Value

The “gray” area of the Latched Status waveform is the input filter delay.

IMPORTANT

The input file value does not represent the external input when the input is configured for latching behavior. When configured for rising edge behavior, the input file value is normally “off” (“on” for 1 scan when a rising edge pulse is detected).

The previous examples demonstrate rising edge behavior. Falling edge behavior operates exactly the same way with these exceptions:

•

The detection is on the “falling edge” of the external input.

•

The input image is normally “on” (1), and changes to “off” (0) for one scan.



Falling Edge Behavior - Example 1

Scan Number (X)

Input

Scan

Ladder

Scan

Output

Scan

Scan Number (X+1)

Input

Scan

Ladder

Scan

Output

Scan

Scan Number (X+2)

Input

Scan

Ladder

Scan

Output

Scan

Scan Number (X+3)

Input

Scan

Ladder

Scan

Output

Scan

External

Input

Latched

Status

Input File

Value

Falling Edge Behavior - Example 2

Input

Scan

Scan Number (X)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+1)

Ladder

Scan

Output

Scan

Input

Scan

Scan Number (X+2)

Ladder

Scan

Output

Scan

External

Input

Latched

Status

Input File

Value

NOTE

The “gray” area of the Latched Status waveform is the input filter delay.

IMPORTANT

The input file value does not represent the external input when the input is configured for latching behavior. When configured for falling edge behavior, the input file value is normally “on” (“off” for 1 scan when a falling edge pulse is detected).



Configuring Expansion

I/O Using RSLogix 500

Expansion I/O must be configured for use with the controller. Configuring expansion I/O can be done either manually, or automatically. Using

RSLogix 500:



3. For manual configuration, drag the Compact I/O module to the slot.

For automatic configuration, you must have the controller connected to the computer (either directly or over a network). Click the “Read

I/O Config” button on the I/O configuration screen. RSLogix 500 will read the existing configuration of the controller’s I/O.

Some I/O modules support or require configuration. To configure a specific module, double-click on the module, an I/O configuration screen will open that is specific to the module.


Chapter

2

Controller Memory and File Types

This chapter describes controller memory and the types of files used by the

MicroLogix 1200 and MicroLogix 1500 controllers. The chapter is organized as follows:

•

Controller Memory on page 2-2

•

Data Files on page 2-5

•

Protecting Data Files During Download on page 2-6

•

Static File Protection on page 2-8

•

Password Protection on page 2-9

•

Clearing the Controller Memory on page 2-10

•

Allow Future Access Setting (OEM Lock) on page 2-10

1 Publication 1762-RM001C-EN-P

2-2 Controller Memory and File Types

Controller Memory

NOTE

File Structure

MicroLogix 1200 and 1500 user memory is comprised of Data Files, Function

Files, and Program Files (and B-Ram files for the MicroLogix 1500 1764-LRP processor). Function Files are exclusive to the MicroLogix 1200 and 1500 controllers; they are not available in the MicroLogix 1000 or SLC controllers.

The file types shown below for data files 3 through 7 are the default filetypes for those file numbers and cannot be changed. Data files 9 through 255 can be added to your program to operate as bit, timer, counter, control, integer, string, long word, message, or PID files.

Data

Files

Function

Files

Program

Files

Specialty

(3)

Files

0

1

2 to 255

0

1

2

3

4

5

6

0

1

2

3 to 255

7

9 to 255

B Bit

T Timer

C Counter

R Control

N Integer

ST String

(1)

L Long Word

MG Message

PD PID

HSC

PTO

(2)

PWM

(2)

STI

EII

RTC

TPI

MMI

DAT

(2)

BHI

CS

IOS

(1) The string file is available in MicroLogix 1200 controllers and MicroLogix 1500 1764-LSP Series B and 1764-LRP processors.

(2) The DAT files are only used in MicroLogix 1500 controllers. The PTO and PWM files are only used in MicroLogix 1200 and 1500 BXB units.

(3) Specialty files for Data Logging are only used by the MicroLogix 1500 1764-LRP processor.


Controller Memory and File Types 2-3

User Memory

User memory is the amount of storage available to a user for storing ladder logic, data table files, I/O configuration, etc., in the controller.

User data files consist of the system status file, I/O image files, and all other user-creatable data files (bit, timer, counter, control, integer, string, long word, MSG, and PID).

A word is defined as a unit of memory in the controller. The amount of memory available to the user for data files and program files is measured in user words. Memory consumption is allocated as follows:

•

For data files, a word is the equivalent of 16 bits of memory. For example,

– 1 integer data file element = 1 user word

– 1 long word file element = 2 user words

– 1 timer data file element = 3 user words

•

For program files, a word is the equivalent of a ladder instruction with one operand. For example

(1)

,

– 1 XIC instruction, which has 1 operand, consumes 1 user word

– 1 EQU instruction, which has 2 operands, consumes 2 user words

– 1 ADD instruction, which has 3 operands, consumes 3 user words

•

Function files do not consume user memory.

NOTE

Although the controller allows up to 256 elements in a file, it may not actually be possible to create a file with that many elements due to the user memory size in the controller.

MicroLogix 1200 User Memory

The MicroLogix 1200 controller supports 6K of memory. Memory can be used for program files and data files. The maximum data memory usage is

2K words as shown below.

2.0K

0.5K

0K

0K

Program Words

4K 4.3K

See MicroLogix 1200 Memory Usage and Instruction Execution Time on page A-1 to find the memory usage for specific instructions.

(1) These are approximate values. For actual memory usage, see the tables in Appendix A and B of this manual.



MicroLogix 1500 User Memory

MicroLogix 1500, 1764-LSP Processor

The 1764-LSP processor supports over 7K of memory. Memory can be used for program files and data files. The maximum data memory usage is 4K words as shown below.

4.0K

0.5K

0K

0K

Program Words

3.65K

4.35K

MicroLogix 1500, 1764-LRP Processor

The 1764-LRP processor supports 12K of memory. Memory can be used for program files and data files. The maximum data memory usage is 4K words as shown below.

4.0K


0.5K

0K

0K

8K 8.7K

Program Words

IMPORTANT

For the MicroLogix 1500, the maximum file size of any single ladder file is 6.4K words. You can utilize the entire programming space by using multiple ladder files through the use of subroutines.

The 1764-LRP processor also supports 48K of battery backed memory for

Data Logging Operations. See Chapter 22 for Data Logging information.

See MicroLogix 1500 Memory Usage and Instruction Execution Time on page B-1 to find the memory usage for specific instructions.


Data Files

Data files store numeric information, including I/O, status, and other data associated with the instructions used in ladder subroutines. The data file types are:

File Name File

Identifier

File

Number

(1)

0

Words per

Element

File Description

Output File

Input File

Status File

Bit File

Timer File

Counter File

Control File

Integer File

String File

I

O

S

B

T

C

R

N

ST

1

2

3, 9 to 255

4, 9 to 255

5, 9 to 255

6, 9 to 255

7, 9 to 255

9 to 255

1

1

1

1

3

3

3

1

42

The Output File stores the values that are written to the physical outputs during the Output Scan.

The Input File stores the values that are read from the physical inputs during the Input Scan.

The contents of the Status File are determined by the functions which

utilize the Status File. See System Status File on page C-1 for a detailed

description.

The Bit File is a general purpose file typically used for bit logic.

The Timer File is used for maintaining timing information for ladder logic

timing instructions. See Timer and Counter Instructions on page 8-1 for

instruction information.

The Counter File is used for maintaining counting information for ladder

logic counting instructions. See Timer and Counter Instructions on page

8-1 for instruction information.

The Control Data file is used for maintaining length and position information for various ladder logic instructions.

The Integer File is a general purpose file consisting of 16-bit, signed integer data words.

The String File is a file that stores ASCII characters.

(Not valid for MicroLogix 1500 1764-LSP Series A Processors.)

Long Word File

Message File

L

MG

9 to 255

9 to 255

2

25

The Long Word File is a general purpose file consisting of 32-bit, signed integer data words.

The Message File is associated with the MSG instruction. See

Communications Instructions on page 21-1 for information on the MSG

instruction.

PID File PD 9 to 255 23

The PID File is associated with the PID instruction. See Process Control

Instruction on page 19-1 for more information.

(1) File Number in BOLD is the default. Additional data files of that type can be configured using the remaining numbers.



Protecting Data Files

During Download

Data File Download Protection

Once a user program is in the controller, there may be a need to update the ladder logic and download it to the controller without destroying user-configured variables in one or more data files in the controller. This situation can occur when an application needs to be updated, but the data that is relevant to the installation needs to remain intact.

This capability is referred to as Data File Download Protection. The protection feature operates when:

•

A User Program is downloaded via programming software

•

A User Program is downloaded from a Memory Module

Setting Download File Protection

Download File Protection can be applied to the following data file types:

•

Output (O)

•

Input (I)

•

Binary (B)

•

Timer (T)

•

Counter (C)

•

Control (R)

•

Integer (N)

•

String (ST)

•

Long Word (L)

•

Proportional Integral Derivative (PD)

•

Message (MG)

NOTE

The data in the Status File cannot be protected.



Access the Download Data File Protect feature using RSLogix 500 programming software. For each data file you want protected, check the

Memory Module/Download item within the protection box in the Data File Properties screen as shown in this illustration. To access this screen, right mouse click on the desired data file.

User Program Transfer Requirements

Data File Download Protection only operates when the following conditions are met during a User Program or Memory Module download to the controller:

•

The controller contains protected data files.

•

The program being downloaded has the same number of protected data files as the program currently in the controller.

•

All protected data file numbers, types, and sizes (number of elements) currently in the controller exactly match that of the program being downloaded to the controller.

If all of these conditions are met, the controller will not write over any data file in the controller that is configured as Download Protected.

If any of these conditions are not met, the entire User Program is transferred to the controller. Additionally, if the program in the controller contains protected files, the Data Protection Lost indicator (S:36/10) is set to indicate that protected data has been lost. For example, a control program with protected files is transferred to the controller. The original program did not have protected files or the files did not match. The data protection lost indicator (S:36/10) is then set. The data protection lost indicator represents that the protected files within the controller have had values downloaded and the user application may need to be re-configured.

NOTE

The controller will not clear the Data Protection Lost indicator. It is up to the user to clear this bit.



Static File Protection

When a data file is Static File Protected, the values contained in it cannot be changed via communications, except during a program download to the controller.

Using Static File Protection with Data File Download Protection

Static File Protection and Data File Download Protection can be used in combination with any MicroLogix 1200 Controller Series B and higher, and MicroLogix 1500 Processor Series B and higher.

Setting Static File Protection

Static File Protection can be applied to the following data file types:

•

Output (O)

•

Input (I)

•

Status (S)

•

Binary (B)

•

Timer (T)

•

Counter (C)

•

Control (R)

•

Integer (N)

•

String (ST)

•

Long Word (L)

•

Proportional Integral Derivative (PD)

•

Message (MG)

Access the Static File Protect feature using

RSLogix 500 programming software. For each data file you want protected, select the Static protection in the Data File Properties screen as shown in this illustration. To access this screen, right mouse click on the desired data file.

NOTE

Statically protected files are not protected from MSG instruction writes.



Password Protection

MicroLogix controllers have a built-in security system, based on numeric passwords. Controller passwords consist of up to 10 digits (0-9). Each controller program may contain two passwords, the Password and the

Master Password.

Passwords restrict access to the controller. The Master Password takes precedence over the Password. The idea is that all controllers in a project would have different Passwords, but the same Master Password, allowing access to all controllers for supervisory or maintenance purposes.

You can establish, change, or delete a password by using the Controller

Properties dialog box. It is not necessary to use passwords, but if used, a master password is ignored unless a password is also used.

NOTE

If a password is lost or forgotten, there is no way to bypass the password to recover the program. The only option is to clear the controller’s memory.

If the Memory Module User Program has the “Load Always” functionality enabled, and the controller User Program has a password specified, the controller compares the passwords before transferring the User Program from the Memory Module to the controller. If the passwords do not match, the User Program is not transferred and the program mismatch bit is set

(S:5/9).



Clearing the Controller

Memory

Allow Future Access

Setting (OEM Lock)

If you are locked out because you do not have the password for the controller, you can clear the controller memory and download a new User

Program.

You can clear the memory when the programming software prompts you for a System or Master Password to go on-line with the controller. To do so:

1. Enter 65257636 (the telephone keypad equivalent of MLCLRMEM,

MicroLogix Clear Memory).

2. When the Programming Software detects this number has been entered, it asks if you want to clear the memory in the controller.

3. If you reply “yes” to this prompt, the programming software instructs the controller to clear Program memory.

The controller supports a feature which allows you to select if future access to the User Program should be allowed or disallowed after it has been transferred to the controller. This type of protection is particularly useful to an OEM (original equipment manufacturer) who develops an application and then distributes the application via a memory module or within a controller.

The Allow Future Access setting is found in the Controller Properties window as shown below.


When Allow Future Access is deselected, the controller requires that the

User Program in the controller is the same as the one in the programming device. If the programming device does not have a matching copy of the

User Program, access to the User Program in the controller is denied. To access the User Program, clear controller memory and reload the program.

NOTE

Functions such as change mode, clear memory, restore program, and transfer memory module are allowed regardless of this selection.

Controller passwords are not associated with the Allow

Future Access setting.

Chapter

3

Function Files

This chapter describes controller function files. The chapter is organized as follows:

•

Overview on page 3-2

•

Real-Time Clock Function File on page 3-3

•

Trim Pot Information Function File on page 3-5

•

Memory Module Information Function File on page 3-6

•

DAT Function File (MicroLogix 1500 only) on page 3-9

•

Base Hardware Information Function File on page 3-12

•

Communications Status File on page 3-13

•

Input/Output Status File on page 3-18


3-2 Function Files

Overview

Table 3.1 Function Files

File Name

High-Speed Counter

File

Identifier

HSC

Pulse Train Output

(MicroLogix 1200 and 1500

BXB units only.)

PTO

Pulse Width Modulation

(MicroLogix 1200 and 1500

BXB units only.)

PWM

Selectable Timed Interrupt

STI

Event Input Interrupt

Real-Time Clock

Trim Pot Information

Memory Module

Information

Data Access Tool

Information

(MicroLogix 1500 only.)

MMI

DAT

Base Hardware Information BHI

Communications Status

File

I/O Status File

EII

RTC

TPI

CS

IOS

Function Files are one of the three primary file structures within the

MicroLogix 1200 and MicroLogix 1500 controllers (Program Files and Data

Files are the others). Function Files provide an efficient and logical interface to controller resources. Controller resources are resident

(permanent) features such as the Real-Time Clock and High-Speed

Counter. The features are available to the control program through either instructions that are dedicated to a specific function file, or via standard instructions such as MOV and ADD. The Function File types are:


This file type is associated with the High-Speed Counter function. See Using the

High-Speed Counter on page 5-1 for more information.

This file type is associated with the Pulse Train Output Instruction. See Pulse Train Outputs

(PTO) Function File on page 6-6 for more information.

This file type is associated with the Pulse Width Modulation instruction. See Pulse Width

Modulation (PWM) Function File on page 6-19 for more information.

This file type is associated with the Selectable Timed Interrupt function. See Using the

Selectable Timed Interrupt (STI) Function File on page 18-12 for more information.

This file type is associated with the Event Input Interrupt instruction. See Using the Event

Input Interrupt (EII) Function File on page 18-17 for more information.

This file type is associated with the Real-Time Clock (time of day) function. See Real-Time

Clock Function File on page 3-3 for more information.

This file type contains information about the Trim Pots. See Trim Pot Information Function

File on page 3-5 for more information.

This file type contains information about the Memory Module. See Memory Module

Information Function File on page 3-6 for more information.

This file type contains information about the Data Access Terminal. See DAT Function File

(MicroLogix 1500 only) on page 3-9 for more information.

This file type contains information about the controller’s hardware. See Base Hardware

Information Function File on page 3-12 for the file structure.

This file type contains information about the Communications with the controller. See

Communications Status File on page 3-13 for the file structure.

This file type contains information about the controller I/O. See Input/Output Status File on page 3-18 for the file structure.


Real-Time Clock

Function File

Function Files 3-3

The real-time clock provides year, month, day of month, day of week, hour, minute, and second information to the Real-Time Clock (RTC)

Function File in the controller. The programming screen is shown below:

The parameters and their valid ranges are shown in the table below.

Table 3.2 Real-Time Clock Function File

Feature Address Data Format Range Type

YR - RTC Year

MON - RTC Month

DAY - RTC Day of Month

HR - RTC Hours

MIN - RTC Minutes

SEC - RTC Seconds

DOW - RTC Day of Week

DS - Disabled

BL - RTC Battery Low

RTC:0.YR

word

RTC:0.MON

word

RTC:0.DAY

RTC:0.HR

word word

RTC:0.MIN

RTC:0.SEC

word word

RTC:0.DOW

word

RTC:0/DS binary

RTC:0/BL binary

1998 to 2097

1 to 12

1 to 31

0 to 23 (military time)

0 to 59

0 to 59

0 to 6 (Sunday to Saturday)

0 or 1

0 or 1 status status status status status status status status status

User Program

Access

read-only read-only read-only read-only read-only read-only read-only read-only read-only

The following table indicates the expected accuracy of the real-time clock for various temperatures.

Table 3.3 Real-Time Clock Accuracy at Various Temperatures

Ambient Temperature

0°C (+32°F)

+25°C (+77°F)

+40°C (+104°F)

+55°C (+131°F)

Accuracy

(1)

+34 to -70 seconds/month



-133 to -237 seconds/month

(1) These numbers are worst case values over a 31 day month.



Writing Data to the Real-Time Clock

When valid data is sent to the real-time clock from the programming device or another controller, the new values take effect immediately. In

RSLogix 500, click on Set Date & Time in the RTC Function File screen to set the RTC time to the current time on your PC.

NOTE

You can use a MSG instruction to write RTC data from one controller to another to synchronize time. To send (write)

RTC data, use RTC:0 as the source. This feature not

available with the Series A controllers.

The real-time clock does not allow you to load or store invalid date or time data.

NOTE

Use the Disable Clock button in your programming device to disable the real-time clock before storing a module.

This decreases the drain on the battery during storage.

RTC Battery Operation

The real-time clock has an internal battery that is not replaceable. The

RTC Function File features a battery low indicator bit (RTC:0/BL), which represents the status of the RTC battery. When the battery is low, the indicator bit is set (1). This means that the battery will fail in less than 14 days, and the real-time clock module needs to be replaced. When the battery low indicator bit is clear (0), the battery level is acceptable, or a real-time clock is not attached.

ATTENTION

!

Operating with a low battery indication for more than 14 days may result in invalid RTC data if power is removed from the controller.

Table 3.4 RTC Battery Life Expectancy

Battery State Temperature

Operating

Storage

0°C to +40°C (+32°F to +104°F)

-40°C to +25°C (-40°F to +77°F)

Time Duration

5 years

(1)

5 years minimum

+26°C to +60°C (+79°F to +140°F) 3 years minimum

(1) The operating life of the battery is based on 6 months of storage time before the real-time clock is used.



Trim Pot Information

Function File

The composition of the Trim Pot Information (TPI) Function File is described below.

Table 3.5 Trim Pot Function File

Data Address

TPD Data O

TPD Data 1

TP0 Error Code TPI:0.ER

TP1 Error Code

TPI:0.POT0

TPI:0.POT1

Data Format

Word

(16-bit integer)

Word

(16-bit integer)

0 - 250

0 - 250

Word (bits 0 to 7) 0 - 3

Status

Status

Status

Read Only

Read Only

Read Only

Word (bits 8 to 15)

Range Type User Program

Access

The data resident in TPI:0.POT0 represents the position of trim pot 0. The data resident in TPI:0.POT1 corresponds to the position of trim pot 1. The valid data range for both is from 0 (counterclockwise) to 250 (clockwise).

Error Conditions

If the controller detects a problem with either trim pot, the last values read remain in the data location, and an error code is put in the error code byte of the TPI file for whichever trim pot had the problem. Once the controller can access the trim pot hardware, the error code is cleared.

The error codes are described in the table below.

Table 3.6 Trim Pot Error Codes

1

2

Error Code Description

0 Trim pot data is valid.

3

Trim pot subsystem detected, but data is invalid.

Trim pot subsystem did not initialize.

Trim pot subsystem failure.



Memory Module

Information Function

File

The controller has a Memory Module Information (MMI) File which is updated with data from the attached memory module. At power-up or on detection of a memory module being inserted, the catalog number, series, revision, and type (memory module and/or real-time clock) are identified and written to the MMI file in the user program. If a memory module and/ or real-time clock is not attached, zeros are written to the MMI file.

The memory module function file programming screen is shown below:


The parameters and their valid ranges are shown in the table below.

Table 3.7 MMI Function File Parameters

Feature Address Data Format Type

FT - Functionality Type MMI:0.FT

MP - Module Present MMI:0/MP

WP - Write Protect

FO - Fault Override

MMI:0/WP

MMI:0/FO

LPC - Program Compare MMI:0/LPC

LE - Load On Error MMI:0/LE

LA - Load Always

MB - Mode Behavior

MMI:0/LA

MMI:0/MB word (INT) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) status status control control control control control control

User Program

Access

read-only read-only read-only read-only read-only read-only read-only read-only

FT - Functionality Type

The LSB of this word identifies the type of module installed:

•

1 = Memory Module

•

2 = Real-Time Clock Module

•

3 = Memory and Real-Time Clock Module


MP - Module Present

The MP (Module Present) bit can be used in the user program to determine when a memory module is present on the controller. This bit is updated once per scan, provided the memory module is first recognized by the controller. To be recognized by the controller, the memory module must be installed prior to power-up or when the controller is in a non-executing mode. If a memory module is installed when the controller is in an executing mode, it is not recognized. If a recognized memory module is removed during an executing mode, this bit is cleared (0) at the end of the next ladder scan.

WP - Write Protect

When the WP (Write Protect) bit is set (1), the module is write-protected and the user program and data within the memory module cannot be overwritten

IMPORTANT

Once the WP bit is set (1), it cannot be cleared. Only set this bit if you want the contents of the memory module to become permanent.

FO - Fault Override

The FO (Fault Override) bit represents the status of the fault override setting of the program stored in the memory module. It enables you to determine the value of the FO bit without actually loading the program from the memory module.

IMPORTANT

The memory module fault override selection in the

Memory Module Information (MMI) file does not determine the controller’s operation. It merely displays the setting of the user program’s Fault Override bit (S:1/8) in the memory module.

See Fault Override At Power-Up on page C-5 for more information.

LPC - Load Program Compare

The LPC (Load Program Compare) bit shows the status of the load program compare selection in the memory module’s user program status file. It enables you to determine the value without actually loading the user program from the memory module.

See Memory Module Program Compare on page C-9 for more

information.



LE - Load on Error

The LE (Load on Error) bit represents the status of the load on error setting in the program stored in the memory module. It enables you to determine the value of the selection without actually loading the user program from the memory module.

See Load Memory Module On Error Or Default Program on page C-5 for

more information.

LA - Load Always

The LA (Load Always) bit represents the status of the load always setting in the program stored in the memory module. It enables you to determine the value of the selection without actually loading the user program from the memory module.

See Load Memory Module Always on page C-6 for more information.

MB - Mode Behavior

The MB (Mode Behavior) bit represents the status of the mode behavior setting in the program stored in the memory module. It enables you to determine the value of the selection without actually loading the user program from the memory module.

See Power-Up Mode Behavior on page C-6 for more information.



DAT Function File

(MicroLogix 1500 only)

Data Access Tool (DAT) configuration is stored in the processor in a specialized configuration file called the DAT Function File. The DAT

Function File, which is part of the user’s control program, is shown below.

The DAT function file contains the Target Integer File, the Target Bit File, and the Power Save Timeout parameter. These three parameters are described in the table below.

Feature

Target Integer File

Target Bit File

Power Save Timeout

Address

DAT:0.TIF

DAT:0.TBF

DAT:0.PST

Data Format Type

Word (int)

Word (int)

Word (int)

Control

Control

Control

User Program

Access

Read Only

Read Only

Read Only

Target Integer File (TIF)

The value stored in the TIF location identifies the integer file with which the DAT will interface. The DAT can read or write to any valid integer file within the controller. Valid integer files are N3 through N255. When the

DAT reads a valid integer file number, it can access the first 48 elements (0 to 47) of the specified file on its display screen. The next 48 bits (words

48 to 50) are used to define the read-only or read/write privileges for the

48 elements.

The only integer file that the DAT interfaces with is the file specified in the

TIF location. The TIF location can only be changed by a program download.



10

11

12

13

8

9

6

7

14

15

4

5

2

3

0

1

Element

Number

IMPORTANT

Use your programming software to ensure that the integer file you specify in the TIF location, as well as the appropriate number of elements, exist in the controller’s user program.

The example table below shows a DAT configured to use integer file number 50 (DAT:0.TIF = 50).

N50:6

N50:7

N50:8

N50:9

N50:10

N50:11

N50:12

N50:13

N50:14

N50:15

Data Address Protection Bit Element

Number

N50:0

N50:1

N50:48/0

N50:48/1

16

17

N50:2

N50:3

N50:4

N50:5

N50:48/2

N50:48/3

N50:48/4

N50:48/5

18

19

20

21

N50:48/6

N50:48/7

N50:48/8

N50:48/9

N50:48/10

N50:48/11

N50:48/12

N50:48/13

N50:48/14

N50:48/15

26

27

28

29

22

23

24

25

30

31

N50:22

N50:23

N50:24

N50:25

N50:26

N50:27

N50:28

N50:29

N50:30

N50:31

Data Address Protection Bit Element

Number

N50:16

N50:17

N50:49/0

N50:49/1

32

33

N50:18

N50:19

N50:20

N50:21

N50:49/2

N50:49/3

N50:49/4

N50:49/5

34

35

36

37

N50:49/6

N50:49/7

N50:49/8

N50:49/9

N50:49/10

N50:49/11

N50:49/12

N50:49/13

N50:49/14

N50:49/15

42

43

44

45

38

39

40

41

46

47

Data Address Protection Bit

N50:40

N50:41

N50:42

N50:43

N50:44

N50:45

N50:46

N50:47

N50:32

N50:33

N50:34

N50:35

N50:36

N50:37

N50:38

N50:39

N50:50/0

N50:50/1

N50:50/2

N50:50/3

N50:50/4

N50:50/5

N50:50/6

N50:50/7

N50:50/8

N50:50/9

N50:50/10

N50:50/11

N50:50/12

N50:50/13

N50:50/14

N50:50/15

The element number displayed on the DAT corresponds to the data register as illustrated in the table. The protection bit defines whether the data is read/write or read-only. When the protection bit is set (1), the corresponding data address is considered read-only by the DAT. The

Protected LED illuminates whenever a read-only element is active on the

DAT display. When the protection bit is clear (0) or the protection bit does not exist, the Protected LED is off and the data within the corresponding address is editable from the DAT keypad.

IMPORTANT

Although the DAT does not allow protected data to be changed from its keypad, the control program or other communication devices do have access to this data.

Protection bits do not provide any overwrite protection to data within the target integer file. It is entirely the user’s responsibility to ensure that data is not inadvertently overwritten.

NOTE

•

Remaining addresses within the target file can be used without restrictions (addresses N50:51 and above, in this example).

•

The DAT always starts at word 0 of a data file. It cannot start at any other address within the file.



Target Bit File (TBF)

The value stored in the TBF location identifies the bit file with which the

DAT will interface. The DAT can read or write to any valid bit file within the controller. Valid bit files are B3 through B255. When the DAT reads a valid bit file number, it can access the first 48 bits (0 to 47) of the specified file on its display screen. The next 48 bits (48 to 95) are used to define the read-only or read/write privileges for the first 48 bits.

The only bit file that the DAT interfaces with is the file specified in the

TBF location. The TBF location can only be changed by a program download.

IMPORTANT

Use your programming software to ensure that the bit file you specify in the TBF location, as well as the appropriate number of elements, exist in the MicroLogix 1500 user program.

The example table below shows how the DAT uses the configuration information with bit file number 51 (DAT:0.TBF=51).

11

12

13

14

15

7

8

9

10

5

6

3

4

1

2

Bit Number Data Address Protection Bit Bit Number Data Address Protection Bit Bit Number Data Address Protection Bit

0 B51/0 B51/48 16 B51/16 B51/64 32 B51/32 B51/80

B51/1

B51/2

B51/49

B51/50

17

18

B51/17

B51/18

B51/65

B51/66

33

34

B51/33

B51/34

B51/81

B51/82

B51/3

B51/4

B51/5

B51/6

B51/51

B51/52

B51/53

B51/54

19

20

21

22

B51/19

B51/20

B51/21

B51/22

B51/67

B51/68

B51/69

B51/70

35

36

37

38

B51/35

B51/36

B51/37

B51/38

B51/83

B51/84

B51/85

B51/86

B51/7

B51/8

B51/9

B51/10

B51/11

B51/12

B51/13

B51/14

B51/15

B51/55

B51/56

B51/57

B51/58

B51/59

B51/60

B51/61

B51/62

B51/63

23

24

25

26

27

28

29

30

31

B51/23

B51/24

B51/25

B51/26

B51/27

B51/28

B51/29

B51/30

B51/31

B51/71

B51/72

B51/73

B51/74

B51/75

B51/76

B51/77

B51/78

B51/79

39

40

41

42

43

44

45

46

47

B51/39

B51/40

B51/41

B51/42

B51/43

B51/44

B51/45

B51/46

B51/47

B51/87

B51/88

B51/89

B51/90

B51/91

B51/92

B51/93

B51/94

B51/95

The bit number displayed on the DAT corresponds to the data bit as illustrated in the table. The protection bit defines whether the data is editable or read-only. When the protection bit is set (1), the corresponding data address is considered read-only by the DAT. The

Protected LED illuminates whenever a read-only element is active on the

DAT display. When the protection bit is clear (0) or the protection bit does not exist, the Protected LED is off and the data within the corresponding address is editable from the DAT keypad.



IMPORTANT

Although the DAT does not allow protected data to be changed from its keypad, the control program or other communication devices do have access to this data.

Protection bits do not provide any overwrite protection to data within the target bit file. It is entirely the user’s responsibility to ensure that data is not inadvertently overwritten.

NOTE

•

Remaining addresses within the target file can be used without restrictions (addresses B51/96 and above, in this example).

•

The DAT always starts at bit 0 of a data file. It cannot start at any other address within the file.

Base Hardware

Information Function

File

The base hardware information (BHI) file is a read-only file that contains a description of the MicroLogix 1200 Controller or the MicroLogix 1500

Base Unit.

Table 3.8 Base Hardware Information Function File (BHI)

Address

BHI:0.CN

BHI:0.SRS

BHI:0.REV

BHI:0.FT

Description

CN - Catalog Number

SRS - Series

REV - Revision

FT - Functionality Type



Communications Status

File

The Communications Status (CS) File is a read-only file that contains information on how the controller communication parameters are configured and status information on communications activity.

The communications status file uses:

Table 3.9 Communications Status File Size

Controller

MicroLogix 1500 1764-LSP Series A Processor

Number of Word Elements

44 1-word elements

MicroLogix 1200

MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors

71 1-word elements

There is one communications Status file for each communications port.

Communications Status File CS0 corresponds to Channel 0 on the controller. Communications Status File CS1 corresponds to Channel 1 on the 1764-LRP processor.

NOTE

You can use the Communications Status File information as a troubleshooting tool for communications issues.

The data file is structured as:

Table 3.10 Communications Status File

Word Description Applies to Controller

0 to 5 General Channel Status Block

6 to 22 DLL Diagnostic Counters Block

MicroLogix 1200 and 1500

MicroLogix 1200 and 1500

23 to 42 DLL Active Node Table Block MicroLogix 1200 and 1500

words 43 to 70 when using DF1 Full-Duplex, DF1 Half-Duplex, DH-485, or ASCII

(1)

:

MicroLogix 1200 and 1500 43 End of List Category Identifier Code

(always 0)

43 to 70 Reserved

•

•

MicroLogix 1200

MicroLogix 1500 1764-LSP

Series B and 1764-LRP

Processors

words 43 to 70 when using Modbus RTU Slave:

43 to 69 Modbus Slave Diagnostic Counters Block

•

MicroLogix 1200

•



Processors

70 End of List Category Identifier Code

(always 0)

•

•

MicroLogix 1200



Processors

(1) ASCII can only be used with the MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors.

Details on Page

3-14

3-14

3-17

--

--

3-18

--

The following tables show the details of each block in the

Communications Status File.



Table 3.11 General Channel Status Block

2

3

4

Word Bit

0

1

-

-

-

-

0

5

1

Description

Communications Channel General Status Information Category Identifier Code

Length

Format Code

Communications Configuration Error Code

ICP – Incoming Command Pending Bit

This bit is set (1) when the controller determines that another device has requested information from this controller.

Once the request has been satisfied, the bit is cleared (0).

MRP – Incoming Message Reply Pending Bit

This bit is set (1) when the controller determines that another device has supplied the information requested by a MSG instruction executed by this controller. When the appropriate MSG instruction is serviced (during end-of-scan, SVC, or

REF), this bit is cleared (0).

2

3

MCP – Outgoing Message Command Pending Bit

This bit is set (1) when the controller has one or more MSG instructions enabled and in the communication queue. This bit is cleared (0) when the queue is empty.

SSB – Selection Status Bit

This bit indicates that the controller is in the System Mode. It is always set.

4 CAB – Communications Active Bit

This bit is set (1) when at least one other device is on the DH-485 network. If no other devices are on the network, this bit is cleared (0).

5 to 14 Reserved

15 Communications Toggle Push Button Communications Defaults Active. This bit is set (1) whenever Channel 0 is in the default communications mode. The bit is cleared (0) when Channel 0 is in user configured communications mode.

(Always 0 for 1764-LRP Processor Channel 1) This bit is not available with the Series A controllers.

0 to 7 Node Address - This byte value contains the node address of your controller on the network.

8 to 15 Baud Rate - This byte value contains the baud rate of the controller on the network.

Diagnostic Counter Blocks are shown for:

•

DH-485

•

DF1 Full-Duplex

•

DF1 Half-Duplex Slave

•

Modbus™ RTU Slave

•

ASCII

Table 3.12 DH-485 Diagnostic Counters Block

8

9

10

11

Word Bit

6

7

-

-

Description

Diagnostic Counters Category Identifier Code (always 2)

Length (always 30)

-

Format Code (always 0)

Total Message Packets Received

Total Message Packets Sent

0 to 7 Message Packet Retries

8 to 15 Retry Limit Exceeded (Non-Delivery)



Table 3.12 DH-485 Diagnostic Counters Block

Word Bit

12

Description

0 to 7 NAK – No Memories Sent

13

8 to 15 NAK – No Memories Received

0 to 7 Total Bad Message Packets Received

14 to 22 -

8 to 15 Reserved

Reserved

Table 3.13 DF1 Full-Duplex Diagnostic Counters Block

11

12

13

14

7

8

Word Bit

6 -

9

-

-

0

1

10

Description


Length (always 30)


2

3

CTS

RTS

Reserved

Channel 0 - Reserved, Channel 1 - DCD

-

4 to 15 Reserved


-

-

-

-


Undelivered Message Packets

ENQuiry Packets Sent

NAK Packets Received

15

16

17

18

19 to 22 -

-

-

-

-

ENQuiry Packets Received

Bad Message Packets Received and NAKed

No Buffer Space and NAK’ed

Duplicate Message Packets Received

Reserved

Table 3.14 DF1 Half-Duplex Slave Diagnostic Counters Block

10

11

12

13

8

9

Word Bit

6

7

-

-

1

2

-

0

Description


Length (always 30)


CTS

RTS

Reserved

-

-

-

-

3 Channel 0 - Reserved, Channel 1 - DCD

4 to 15 Reserved



Undelivered Message Packets

Message Packets Retried




Table 3.14 DF1 Half-Duplex Slave Diagnostic Counters Block

Word Bit

14 -

15

16

17

18

19 to 22 -

-

-

-

-

Description

NAK Packets Received

Polls Received

Bad Message Packets Received

No Buffer Space

Duplicate Message Packets Received

Reserved

Table 3.15 Modbus RTU Slave Diagnostic Counters Block

(MicroLogix 1200 Controllers, and MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors)

8

9

Word Bit

6

7

-

-

1

2

-

0

Description


Length (always 30)


CTS

RTS

Reserved

10

11

12

13

14

15 to 22 -

-

-

-

-

-

3 Channel 0 - Reserved, Channel 1 - DCD

4 to 15 Reserved


Total Message Packets Received for This Slave


Link Layer Error Count

Link Layer Error Code

Reserved

Table 3.16 ASCII Diagnostic Counters Block

(MicroLogix 1500 1764-LRP Processors only)

7

8

Word Bit

6 -

9

-

-

0

1

10

Description

DLL Diagnostic Counters Category Identifier code (always 2)

Length (always 30)


2

3

CTS

RTS

Reserved

Channel 0 - Reserved, Channel 1 - DCD

4 to 15 Reserved

0 Software Handshaking Status

11

12 -

-

1 to 15 Reserved

Echo Character Count

Received Character Count


Table 3.16 ASCII Diagnostic Counters Block

(MicroLogix 1500 1764-LRP Processors only)

Word Bit

13 to 18 -

19

20 to 22 -

-

Description

Reserved

Bad Character Count

Reserved

Table 3.17 Active Node Table Block

Word Description

23 Active Node Table Category Identifier Code (always 3)

24

25

26

27

Length (always 4 for DH-485, always 0 for DF1 Full-Duplex, DF1 Half-Duplex Slave,

Modbus RTU Slave, and ASCII)


Number of Nodes (always 32 for DH-485, always 0 for DF1 Full-Duplex, DF1

Half-Duplex Slave, Modbus RTU Slave, and ASCII)

Active Node Table – Nodes 0 to 15 (CS0:27/1 is node 1, CS0:27/2 is node 2, etc.) This is a bit-mapped register that displays the status of each node on the network. If a bit is set (1), the corresponding node is active on the network. If a bit is clear (0), the corresponding node is inactive.

28 Active Node Table – Nodes 16 to 31 (CS0:28/1 is node 16, CS0:28/2 is node 17, etc.)

This is a bit-mapped register that displays the status of each node on the network. If a bit is set (1), the corresponding node is active on the network. If a bit is clear (0), the corresponding node is inactive.

29 to 42 Reserved



Table 3.18 Modbus RTU Slave Diagnostics

(MicroLogix 1200 Controllers, and MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors)

63

64

65

66

67

60

61

62

68

69

48

49

50

51

52

53

54

55

56

57

58

59

45

46

47

Word Bit

43 -

44 -

-

-

Description


Length (always 14)


Pre-Send Time Delay

0 to 7 Node Address

-

-

8 to 15 Reserved

Inter-Character Timeout

RTS Send Delay

RTS Off Delay

0 to 7 Baud Rate

8 and 9 Parity

-

-

10 to 15 Reserved


Length (always 32)

-

-

-

-

-

-


Presentation Layer Error Code

Presentation Layer Error Count

Execution Function Error Code

Last Transmitted Exception Code

Data File Number of Error Request

-

-

-

-

-

-

-

-

-

-

Element Number of Error Request

Function Code 1 Message Counter









Input/Output Status File

The input/output status (IOS) file is a read-only file in the controller that contains information on the status of the embedded and local expansion

I/O. The data file is structured as:

Table 3.19 I/O Status File

Word Description

0 Embedded Module Error Code – Always zero

1 to 6

1 to 8

Expansion Module Error Code – The word number corresponds to the module’s slot number. Refer to the I/O module’s documentation for specific information.

(MicroLogix 1200)

Expansion Module Error Code – The word number corresponds to the module’s slot number. Refer to the I/O module’s documentation for specific information.

(MicroLogix 1500)


Chapter

4

Programming Instructions Overview

1

Instruction Set

The following table shows the MicroLogix 1200 and 1500 programming instructions listed within their functional group.

Functional Group Description

High-Speed Counter The high-speed counter instructions (along with the HSC function file) allow you to monitor and control the high-speed outputs. Generally used with DC inputs.

HSL, RAC

High-Speed Outputs The high-speed output instructions (along with the PTO and PWM function files) allow you to monitor and control the high-speed outputs. Generally used with FET outputs (BXB units).

Relay-Type (Bit)

PTO, PWM

The relay-type (bit) instructions monitor and control the status of bits.

XIC, XIO, OTE, OTL, OTU, OSR, ONS, OSF

Timer and Counter

Compare

Math

The timer and counter instructions control operations based on time or the number of events.

TON, TOF, RTO, CTU, CTD, RES

The compare instructions compare values by using a specific compare operation.

EQU, NEQ, LES, LEQ, GRT, GEQ, MEQ, LIM

The math instructions perform arithmetic operations.

ADD, SUB, MUL, DIV, NEG, CLR, SQR, SCL, SCP, SWP

Conversion

Logical

Move

File

Sequencer

Program Control

Input and Output

User Interrupt

Process Control

Page

5-1

6-1

7-1

8-1

9-1

10-1

The conversion instructions multiplex and de-multiplex data and perform conversions between binary and decimal values. DCD, ENC, TOD, FRD

The logical instructions perform bit-wise logical operations on words.

AND, OR, XOR, NOT

The move instructions modify and move words.

MOV, MVM

The file instructions perform operations on file data.

COP, FLL, BSL, BSR, FFL, FFU, LFL, LFU

11-1

12-1

13-1

14-1

Sequencer instructions are used to control automatic assembly machines that have consistent and repeatable operations. SQC, SQO, SQL

The program flow instructions change the flow of ladder program execution.

JMP, LBL, JSR, SBR, RET, SUS, TND, MCR, END

The user interrupt instructions allow you to interrupt your program based on defined events.

STS, INT, UID, UIE, UIF

The process control instruction provides closed-loop control.

15-1

16-1

The input and output instructions allow you to selectively update data without waiting for the input and output scans.

17-1

IIM, IOM, REF

18-1

19-1

ASCII

Communications

Data Logging

(MicroLogix 1500

1764-LRP only)

PID

The ASCII instructions convert and write ASCII strings. They cannot be used with MicroLogix 1500

1764-LSP Series A processors.

ABL, ACB, ACI, ACL, ACN, AEX, AHL, AIC, ARD, ARL, ASC, ASR, AWA, AWT

The communication instructions read or write data to another station.

MSG, SVC

The data logging instruction allow you to capture time-stamped and date-stamped data.

DLG

20-1

21-1

22-1


4-2 Programming Instructions Overview

Using the Instruction

Descriptions

Throughout this manual, each instruction (or group of similar instructions) has a table similar to the one shown below. This table provides information for all sub-elements (or components) of an instruction or group of instructions. This table identifies the type of compatible address that can be used for each sub-element of an instruction or group of instructions in a data file or function file. The definitions of the terms used in these tables are listed below this example table.

Table 4.1 Valid Addressing Modes and File Types - Example Table

Data Files Function Files

Address

Mode

(1)

Address

Level

Parameter

Source A

Source B

• • • • • • • • • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • • • • • • • • •

Destination • • • • • • • • • • • • • • • • •

(1) See Important note about indirect addressing.

• •

• •

• •

IMPORTANT

You cannot use indirect addressing with: S, ST, MG, PD,

RTC, HSC, PTO, PWM, STI, EII, BHI, MMI, DAT, TPI, CS,

IOS, and DLS files.

The terms used within the table are defined as follows:

•

Parameter - The parameter is the information you supply to the instruction. It can be an address, a value, or an instruction-specific parameter such as a timebase.

•

Data Files - See Data Files on page 2-5.

•

Function Files - See Function Files on page 3-1.

•

CS - See Communications Status File on page 3-13.

•

IOS - See Input/Output Status File on page 3-18.

•

DLS - See Data Log Status File on pag e22-9.

•

Address Mode - See Addressing Modes on page 4-3.

•

Addressing Level - Address levels describe the granularity at which an instruction allows an operand to be used. For example, relay type instructions (XIC, XIO, etc.) must be programmed to the bit level, timer instructions (TON, TOF, etc.) must be programmed to the element level (timers have 3 words per element) and math instructions (ADD, SUB, etc.) must be programmed to the word or long word level.


Programming Instructions Overview 4-3

Addressing Modes

The MicroLogix 1200 and MicroLogix 1500 support three types of data addressing:

•

Immediate

•

Direct

•

Indirect

The MicroLogix 1200 and 1500 do not support indexed addressing.

Indexed addressing can be duplicated with indirect addressing. See

Example - Using Indirect Addressing to Duplicate Indexed Addressing on page 4-7.

How or when each type is used depends on the instruction being programmed and the type of elements specified within the operands of the instruction. By supporting these three addressing methods, the

MicroLogix 1200 and 1500 allow incredible flexibility in how data can be monitored or manipulated. Each of the addressing modes are described below.

Immediate Addressing

Immediate addressing is primarily used to assign numeric constants within instructions. For example: You require a 10 second timer, so you program a timer with a 1 second time base and a preset value of 10. The numbers

1 and 10 in this example are both forms of immediate addressing.

Direct Addressing

When you use direct addressing, you define a specific data location within the controller. Any data location that is supported by the elements of an operand within the instruction being programmed can be used. In this example we are illustrating a limit instruction, where:

•

Low Limit = Numeric value (from -32,768 to 32,767) entered from the programming software.

•

Test Value = TPI:0.POT0 (This is the current position/value of trim pot 0.)

•

High Limit = N7:17 (This is the data resident in Integer file 7, element 17.)

The Test Value (TPI:0.POT0) and High Limit (N7:17) are direct addressing examples. The Low Limit is immediate addressing.



Indirect Addressing

Indirect addressing allows components within the address to be used as pointers to other data locations within the controller. This functionality can be especially useful for certain types of applications, recipe management, batch processing and many others. Indirect addressing can also be difficult to understand and troubleshoot. It is recommended that you only use indirect addressing when it is required by the application being developed.

The MicroLogix 1200 and 1500 support indirection (indirect addressing) for Files, Words and Bits. To define which components of an address are to be indirected, a closed bracket “[ ]” is used. The following examples illustrate how to use indirect addressing.

Indirect Addressing of a Word

0000

B3:0

0

Add

Source A N7:[N10:1]

Source B

Dest

1234

N11:33

0<

1234<

0<

•

Address: N7:[N10:1]

•

In this example, the element number to be used for source A in the

ADD instruction is defined by the number located in N10:1. If the value of location N10:1 = 15, the ADD instruction operates as

“N7:15 + Source B”.

•

In this example, the element specified by N10:1 must be between 0 and 255, because all data files have a maximum individual size of 256 elements.

NOTE

If a number larger than the number of elements in the data file is placed in N10:1 (in this example), data integrity cannot be guaranteed, because a file boundary will be crossed. This may not generate a controller fault, but the data location is invalid/ unknown.



Indirect Addressing of a File

0001

Limit Test

Low Lim

Test

High Lim

10

10<

N50:100

10<

25

25<

B3:0

0

Copy File

Source #N[N50:100]:10

Dest #N7:0

Length 15

•

Address: N[N50:100]:10

•

Description: In this example, the source of the COP instruction is indirected by N50:100. The data in N50:100 defines the data file number to be used in the instruction. In this example, the copy instruction source A is defined by N[N50:100]:10. When the instruction is scanned, the data in N50:100 is used to define the data file to be used for the COP instruction. If the value of location N50:100 = 27, this instruction copies 15 elements of data from N27:10 (N27:10 to

N27:24) to N7:0 (N7:0 to N7:14)

NOTE

If a number larger than 255 is placed in N50:100 in this example, a controller fault occurs. This is because the controller has a maximum of 255 data files. In addition, the file defined by the indirection should match the file type defined by the instruction, in this example an integer file.

NOTE

This example also illustrates how to perform a limit check on the indirect address. The limit instruction at the beginning of the rung is monitoring the indirect element. If the data at N50:100 is less than 10 or greater than 25, the copy instruction is not processed.

This procedure can be used to make sure an indirect address does not access data an unintended location.



Indirect Addressing of Bit

0002

B3:0

[B25:0]

B3:0

10

END

0003

•

Address: B3/[B25:0]

•

Description: In this example, the element to be used for the indirection is B25:0. The data in B25:0 defines the bit within file B3. If the value of location B25:0 = 1017, the XIC instruction is processed using B3/1017.

NOTE

If a number larger than 4096 (or larger than the number of elements in the data file) is placed in B25:0 in this example, data integrity cannot be guaranteed.

Exceeding the number of elements in the data file would cause the file boundary to be crossed.

These are only some of the examples that can be used; others include:

•

File and Element Indirection: N[N10:0]:[N25:0]

•

Input Slot Indirection: I1:[N7:0].0

Each group of instructions may or may not allow indirection. Please review the compatibility table for each instruction to determine which elements within an instruction support indirection.

IMPORTANT

You must exercise extreme care when using indirect addressing. Always be aware of the possibility of crossing file boundaries or pointing to data that was not intended to be used.



Example - Using Indirect Addressing to Duplicate Indexed

Addressing

In this section, an indexed addressing example is shown first. Then an equivalent indirect addressing example is shown. Indexed addressing is supported by SLC 500 and MicroLogix 1000 programmable controllers.

The MicroLogix 1200 and 1500 do not support indexed addressing. This example is shown for comparison purposes.

Indexed Addressing Example

The following ADD instruction uses an indexed address in the Source A and Destination addresses. If the indexed offset value is 20 (stored in

S:24), the controller uses the data stored at the base address plus the indexed offset to perform the operation.

Indexed

Addresses

Add

Source A

Source B

Dest

#N7:0

25

#N15:0

Working

Addresses

Add

Source A

Source B

Dest

N7:20

25

N15:20

In this example, the controller uses the following addresses:

Operand

Source A

Destination

Base Address

N7:0

N15:0

Offset Value in S:24 Working Address

20

20

N7:20

N15:20

NOTE

In the SLC and ML1000 controllers, there are some instructions that clear S:24 after the instruction completes.

For this reason, you must insure that the index register is loaded with the intended value prior to the execution of an indexed instruction.



Indirect Addressing Example

An equivalent example using indirect addressing is shown below. In place of using the index register, S:24, the user can designate any other valid word address as the indirect address. Multiple indirect addresses can be used within an instruction.

The following ADD instruction uses an indirect address in the Source A and Destination addresses. If the indirect offset value is 20 (stored in

N7:3), the controller uses the data stored at the base address plus the indirect offset to perform to instruction.

Indirect

Addresses

Add

Source A N7:[N7:3]

Source B 25

Dest N15:[N7:3]

Working

Addresses

Add

Source A

Source B

Dest

N7:20

25

N15:20

In this example, the controller uses the following addresses:

Operand

Source A

Destination

Base Address

N7:0

N7:0

Offset Value in N7:3

20

20

Working Address

N7:20

N15:20


1

Chapter

5

Using the High-Speed Counter

The MicroLogix 1200 has one 20 kHz high-speed counter; the MicroLogix

1500 has two. Functionally, the counters are identical. Each counter has four dedicated inputs that are isolated from other inputs on the controller.

HSC0 utilizes inputs 0 through 3 and HSC1 (MicroLogix 1500 only) utilizes inputs 4 through 7. Each counter operates independently from the other.

NOTE

HSC0 is used in this document to define how any HSC works. The MicroLogix 1500’s HSC1 is identical in functionality.

IMPORTANT

The HSC function can only be used with the controller’s embedded I/O. It cannot be used with expansion I/O modules.

This chapter describes how to use the HSC function and also contains sections on the HSL and RAC instructions, as follows:

•

High-Speed Counter (HSC) Function File on page 5-2.

•

HSL - High-Speed Counter Load on page 5-26.

•

RAC - Reset Accumulated Value on page 5-27.


5-2 Using the High-Speed Counter

High-Speed Counter

(HSC) Function File

Within the RSLogix 500 Function File Folder, you see a HSC Function File.

This file provides access to HSC configuration data, and also allows the control program access to all information pertaining to each of the

High-Speed Counters.

NOTE

If the controller is in the run mode, the data within sub-element fields may be changing.


The HSC function, along with the PTO and PWM instructions, are different than most other controller instructions. Their operation is performed by custom circuitry that runs in parallel with the main system processor. This is necessary because of the high performance requirements of these functions.

Using the High-Speed Counter 5-3

The HSC is extremely versatile; the user can select or configure each HSC for any one of eight (8) modes of operation. (Operating Modes are

discussed later in this chapter. See section HSC Mode (MOD) on page

5-16). Some of the enhanced capabilities of the High-Speed Counters are:

•

20 kHz operation

•

High-speed direct control of outputs

•

32-bit signed integer data (count range of ± 2,147,483,647)

•

Programmable High and Low presets, and Overflow and Underflow setpoints

•

Automatic Interrupt processing based on accumulated count

•

Run-time editable parameters (from the user control program)

The High-Speed Counter function operates as described in the following diagram.

Overflow

+2,147,483,647 maximum

High Preset

0

Low Preset

Underflow

-2,147,483,648 minimum



High-Speed Counter

Function File

Sub-Elements Summary

Each HSC is comprised of 36 sub-elements. These sub-elements are either bit, word, or long word structures that are used to provide control over the HSC function, or provide HSC status information for use within the control program. Each of the sub-elements and their respective functions are described in this chapter. A summary of the sub-elements is provided in the following table. All examples illustrate HSC0. Terms and behavior for HSC1 are identical.

Table 5.1 High-Speed Counter Function File (HSC:0 or HSC:1)

Sub-Element Description Address Data Format

PFN - Program File Number

ER - Error Code

HSC:0.PFN

HSC:0.ER

UIX - User Interrupt Executing HSC:0/UIX

UIE - User Interrupt Enable

UIL - User Interrupt Lost

UIP - User Interrupt Pending

HSC:0/UIE

HSC:0/UIL

HSC:0/UIP

FE - Function Enabled

AS - Auto Start

ED - Error Detected

CE - Counting Enabled

SP - Set Parameters

LPM - Low Preset Mask

HSC:0/FE

HSC:0/AS

HSC:0/ED

HSC:0/CE

HSC:0/SP

HSC:0/LPM

HPM - High Preset Mask

UFM - Underflow Mask

OFM - Overflow Mask

LPI - Low Preset Interrupt

HPI - High Preset Interrupt

UFI - Underflow Interrupt

OFI - Overflow Interrupt

LPR - Low Preset Reached

HPR - High Preset Reached

DIR - Count Direction

UF - Underflow

OF - Overflow

HSC:0/HPM

HSC:0/UFM

HSC:0/OFM

HSC:0/LPI

HSC:0/HPI

HSC:0/UFI

HSC:0/OFI

HSC:0/LPR

HSC:0/HPR

HSC:0/DIR

HSC:0/UF

HSC:0/OF

MD - Mode Done

CD - Count Down

CU - Count Up

MOD - HSC Mode

ACC - Accumulator

HIP - High Preset

LOP - Low Preset

OVF - Overflow

UNF - Underflow

OMB - Output Mask Bits

HPO - High Preset Output

LPO - Low Preset Output

HSC:0/MD

HSC:0/CD

HSC:0/CU

HSC:0.MOD

HSC:0.ACC

HSC:0.HIP

HSC:0.LOP

HSC:0.OVF

HSC:0.UNF

HSC:0.OMB

HSC:0.HPO

HSC:0.LPO

(1) For Mode descriptions, see HSC Mode (MOD) on page 5-16.

n/a = not applicable bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit bit word (INT) word (INT) bit bit bit bit word (INT) long word (32-bit INT) long word (32-bit INT) long word (32-bit INT) long word (32-bit INT) long word (32-bit INT) word (16-bit binary) word (16-bit binary) word (16-bit binary)

Function User Program

Access

control read only status read only status read only control read/write status read/write status read only control read/write control read only status read only control read/write control read/write control read/write control read/write control read/write control read/write status read/write status read/write status read/write status read/write status read only status read only status read only status read/write status read/write status read/write status read only status read only control read only control read/write control read/write control read/write control read/write control read/write control read only control read/write control read/write

0 to 7

2 to 7

2 to 7

0 to 7

0 to 7

0 to 7

0 to 7

2 to 7

0 to 7

2 to 7

0 to 7

2 to 7

0 to 7

0 to 7

0 to 7

0 to 7

0 to 7

2 to 7

HSC

Modes

(1)

0 to 7

0 to 7

0 to 7

0 to 7

0 to 7

0 to 7

2 to 7

0 to 7

2 to 7

0 to 7

0 to 7

2 to 7

0 or 1

2 to 7

0 to 7

0 to 7

0 to 7

0 to 7

For More

Information

5-14

5-10

5-12

5-15

5-12

5-13

5-11

5-12

5-14

5-10

5-11

5-13

5-6

5-6

5-6

5-7

5-7

5-9

5-5

5-5

5-8

5-8

5-9

5-9

5-22

5-23

5-23

5-24

5-25

5-25

5-15

5-15

5-16

5-16

5-22

5-22


HSC Function File

Sub-Elements


All examples illustrate HSC0. Terms and behavior for HSC1 are identical.

Program File Number (PFN)

Description Address Data Format HSC Modes

(1)

PFN - Program

File Number

HSC:0.PFN word (INT) 0 to 7


Type User Program Access

control read only

The PFN (Program File Number) variable defines which subroutine is called (executed) when HSC0 counts to High Preset or Low Preset, or through Overflow or Underflow. The integer value of this variable defines which program file will run at that time. A valid subroutine file is any program file (3 to 255).

See also:Interrupt Latency on page 18-5.

Error Code (ER)

Description Address Data Format

ER - Error Code HSC:0.ER word (INT)

HSC Modes

(1)

0 to 7



status read only

The ERs (Error Codes) detected by the HSC sub-system are displayed in this word. Errors include:

Table 5.2 HSC Error Codes

Error Code

1

2

Name

Invalid File

Number

Invalid Mode

Mode

(1)

n/a n/a

Description

Interrupt (program) file identified in HSC:0.PFN is less than 3, greater than 255, or does not exist

Invalid Mode

(1)

High preset is less than or equal to zero (0) 3

4

Invalid High

Preset

0,1

2 to 7

Invalid Overflow 0 to 7

High preset is less than or equal to low preset

High preset is greater than overflow




Function Enabled (FE)


FE - Function

Enabled

HSC:0/FE bit

HSC Modes

(1)

0 to 7



control read/write

The FE (Function Enabled) is a status/control bit that defines when the

HSC interrupt is enabled, and that interrupts generated by the HSC are processed based on their priority.

This bit can be controlled by the user program or is automatically set by the HSC sub-system if auto start is enabled.

See also:Priority of User Interrupts on page 18-4.

Auto Start (AS)


AS - Auto Start HSC:0/AS bit

HSC Modes

(1) Type User Program Access

0 to 7


control read only

The AS (Auto Start) is configured with the programming device and stored as part of the user program. The auto start bit defines if the HSC function automatically starts whenever the controller enters any run or test mode.

The CE (Counting Enabled) bit must also be set to enable the HSC.

Error Detected (ED)

Description

ED - Error

Detected

Address Data Format

HSC:0/ED bit

HSC Modes

(1)

0 to 7



status read only

The ED (Error Detected) flag is a status bit that can be used in the control program to detect if an error is present in the HSC sub-system. The most common type of error that this bit represents is a configuration error.

When this bit is set (1), you should look at the specific error code in parameter HSC:0.ER.

This bit is maintained by the controller and is set and cleared automatically.



Counting Enabled (CE)


CE - Counting

Enabled

HSC:0/CE bit

HSC Modes

(1)

0 to 7



control read/write

The CE (Counting Enabled) control bit is used to enable or disable the

High-Speed Counter. When set (1), counting is enabled, when clear (0, default) counting is disabled. If this bit is disabled while the counter is running, the accumulated value is held; if the bit is then set, counting resumes.

This bit can be controlled by the user program and retains its value through a power cycle. This bit must be set for the high-speed counter to operate.

Set Parameters (SP)

Description

SP - Set

Parameters


HSC:0/SP bit

HSC Modes

(1)

0 to 7



control read/write

The SP (Set Parameters) control bit is used to load new variables to the

HSC sub-system. When an OTE instruction with the address of HSC:0/SP is solved true (off-to-on rung transition), all configuration variables currently stored in the HSC function are checked and loaded into the HSC sub-system. The HSC sub-system then operates based on those newly loaded settings.

This bit is controlled by the user program and retains its value through a power cycle. It is up to the user program to set and clear this bit. SP can be toggled while the HSC is running and no counts are lost.



User Interrupt Enable (UIE)

Description Address Data

Format

UIE - User Interrupt Enable HSC:0/UIE bit


HSC

Modes

(1)

0 to 7

Type User Program

Access

control read/write

The UIE (User Interrupt Enable) bit is used to enable or disable HSC subroutine processing. This bit must be set (1) if the user wants the controller to process the HSC subroutine when any of the following conditions exist:

•

Low preset reached

•

High preset reached

•

Overflow condition - count up through the overflow value

•

Underflow condition - count down through the underflow value

If this bit is cleared (0), the HSC sub-system does not automatically scan the HSC subroutine. This bit can be controlled from the user program

(using the OTE, UIE, or UID instructions).

ATTENTION

!

If you enable interrupts during the program scan via an

OTL, OTE, or UIE, this instruction must be the last instruction executed on the rung (last instruction on last branch). It is recommended this be the only output instruction on the rung.

User Interrupt Executing (UIX)

Description Address Data

Format

UIX - User Interrupt Executing HSC:0/UIX bit


HSC Modes

(1)

0 to 7


Access

status read only

The UIX (User Interrupt Executing) bit is set (1) whenever the HSC sub-system begins processing the HSC subroutine due to any of the following conditions:

•

Low preset reached

•

High preset reached

•

Overflow condition - count up through the overflow value

•

Underflow condition - count down through the underflow value

The HSC UIX bit can be used in the control program as conditional logic to detect if an HSC interrupt is executing.

The HSC sub-system will clear (0) the UIX bit when the controller completes its processing of the HSC subroutine.



User Interrupt Pending (UIP)

Description Address

UIP - User

Interrupt

Pending

Data Format

HSC:0/UIP bit

HSC Modes

(1)

0 to 7



status read only

The UIP (User Interrupt Pending) is a status flag that represents an interrupt is pending. This status bit can be monitored or used for logic purposes in the control program if you need to determine when a subroutine cannot be executed immediately.

This bit is maintained by the controller and is set and cleared automatically.

User Interrupt Lost (UIL)

Description Address Data Format HSC Modes (1)

UIL - User

Interrupt Lost

HSC:0/UIL bit 0 to 7



status read/write

The UIL (User Interrupt Lost) is a status flag that represents an interrupt has been lost. The controller can process 1 active and maintain up to 2 pending user interrupt conditions.

This bit is set by the controller. It is up to the control program to utilize, track if necessary, and clear the lost condition.

Low Preset Mask (LPM)


LPM - Low

Preset Mask

Data Format

HSC:0/LPM bit

HSC Modes

(1) Type User Program Access

2 to 7


control read/write

The LPM (Low Preset Mask) control bit is used to enable (allow) or disable (not allow) a low preset interrupt from occurring. If this bit is clear

(0), and a Low Preset Reached condition is detected by the HSC, the HSC user interrupt is not executed.

This bit is controlled by the user program and retains its value through a power cycle. It is up to the user program to set and clear this bit.



Low Preset Interrupt (LPI)


LPI - Low

Preset Interrupt

HSC:0/LPI bit

HSC Modes

(1)

2 to 7



status read/write

The LPI (Low Preset Interrupt) status bit is set (1) when the HSC accumulator reaches the low preset value and the HSC interrupt has been triggered. This bit can be used in the control program to identify that the low preset condition caused the HSC interrupt. If the control program needs to perform any specific control action based on the low preset, this bit would be used as conditional logic.

This bit can be cleared (0) by the control program and is also be cleared by the HSC sub-system whenever these conditions are detected:

•

High Preset Interrupt executes

•

Underflow Interrupt executes

•

Overflow Interrupt executes

•

Controller enters an executing mode

Low Preset Reached (LPR)


(1)

LPR - Low

Preset

Reached

HSC:0/LPR bit 2 to 7



status read only

The LPR (Low Preset Reached) status flag is set (1) by the HSC sub-system whenever the accumulated value (HSC:0.ACC) is less than or equal to the low preset variable (HSC:0.LOP).

This bit is updated continuously by the HSC sub-system whenever the controller is in an executing mode.



High Preset Mask (HPM)


(1)

HPM - High

Preset Mask

HSC:0/HPM bit 0 to 7



control read/write

The HPM (High Preset Mask) control bit is used to enable (allow) or disable (not allow) a high preset interrupt from occurring. If this bit is clear (0), and a High Preset Reached condition is detected by the HSC, the

HSC user interrupt is not executed.


High Preset Interrupt (HPI)

Description

HPI - High

Preset Interrupt


HSC:0/HPI bit

HSC Modes

(1)

0 to 7



status read/write

The HPI (High Preset Interrupt) status bit is set (1) when the HSC accumulator reaches the high preset value and the HSC interrupt is triggered. This bit can be used in the control program to identify that the high preset condition caused the HSC interrupt. If the control program needs to perform any specific control action based on the high preset, this bit is used as conditional logic.

This bit can be cleared (0) by the control program and is also cleared by the HSC sub-system whenever these conditions are detected:

•

Low Preset Interrupt executes

•


•


•




High Preset Reached (HPR)


(1)

HPR - High

Preset Reached

HSC:0/HPR bit 2 to 7



status read only

The HPR (High Preset Reached) status flag is set (1) by the HSC sub-system whenever the accumulated value (HSC:0.ACC) is greater than or equal to the high preset variable (HSC:0.HIP).

This bit is updated continuously by the HSC sub-system whenever the controller is in an executing mode.

Underflow (UF)


UF - Underflow HSC:0/UF bit 0 to 7



status read/write

The UF (Underflow) status flag is set (1) by the HSC sub-system whenever the accumulated value (HSC:0.ACC) has counted through the underflow variable (HSC:0.UNF).

This bit is transitional and is set by the HSC sub-system. It is up to the control program to utilize, track if necessary, and clear (0) the underflow condition.

Underflow conditions do not generate a controller fault.

Underflow Mask (UFM)


UFM -

Underflow

Mask

Data Format

HSC:0/UFM bit

HSC Modes

(1)

2 to 7



control read/write

The UFM (Underflow Mask) control bit is used to enable (allow) or disable (not allow) a underflow interrupt from occurring. If this bit is clear

(0), and a Underflow Reached condition is detected by the HSC, the HSC user interrupt is not executed.




Underflow Interrupt (UFI)


(1)

UFI - Underflow

Interrupt

HSC:0/UFI bit 2 to 7



status read/write

The UFI (Underflow Interrupt) status bit is set (1) when the HSC accumulator counts through the underflow value and the HSC interrupt is triggered. This bit can be used in the control program to identify that the underflow condition caused the HSC interrupt. If the control program needs to perform any specific control action based on the underflow, this bit is used as conditional logic.


•


•


•


•


Overflow (OF)


OF - Overflow HSC:0/OF bit

HSC Modes

(1)

0 to 7



status read/write

The OF (Overflow) status flag is set (1) by the HSC sub-system whenever the accumulated value (HSC:0.ACC) has counted through the overflow variable (HSC:0.OF).

This bit is transitional and is set by the HSC sub-system. It is up to the control program to utilize, track if necessary, and clear (0) the overflow condition.

Overflow conditions do not generate a controller fault.



Overflow Mask (OFM)


(1)


OFM - Overflow

Mask

HSC:0/OFM bit 0 to 7 control read/write


The OFM (Overflow Mask) control bit is used to enable (allow) or disable

(not allow) an overflow interrupt from occurring. If this bit is clear (0), and an overflow reached condition is detected by the HSC, the HSC user interrupt is not executed.


Overflow Interrupt (OFI)


OFI - Overflow

Interrupt

HSC:0/OFI bit

HSC Modes

(1)

0 to 7



status read/write

The OFI (Overflow Interrupt) status bit is set (1) when the HSC accumulator counts through the overflow value and the HSC interrupt is triggered. This bit can be used in the control program to identify that the overflow variable caused the HSC interrupt. If the control program needs to perform any specific control action based on the overflow, this bit is used as conditional logic.


•


•


•


•




Count Direction (DIR)


DIR - Count

Direction

Data Format

HSC:0/DIR bit

HSC Modes

(1)

0 to 7



status read only

The DIR (Count Direction) status flag is controlled by the HSC sub-system.

When the HSC accumulator counts up, the direction flag is set (1).

Whenever the HSC accumulator counts down, the direction flag is cleared

(0).

If the accumulated value stops, the direction bit retains its value. The only time the direction flag changes is when the accumulated count reverses.

This bit is updated continuously by the HSC sub-system whenever the controller is in a run mode.

Mode Done (MD)


MD - Mode

Done

Data Format

HSC:0/MD bit

HSC Modes

(1)

0 or 1



status read/write

The MD (Mode Done) status flag is set (1) by the HSC sub-system when the HSC is configured for Mode 0 or Mode 1 behavior, and the accumulator counts up to the High Preset.

Count Down (CD)


CD - Count Down HSC:0/CD bit 2 to 7



status read only

The CD (Count Down) bit is used with the bidirectional counters (modes

2 to 7). If the CE bit is set, the CD bit is set (1). If the CE bit is clear, the

CD bit is cleared (0).



Count Up (CU)


CU - Count Up HSC:0/CU bit

HSC Modes

(1)

0 to 7



status read only

The CU (Count Up) bit is used with all of the HSCs (modes 0 to 7). If the

CE bit is set, the CU bit is set (1). If the CE bit is clear, the CU bit is cleared

(0).

HSC Mode (MOD)


MOD - HSC Mode HSC:0.MOD word (INT)


control read only

The MOD (Mode) variable sets the High-Speed Counter to one of 8 types of operation. This integer value is configured through the programming device and is accessible in the control program as a read-only variable.

5

6

7

2

3

4

Table 5.3 HSC Operating Modes

Mode

Number

0

Type

1

Up Counter - The accumulator is immediately cleared (0) when it reaches the high preset. A low preset cannot be defined in this mode.

Up Counter with external reset and hold - The accumulator is immediately cleared

(0) when it reaches the high preset. A low preset cannot be defined in this mode.

Counter with external direction

Counter with external direction, reset, and hold

Two input counter (up and down)

Two input counter (up and down) with external reset and hold

Quadrature counter (phased inputs A and B)

Quadrature counter (phased inputs A and B) with external reset and hold



HSC Mode 0 - Up Counter

Table 5.4 HSC Mode 0 Examples

(1)

Input Terminals

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

Example 2

Count

⇑

⇑ on

(1)

⇓ off (0)

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Not Used

(1) HSC1 only applies to the MicroLogix 1500.

Blank cells = don’t care,

⇑

= rising edge,

⇓

= falling edge

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Not Used

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Not Used

CE Bit Comments

on (1) HSC Accumulator + 1 count off (0) Hold accumulator value

NOTE

Inputs I1:0.0/0 through I1:0.0/7 are available for use as inputs to other functions regardless of the HSC being used.

HSC Mode 1 - Up Counter with External Reset and Hold


(1)

Input Terminals

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

Count

⇑

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Not Used

Example 2

Example3

Example 4

on

(1)

⇓ off

(0)

Example 5



⇑

= rising edge,

⇓

= falling edge

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Reset

on

(1)

⇓ off

(0)

⇓ on

(1) on

(1) on

(1)

⇓

⇓ off

(0) off

(0) off

(0)

⇑

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Hold

on

(1)

CE Bit

off (0)

Comments

off

(0) on (1) HSC Accumulator + 1 count

Hold accumulator value



Clear accumulator (=0)

NOTE




HSC Mode 2 - Counter with External Direction


(1)

Input Terminals

I1:0.0/0 (HSC0)

Function

Example 1

Example 2

I1:0.0/4 (HSC1)

Count

⇑

⇑

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Direction

off

(0)

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Not Used

on

(1)

Example3



⇑

= rising edge,

⇓

= falling edge

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Not Used

CE Bit Comments

on (1) HSC Accumulator + 1 count on (1) off (0)

HSC Accumulator - 1 count


NOTE


HSC Mode 3 - Counter with External Direction, Reset, and Hold


(1)

Input Terminals

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

Count

⇑

Example 2

Example3

Example 4

Example 5

Example 6

⇑ on

(1)

⇓ off

(0)

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Direction

on

(1) off

(0)

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Reset

on

(1)

⇓ off

(0) on

(1)

⇓ off

(0) on

(1)

⇓ off

(0)

⇓ on

(1) on

(1)

⇓ off

(0) off

(0)

⇑

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Hold

on

(1)

CE Bit

off (0)

Comments

off

(0) on (1) HSC Accumulator + 1 count off

(0) on (1) HSC Accumulator - 1 count







⇑

= rising edge,

⇓

= falling edge

NOTE




HSC Mode 4 - Two Input Counter (up and down)


(1)

Input Terminals

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

Count Up

⇑

Example 2

on

(1)

⇓

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1) off

(0)

Count Down Not Used

on

(1)

⇓ off

(0)

⇑

Example3



⇑

= rising edge,

⇓

= falling edge

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Not Used

CE Bit Comments

on (1) HSC Accumulator + 1 count on (1) off (0)

HSC Accumulator - 1 count


NOTE


HSC Mode 5 - Two Input Counter (up and down) with External Reset and Hold


(1)

Input Terminals

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

Count

⇑

Example 2

on

(1)

⇓

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1) off

(0)

Direction

on

(1)

⇓

⇑ off

(0)

Example3

Example 4

Example 5

Example 6

on

(1)

⇓ off

(0)

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Reset

on

(1)

⇓ off

(0) on

(1)

⇓ off

(0) on

(1)

⇓ off

(0)

⇓ on

(1) on

(1)

⇓ off

(0) off

(0)

⇑

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Hold

on

(1)

CE Bit

off (0)

Comments

off

(0) on (1) HSC Accumulator + 1 count off

(0) on (1) HSC Accumulator - 1 count







⇑

= rising edge,

⇓

= falling edge

NOTE




Using the Quadrature Encoder

The Quadrature Encoder is used for determining direction of rotation and position for rotating, such as a lathe. The Bidirectional Counter counts the rotation of the Quadrature Encoder.

The figure below shows a quadrature encoder connected to inputs 0, 1, and 2. The count direction is determined by the phase angle between A and B. If A leads B, the counter increments. If B leads A, the counter decrements.

The counter can be reset using the Z input. The Z outputs from the encoders typically provide one pulse per revolution.

Quadrature Encoder

Forward Rotation

A

B

Z

(Reset input)

Input 0

Input 1

Input 2

Reverse Rotation

A

B

1

2

3

2

1

Count

HSC Mode 6 - Quadrature Counter (phased inputs A and B)


(1)

Input Terminals I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Function

Example 1

(2)

Count A

⇑

Example 2

Example3

(3)

⇓ off (0) on (1)

Example 4

Example 5

Example 6

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Count B

on (1) off (0) off (0)


I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Not Used

(2) Count input A leads count input B.

(3) Count input B leads count input A.


⇑

= rising edge,

⇓

= falling edge

NOTE

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Not Used

CE Bit Comments

on (1) HSC Accumulator + 1 count on (1) HSC Accumulator - 1 count



Hold accumulator value off (0) Hold accumulator value




HSC Mode 7 - Quadrature Counter (phased inputs A and B) With External Reset and Hold


(1)

Input

Terminals

Function

Example 1

(2)

Example 2

(3)

Example3

Example 4

Example 5

Example 6

Example 7

I1:0.0/0 (HSC0)

I1:0.0/4 (HSC1)

Count A

⇑ on (1)

⇓

⇓ off (0)


(2) Count input A leads count input B.

(3) Count input B leads count input A.

I1:0.0/1 (HSC0)

I1:0.0/5 (HSC1)

Count B

off (0)

I1:0.0/2 (HSC0)

I1:0.0/6 (HSC1)

Z reset

on (1) off (0) off (0) on (1) off (0)

I1:0.0/3 (HSC0)

I1:0.0/7 (HSC1)

Hold

CE

Bit

Comments

off (0) on (1) HSC Accumulator + 1 count off (0) on (1) off (0) off (0) on (1) HSC Accumulator - 1 count

Reset accumulator to zero



Hold accumulator value off (0) Hold accumulator value


⇑

= rising edge,

⇓

= falling edge

NOTE




Accumulator (ACC)

Description Address Data Format Type User Program Access

ACC - Accumulator HSC:0.ACC long word (32-bit INT) control read/write

The ACC (Accumulator) contains the number of counts detected by the

HSC sub-system. If either mode 0 or mode 1 is configured, the value of the

software accumulator is cleared (0) when a high preset is reached or when an overflow condition is detected.

High Preset (HIP)


HIP - High Preset HSC:0.HIP long word (32-bit INT) control read/write

The HIP (High Preset) is the upper setpoint (in counts) that defines when the HSC sub-system generates an interrupt. To load data into the high preset, the control program must do one of the following:

•

Toggle (low to high) the Set Parameters (HSC:0/SP) control bit. When the SP bit is toggled high, the data currently stored in the HSC function file is transferred/loaded into the HSC sub-system.

•

Load new HSC parameters using the HSL instruction. See HSL -

High-Speed Counter Load on page 5-26.

The data loaded into the high preset must be less than or equal to the data resident in the overflow (HSC:0.OVF) parameter or an HSC error is generated.

Low Preset (LOP)

Description

LOP - Low Preset

Address Data Format Type User Program Access

HSC:0.LOP

long word (32-bit INT) control read/write

The LOP (Low Preset) is the lower setpoint (in counts) that defines when the HSC sub-system generates an interrupt. To load data into the low preset, the control program must do one of the following:

•

Toggle (low to high) the Set Parameters (HSC:0/SP) control bit. When the SP bit is toggled high, the data currently stored in the HSC function file is transferred/loaded into the HSC sub-system.

•

Load new HSC parameters using the HSL instruction. See HSL -

High-Speed Counter Load on page 5-26.

The data loaded into the low preset must greater than or equal to the data resident in the underflow (HSC:0.UNF) parameter, or an HSC error is generated. (If the underflow and low preset values are negative numbers, the low preset must be a number with a smaller absolute value.)



Overflow (OVF)

Description

OVF - Overflow

Address Data Format Type User Program Access

HSC:0.OVF


The OVF (Overflow) defines the upper count limit for the counter. If the counter’s accumulated value increments past the value specified in this variable, an overflow interrupt is generated. When the overflow interrupt is generated, the HSC sub-system rolls the accumulator over to the underflow value and the counter continues counting from the underflow value (counts are not lost in this transition). The user can specify any value for the overflow position, provided it is greater than the underflow value and falls between -2,147,483,648 and 2,147,483,647.

To load data into the overflow variable, the control program must toggle

(low to high) the Set Parameters (HSC:0.0/SP) control bit. When the SP bit is toggled high, the data currently stored in the HSC function file is transferred/loaded into the HSC sub-system.

NOTE

Data loaded into the overflow variable must be greater than the data resident in the high preset

(HSC:0.HIP) or an HSC error is generated.

Underflow (UNF)


UNF - Underflow HSC:0.UNF


The UNF (Underflow) defines the lower count limit for the counter. If the counter’s accumulated value decrements past the value specified in this variable, an underflow interrupt is generated. When the underflow interrupt is generated, the HSC sub-system resets the accumulated value to the overflow value and the counter then begins counting from the overflow value (counts are not lost in this transition). The user can specify any value for the underflow position, provided it is less than the overflow value and falls between -2,147,483,648 and 2,147,483,647.

To load data into the underflow variable, the control program must toggle

(low to high) the Set Parameters (HSC:0.0/SP) control bit. When the SP bit is toggled high, the data currently stored in the HSC function file is transferred/loaded into the HSC sub-system.

NOTE

Data loaded into the overflow variable must be greater than the data resident in the high preset (HSC:0.HIP) or an HSC error is generated.



Output Mask Bits (OMB)


OMB - Output Mask Bits HSC:0.OMB

word (16-bit binary) control read only

The OMB (Output Mask Bits) define which outputs on the controller can be directly controlled by the high-speed counter. The HSC sub-system has the ability to directly (without control program interaction) turn outputs

ON or OFF based on the HSC accumulator reaching the High or Low presets. The bit pattern stored in the OMB variable defines which outputs are controlled by the HSC and which outputs are not controlled by the

HSC.

The bit pattern of the OMB variable directly corresponds to the output bits on the controller. Bits that are set (1) are enabled and can be turned on or off by the HSC sub-system. Bits that are clear (0) cannot be turned on or off by the HSC sub-system. The mask bit pattern can be configured only during initial setup.

The table below illustrates this relationship:

Table 5.12 Affect of HSC Output Mask on Base Unit Outputs

Output Address

HSC:0.HPO (high preset output)

16-Bit Signed Integer Data Word

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 1 1 0 1 0 0 1 1 0 0 1

HSC:0.OMB (output mask) 1 0 0 0 0 1 1 1 0 0 1 1

O0:0.0

0 0 0 1 0 1

The outputs shown in the black boxes are the outputs under the control of the HSC sub-system. The mask defines which outputs can be controlled. The high preset output or low preset output values (HPO or

LPO) define if each output is either ON (1) or OFF (0). Another way to view this is that the high or low preset output is written through the output mask, with the output mask acting like a filter.

The bits in the gray boxes are unused. The first 12 bits of the mask word are used and the remaining mask bits are not functional because they do not correlate to any physical outputs on the base unit.

The mask bit pattern can be configured only during initial setup.



High Preset Output (HPO)


HPO - High Preset Output HSC:0.HPO

word (16-bit binary) control read/write

The HPO (High Preset Output) defines the state (1 = ON or 0 = OFF) of

the outputs on the controller when the high preset is reached. See Output

Mask Bits (OMB) on page 5-24 for more information on how to directly

turn outputs on or off based on the high preset being reached.

The high output bit pattern can be configured during initial setup, or while the controller is operating. Use the HSL instruction or the SP bit to load the new parameters while the controller is operating.

Low Preset Output (LPO)


LPO - Low Preset Output HSC:0.LPO

word (16-bit binary) control read/write

The LPO (Low Preset Output) defines the state (1 = “on”, 0 = “off”) of the

outputs on the controller when the low preset is reached. See Output

Mask Bits (OMB) on page 5-24 for more information on how to directly

turn outputs on or off based on the low preset being reached.

The low output bit pattern can be configured during initial setup, or while the controller is operating. Use the HSL instruction or the SP bit to load the new parameters while the controller is operating.



HSL - High-Speed

Counter Load

High Speed Counter Load

HSC Number HSC0

High Preset

Low Preset

N7:0

N7:1

Output High Source

Output Low Source

N7:2

N7:3

Instruction Type: output

Controller Data Size

MicroLogix 1200 word long word


Execution Time When Rung Is:

True

46.7

µ s

47.3

µ s

39.7

µ s

40.3

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The HSL (High-Speed Load) instruction allows the high and low presets, and high and low output source to be applied to a high-speed counter.

These parameters are described below:

•

Counter Number - Specifies which high-speed counter is being used;

0 = HSC0 and 1 = HSC1 (MicroLogix 1500 only).

•

High Preset - Specifies the value in the high preset register. The data ranges for the high preset are -32786 to 32767 (word) and

-2,147,483,648 to 2,147,483,647 (long word).

•

Low Preset - Specifies the value in the low preset register. The data ranges for the low preset are -32786 to 32767 (word) and

-2,147,483,648 to 2,147,483,647 (long word).

•

Output High Source - Specifies the value in the output high register.

The data range for the output high source is from 0 to 65,535.

•

Output Low Source - Specifies the value in the output low register.

The data range for the output low source is from 0 to 65,535.

Valid Addressing Modes and File Types are shown below:

Table 5.13 HSL Instruction Valid Addressing Modes and File Types

For definitions of the terms used in this table see Using the Instruction Descriptions on page 4-2.


Address

Mode

Parameter

Address

Level

Counter Number

High Preset

Low Preset

• •

• •

Output High Source • •

Output Low Source • •

• • • •

• • • •

• • • •

• • • •

•

• • •

• • •

• • •

• • •

• •

• •

• •

• •



RAC - Reset

Accumulated Value

Reset Accumulated Value

Counter HSC0

Source 0


Controller Execution Time When Rung Is:

True

MicroLogix 1200 21.2

µ s


µ s

False

0.0

0.0

µ

µ s s

The RAC instruction resets the high-speed counter and allows a specific value to be written to the HSC accumulator. The RAC instruction uses the following parameters:

•

Counter Number - Specifies which high-speed counter is being used:

– Counter Number 0 = HSC0 (MicroLogix 1200 and 1500)

– Counter Number 1 = HSC1 (MicroLogix 1500 only)

•

Source - Specifies the location of the data to be loaded into the HSC accumulator. The data range is from -2,147,483,648 to 2,147,483,647.

Valid Addressing Modes and File Types are shown below:

Table 5.14 RAC Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Counter Number

Source •

•

• • • •




1

Chapter

6

Using High-Speed Outputs

The high-speed output instructions allow you to control and monitor the

PTO and PWM functions which control the physical high-speed outputs.

Instruction

PTO - Pulse Train Output

PWM - Pulse Width Modulation

Used To:

Generate stepper pulses

Generate PWM output

Page

6-2

6-18

PTO - Pulse Train Output

Pulse Train Output

PTO Number 0

IMPORTANT

The PTO function can only be used with the controller’s embedded I/O. It cannot be used with expansion I/O modules.

IMPORTANT

The PTO instruction should only be used with MicroLogix

1200 and 1500 BXB units. Relay outputs are not capable of performing very high-speed operations.


Table 6.1 Execution Time for the PTO Instruction

Controller When Rung Is:

True


µ s


µ s

False

24.4

µ s

21.1

µ s


6-2 Using High-Speed Outputs

Pulse Train Output

Function

The MicroLogix 1200 1762-L24BXB and 1762-L40BXB controllers each support one high-speed output. A MicroLogix 1500 controller utilizing a

1764-28BXB Base Unit supports two high-speed outputs. These outputs can be used as standard outputs (not high-speed) or individually configured for PTO or PWM operation. The PTO functionality allows a simple motion profile or pulse profile to be generated directly from the controller. The pulse profile has three primary components:

•

Total number of pulses to be generated

•

Accelerate/decelerate intervals

•

Run interval

The PTO instruction, along with the HSC and PWM functions, are different than most other controller instructions. Their operation is performed by custom circuitry that runs in parallel with the main system processor. This is necessary because of the high performance requirements of these functions.

In this implementation, the user defines the total number of pulses to be generated (which corresponds to distance traveled), and how many pulses to use for each acceleration/deceleration period. The number of pulses not used in the acceleration/deceleration period defines how many pulses are generated during the run phase. In this implementation, the acceleration/deceleration intervals are the same.

Within the PTO function file, there are PTO element(s). An element can be set to control either output 2 (O0:0/2 on 1762-L24BXB, 1762-L40BXB and 1764-28BXB) or output 3 (O0:0/3 on 1764-28BXB only).

The interface to the PTO sub-system is accomplished by scanning a PTO instruction in the main program file (file number 2) or by scanning a PTO instruction in any of the subroutine files. A typical operating sequence of a PTO instruction is as follows:

1. The rung that a PTO instruction is on is solved true.

2. The PTO instruction is started, and pulses are produced based on the accelerate/decelerate (ACCEL) parameters, which define the number of ACCEL pulses and the type of profile: s-curve or trapezoid.

3. The ACCEL phase completes.

4. The RUN phase is entered and the number of pulses defined for RUN are output.

5. The RUN phase completes.

6. Decelerate (DECEL) is entered, and pulses are produced based on the accelerate/decelerate parameters, which define the number of DECEL pulses and the type of profile: s-curve or trapezoid.

7. The DECEL phase completes.


Using High-Speed Outputs 6-3

8. The PTO instruction is DONE.

While the PTO instruction is being executed, status bits and information are updated as the main controller continues to operate. Because the PTO instruction is actually being executed by a parallel system, status bits and other information are updated each time the PTO instruction is scanned while it is running. This provides the control program access to PTO status while it is running.

NOTE

PTO status is only as fresh as the scan time of the controller. Worst case latency is the same as the maximum scan of the controller. This condition can be minimized by placing a PTO instruction in the STI (selectable timed interrupt) file, or by adding PTO instructions to your program to increase how often a PTO instruction is scanned.

The charts in the following examples illustrate the typical timing sequence/behavior of a PTO instruction. The stages listed in each chart have nothing to do with controller scan time. They simply illustrate a sequence of events. In actuality, the controller may have hundreds or thousands of scans within each of the stages illustrated in the examples.

Conditions Required to Start the PTO

The following conditions must exist to start the PTO:

•

The PTO instruction must be in an idle state.

•

For idle state behavior, all of the following conditions must be met:

– Jog Pulse (JP) bit must be off

– Jog Continuous (JC) bit must be off

– Enable Hard Stop (EH) bit must be off

– Normal Operation (NS) bit must be off

– The output cannot be forced

•

The rung it is on must transition from a False state (0) to a True state

(1).



Stage

Rung State

Sub-Elements:

Normal Operation/NO

Accelerate Status/AS

Run Status/RS

Decelerate Status/DS

Enable/EN

Done/DN

Idle/ID

Jog Pulse/JP

Jog Continuous/JC

Momentary Logic Enable Example

In this example, the rung state is a momentary or transitional type of input. This means that the false-to-true rung transition enables the PTO instruction and then returns to a false state prior to the PTO instruction completing its operation.

If a transitional input to the PTO instruction is used, the Done (DN) bit turns on when the instruction completes, but only remains on until the next time the PTO instruction is scanned in the user program. The structure of the control program determines when the DN bit goes off. So, to detect when the PTO instruction completes its output, you can monitor the Done (DN), Idle (ID), or Normal Operation (NO) status bits.

0 1 2 3 4 5 6 7 8 9 10 11 12

Relative Timing

Start of PTO Start of PTO


Stage

Rung State

Sub-Elements:

Normal Operation /NO

Accelerate Status /AS

Run Status /RS

Decelerate Status /DS

Enable /EN

Done /DN

Idle /ID

Jog Pulse /JP

Jog Continuous /JC


Standard Logic Enable Example

In this example, the rung state is a maintained type of input. This means that it enables the PTO instruction Normal Operation (NO) and maintains its logic state until after the PTO instruction completes its operation. With this type of logic, status bit behavior is as follows:

The Done (DN) bit becomes true (1) when the PTO completes and remains set until the PTO rung logic is false. The false rung logic re-activates the PTO instruction. To detect when the PTO instruction completes its output, monitor the done (DN) bit.

0 1 2 3 4 5 6 7 8 9 10 11 12

Relative Timing

Start of PTO

Start of PTO



Pulse Train Outputs

(PTO) Function File

Within the RSLogix 500 Function File Folder, you see a PTO Function File with two elements, PTO0 (1762-L24BXB, 1762-L40BXB, and 1764-28BXB) and PTO1 (1764-28BXB only). These elements provide access to PTO configuration data and also allow the control program access to all information pertaining to each of the Pulse Train Outputs.

NOTE

If the controller mode is run, the data within sub-element fields may be changing.




Function File

Sub-Elements Summary

The variables within each PTO sub-element, along with what type of behavior and access the control program has to those variables, are listed individually below. All examples illustrate PTO 0. Terms and behavior for

PTO 1 (MicroLogix 1500 only) are identical.

Table 6.2 Pulse Train Output Function File (PTO:0)

Sub-Element Description

OUT - Output

DN - Done

DS - Decelerating Status

RS - Run Status

AS - Accelerating Status

RP - Ramp Profile

IS - Idle Status

ED - Error Detected Status

NS - Normal Operation Status

JPS - Jog Pulse Status

Address Data

Format

Range

PTO:0.OUT

word (INT) 2 or 3

PTO:0/DN

PTO:0/DS

PTO:0/RS bit bit bit

0 or 1

0 or 1

0 or 1

PTO:0/AS

PTO:0/RP

PTO:0/IS

PTO:0/ED

PTO:0/NS

PTO:0/JPS bit bit bit bit bit bit

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

JCS - Jog Continuous Status

JP - Jog Pulse

JC - Jog Continuous

EH - Enable Hard Stop

EN - Enable Status (follows rung state)

ER - Error Code

PTO:0/JCS

PTO:0/JP

PTO:0/JC

PTO:0/EH

PTO:0/EN

PTO:0.ER

bit bit bit

0 or 1

0 or 1

0 or 1 bit bit

0 or 1

0 or 1 word (INT) -2 to 7

OF - Output Frequency (Hz)

OFS - Operating Frequency Status (Hz)

JF - Jog Frequency (Hz)

TOP - Total Output Pulses To Be Generated

OPP - Output Pulses Produced

ADP - Accel/Decel Pulses

CS - Controlled Stop

PTO:0.OF

PTO:0.OFS

PTO:0.JF

PTO:0.TOP

PTO:0.OPP

PTO:0/CS word (INT) 0 to 20,000 word (INT) 0 to 20,000 word (INT) 0 to 20,000 long word

(32-bit INT) long word

(32-bit INT)

PTO:0.ADP

long word

(32-bit INT) bit

0 to

2,147,483,647

0 to

2,147,483,647

see p. 6-13

0 or 1


Access

For More

Information

control read only

6-8

status read only status read only status read only status read only control read/write status read only

6-8

6-8

6-9

6-9

6-9

6-10

status read only status read only status read only status read only control read/write control read/write control read/write status read only status read only control read/write status read only control read/write control read/write

6-11

6-11

6-17

6-11

6-12

6-15

6-12

6-10

6-15

6-15

6-16

6-15

6-11

status read only control read/write control read/write

6-12

6-13

6-14



PTO Output (OUT)

Sub-Element

Description


OUT - Output PTO:0.OUT word (INT)

Range

2 or 3


Access

control read only

The PTO OUT (Output) variable defines the output (O0:0/2 or O0:0/3) that the PTO instruction controls. This variable is set within the function file folder when the control program is written and cannot be set by the user program.

•

When OUT = 2, PTO pulses output 2 (O0:0.0/2) of the embedded outputs (1762-L24BXB, 1762-L40BXB, and 1764-28BXB).

•

When OUT = 3, PTO pulses output 3 (O0:0.0/3) of the embedded outputs (1764-28BXB only).

NOTE

Forcing an output controlled by the PTO while it is running stops all output pulses and causes a PTO error.

PTO Done (DN)

Sub-Element

Description

DN - Done

Address Data Format Range Type User Program

Access

PTO:0/DN bit 0 or 1 status read only

The PTO DN (Done) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program. The

DN bit operates as follows:

•

Set (1) - Whenever a PTO instruction has completed its operation successfully.

•

Cleared (0) - When the rung the PTO is on is false. If the rung is false when the PTO instruction completes, the Done bit is set until the next scan of the PTO instruction.

PTO Decelerating Status (DS)

Sub-Element

Description


DS - Decelerating Status PTO:0/DS bit

Range

0 or 1

Type

status

User Program

Access

read only

The PTO DS (Decel) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program. The

DS bit operates as follows:

•

Set (1) - Whenever a PTO instruction is within the deceleration phase of the output profile.

•

Cleared (0) - Whenever a PTO instruction is not within the deceleration phase of the output profile.



PTO Run Status (RS)

Sub-Element

Description

Address

RS - Run Status PTO:0/RS

Data Format

bit


Access

0 or 1 status read only

The PTO RS (Run Status) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program.

The RS bit operates as follows:

•

Set (1) - Whenever a PTO instruction is within the run phase of the output profile.

•

Cleared (0) - Whenever a PTO instruction is not within the run phase of the output profile.

PTO Accelerating Status (AS)

Sub-Element

Description

Address Data

Format

AS - Accelerating Status PTO:0/AS bit


Access


The PTO AS (Accelerating Status) bit is controlled by the PTO sub-system.

It can be used by an input instruction on any rung within the control program. The AS bit operates as follows:

•

Set (1) - Whenever a PTO instruction is within the acceleration phase of the output profile.

•

Cleared (0) - Whenever a PTO instruction is not within the acceleration phase of the output profile.

PTO Ramp Profile (RP)

Sub-Element

Description

Address Data Format Range

RP - Ramp Profile PTO:0/RP bit 0 or 1


Access

control read/write

The PTO RP (Ramp Profile) bit controls how the output pulses generated by the PTO sub-system accelerate to and decelerate from the Output

Frequency that is set in the PTO function file (PTO:0.OF). It can be used by an input or output instruction on any rung within the control program.

The RP bit operates as follows:

•

Set (1) - Configures the PTO instruction to produce an S-Curve profile.

•

Cleared (0) - Configures the PTO instruction to produce a Trapezoid profile.



PTO Idle Status (IS)

Sub-Element

Description

IS - Idle Status


Access

PTO:0/IS bit 0 or 1 status read only

The PTO IS (Idle Status) is controlled by the PTO sub-system. It can be used in the control program by an input instruction. The PTO sub-system must be in an idle state whenever any PTO operation needs to start.

The IS bit operates as follows:

•

Set (1) - PTO sub-system is in an idle state. The idle state is defined as the PTO is not running and no errors are present.

•

Cleared (0) - PTO sub-system is not in an idle state (it is running)

PTO Error Detected (ED)

Sub-Element

Description


ED - Error Detected Status PTO:0/ED bit 0 or 1

Type

status

User Program

Access

read only

The PTO ED (Error Detected Status) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program to detect when the PTO instruction is in an error state. If an error state is detected, the specific error is identified in the error code register (PTO:0.ER). The ED bit operates as follows:

•

Set (1) - Whenever a PTO instruction is in an error state

•

Cleared (0) - Whenever a PTO instruction is not in an error state

PTO Normal Operation Status (NS)

Sub-Element Description Address Data Format Range Type User Program

Access

NS - Normal Operation Status PTO:0/NS bit 0 or 1 status read only

The PTO NS (Normal Operation Status) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program to detect when the PTO is in its normal state. A normal state is ACCEL, RUN, DECEL or DONE, with no PTO errors. The NS bit operates as follows:

•

Set (1) - Whenever a PTO instruction is in its normal state

•

Cleared (0) - Whenever a PTO instruction is not in its normal state



PTO Enable Hard Stop (EH)

Sub-Element

Description


EH - Enable Hard Stop PTO:0/EH bit

Range

0 or 1

Type

control

User Program

Access

read/write

The PTO EH (Enable Hard Stop) bit is used to stop the PTO sub-system immediately. Once the PTO sub-system starts a pulse sequence, the only way to stop generating pulses is to set the enable hard stop bit. The enable hard stop aborts any PTO sub-system operation (idle, normal, jog continuous or jog pulse) and generates a PTO sub-system error. The EH bit operates as follows:

•

Set (1) - Instructs the PTO sub-system to stop generating pulses immediately (output off = 0)

•

Cleared (0) - Normal operation

PTO Enable Status (EN)

Sub-Element

Description

EN - Enable Status

(follows rung state)


Access

PTO:0/EN bit 0 or 1 status read only

The PTO EN (Enable Status) is controlled by the PTO sub-system. When the rung preceding the PTO instruction is solved true, the PTO instruction is enabled and the enable status bit is set. If the rung preceding the PTO instruction transitions to a false state before the pulse sequence completes its operation, the enable status bit resets (0). The EN bit operates as follows:

•

Set (1) - PTO is enabled

•

Cleared (0) - PTO has completed, or the rung preceding the PTO is false

PTO Output Frequency (OF)

Sub-Element Description Address Data

Format


Access

OF - Output Frequency (Hz) PTO:0.OF word (INT) 0 to 20,000 control read/write

The PTO OF (Output Frequency) variable defines the frequency of the

PTO output during the RUN phase of the pulse profile. This value is typically determined by the type of device that is being driven, the mechanics of the application, or the device/components being moved.

Data less than zero and greater than 20,000 generates a PTO error.



PTO Operating Frequency Status (OFS)

Sub-Element

Description

OFS - Operating

Frequency Status (Hz)


Access

PTO:0.OFS

word (INT) 0 to 20,000 status read only

The PTO OFS (Output Frequency Status) is generated by the PTO sub-system and can be used in the control program to monitor the actual frequency being produced by the PTO sub-system.

NOTE

The value displayed may not exactly match the value entered in the PTO:0.OF. This is because the PTO sub-system may not be capable of reproducing an exact frequency at some of the higher frequencies. For PTO applications, this is typically not an issue because, in all cases, an exact number of pulses are produced.

PTO Total Output Pulses To Be Generated (TOP)

Sub-Element

Description

Address Data

Format

TOP - Total Output

Pulses To Be Generated

PTO:0.TOP long word

(32-bit INT)

Range Type User

Program

Access

0 to 2,147,483,647 control read/write

The PTO TOP (Total Output Pulses) defines the total number of pulses to be generated for the pulse profile (accel/run/decel inclusive).

PTO Output Pulses Produced (OPP)

Sub-Element

Description

OPP - Output

Pulses Produced

Address Data

Format

PTO:0.OPP

long word

(32-bit INT)


Access

0 to 2,147,483,647 status read only

The PTO OPP (Output Pulses Produced) is generated by the PTO sub-system and can be used in the control program to monitor how many pulses have been generated by the PTO sub-system.



PTO Accel / Decel Pulses (ADP)

Sub-Element

Description


Access

ADP - Accel/Decel

Pulses

PTO:0.ADP

long word (32-bit

INT) see below control read/write

The PTO ADP (Accel/Decel Pulses) defines how many of the total pulses

(TOP variable) will be applied to each of the ACCEL and DECEL components.

The illustration below shows the relationship, where:

•

TOP (total output pulses) = 12,000

•

ADP (accelerate/decelerate pulses)= 3,000

If you need to determine the ramp period (accelerate/decelerate ramp duration):

•

2 x ADP/OF = duration in seconds (OF = output frequency)

The following formulas can be used to calculate the maximum frequency limit for both profiles. The maximum frequency = the integer

≤

the result found below (OF = output frequency):

•

For Trapezoid Profiles: OF x OF/4 + 0.5

•

For S-Curve Profiles: 0.999 x OF x SQRT(OF/6)

Accel Run Decel

Accel

3,000

12,000

Run

6,000

Decel

3,000

The ADP range is from 0 to the calculated value. The value in the ADP variable must be less than one-half the value in the TOP variable, or an error is generated. In this example, the maximum value that could be used for accelerate/decelerate is 6000, because if both accelerate and decelerate are 6000, the total number of pulses = 12,000. The run component would be zero. This profile would consist of an acceleration phase from 0 to 6000. At 6000, the output frequency (OF variable) is generated and immediately enters the deceleration phase, 6000 to 12,000.

At 12,000, the PTO operation would stop (output frequency = 0).



PTO Controlled Stop (CS)


Format

CS - Controlled Stop PTO:0/CS bit


Access

0 or 1 control read/write

The PTO CS (Controlled Stop) bit is used to stop an executing PTO instruction, in the run portion of the profile, by immediately starting the decel phase. Once set, the decel phase completes without an error or fault condition.

Normal Ramp Function without CS

Accel Run

Controlled

Stop (CS) Set

Decel

Ramp Function

Decel After CS is Set

Normal Ramp

Function

Accel Run Decel

If the CS bit is set during the accel phase, the accel phase completes and the PTO immediately enters the decel phase.

Controlled

Stop (CS) Set

Accel

Ramp Function

Decel After CS is Set

Decel

Normal Ramp

Function



PTO Jog Frequency (JF)

Sub-Element

Description

Address Data

Format


Access

JF - Jog Frequency (Hz) PTO:0.JF

word (INT) 0 to 20,000 control read/write

The PTO JF (Jog Frequency) variable defines the frequency of the PTO output during all Jog phases. This value is typically determined by the type of device that is being driven, the mechanics of the application, or the device/components being moved). Data less than zero and greater than 20,000 generates a PTO error.

PTO Jog Pulse (JP)

Sub-Element

Description

JP - Jog Pulse

Address

PTO:0/JP

Data Format

bit

Range

0 or 1


Access

control read/write

The PTO JP (Jog Pulse) bit is used to instruct the PTO sub-system to generate a single pulse. The width is defined by the Jog Frequency parameter in the PTO function file. Jog Pulse operation is only possible under the following conditions:

•

PTO sub-system in idle

•

Jog continuous not active

•

Enable not active

The JP bit operates as follows:

•

Set (1) - Instructs the PTO sub-system to generate a single Jog Pulse

•

Cleared (0) - Arms the PTO Jog Pulse sub-system

PTO Jog Pulse Status (JPS)

Sub-Element

Description

Address Data

Format

JPS - Jog Pulse Status PTO:0/JPS bit


Access


The PTO JPS (Jog Pulse Status) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program to detect when the PTO has generated a Jog Pulse.

The JPS bit operates as follows:

•

Set (1) - Whenever a PTO instruction outputs a Jog Pulse

•

Cleared (0) - Whenever a PTO instruction exits the Jog Pulse state

NOTE

The output (jog) pulse is normally complete with the JP bit set. The JPS bit remains set until the JP bit is cleared (0

= off).



PTO Jog Continuous (JC)

Sub-Element

Description

JC - Jog Continuous


PTO:0/JC bit 0 or 1


Access

control read/write

The PTO JC (Jog Continuous) bit instructs the PTO sub-system to generate continuous pulses. The frequency generated is defined by the Jog

Frequency parameter in the PTO function file. Jog Continuous operation is only possible under the following conditions:

•

PTO sub-system in idle

•

Jog Pulse not active

•

Enable not active

The JC bit operates as follows:

•

Set (1) - Instructs the PTO sub-system to generate continuous Jog

Pulses

•

Cleared (0) - The PTO sub-system does not generate Jog Pulses

When the Jog Continuous bit is cleared, the current output pulse is truncated.

PTO Jog Continuous Status (JCS)


Format

JCS - Jog Continuous Status PTO:0/JCS bit


Access


The PTO JCS (Jog Continuous Status) bit is controlled by the PTO sub-system. It can be used by an input instruction on any rung within the control program to detect when the PTO is generating continuous Jog

Pulses. The JCS bit operates as follows:

•

Set (1) - Whenever a PTO instruction is generating continuous Jog

Pulses

•

Cleared (0) - Whenever a PTO instruction is not generating continuous Jog Pulses.



PTO Error Code (ER)

Sub-Element

Description

ER - Error Code


PTO:0.ER

word (INT) -2 to 7


Access

status read only

PTO ER (Error Codes) detected by the PTO sub-system are displayed in this register. The error codes are shown in the table below:

Table 6.3 Pulse Train Output Error Codes

0

1

Error

Code

-2

-1

2

3

4

5

6

7

Non-User

Fault

Recoverable

Fault

Instruction

Errors

Error

Name

Yes No No

Yes

---

No

---

No

Description

Overlap

Error

Output

Error

An output overlap is detected. Multiple functions are assigned to the same physical output. This is a configuration error. The controller faults and the

User Fault Routine does not execute. Example: PTO0 and PTO1 are both attempting to use a single output.

An invalid output has been specified. Output 2 and output 3 are the only valid choices. This is a configuration error. The controller faults and the User Fault

Routine does not execute.

Normal Normal (0 = no error present)

No No Yes

No

No

No

Yes

Yes

No

Hardstop

Detected

Output

Forced

Error

This error is generated whenever a hard stop is detected. This error does not fault the controller.

To clear this error, scan the PTO instruction on a false rung and reset the EH

(Enable Hard Stop) bit to 0.

The configured PTO output (2 or 3) is currently forced. The forced condition

must be removed for the PTO to operate.

This error does not fault the controller. It is automatically cleared when the force condition is removed.

Frequency

Error

The operating frequency value (OFS) is less than 0 or greater than 20,000.

This error faults the controller. It can be cleared by logic within the User Fault

Routine.

No Yes No

No

No

No

No

Yes

Yes

Yes

No

No

Accel/

Decel

Error

The accelerate/decelerate parameters (ADP) are:

•

•

• less than zero greater than half the total output pulses to be generated (TOP)

Accel/Decel exceeds limit (See page 6-13.)


Routine.

Jog Error PTO is in the idle state and two or more of the following are set:

•

•

•

Enable (EN) bit set

Jog Pulse (JP) bit set

Jog Continuous (JC) bit set

This error does not fault the controller. It is automatically cleared when the error condition is removed.

Jog

Frequency

Error

The jog frequency (JF) value is less than 0 or greater than 20,000. This error faults the controller. It can be cleared by logic within the User Fault Routine.

Length

Error

The total output pulses to be generated (TOP) is less than zero. This error faults the controller. It can be cleared by logic within the User Fault Routine.



PWM - Pulse Width

Modulation

Pulse Width Modulation

PWM Number 1

PWM Function

IMPORTANT

The PWM function can only be used with the controller’s embedded I/O. It cannot be used with expansion I/O modules.

IMPORTANT

The PWM instruction should only be used with MicroLogix

1200 and 1500 BXB units. Relay outputs are not capable of performing very high-speed operations.


Table 6.4 Execution Time for the PWM Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

126.6

µ s

107.4

µ s

False

24.7

µ s

21.1

µ s

The PWM function allows a field device to be controlled by a PWM wave form. The PWM profile has two primary components:

•

Frequency to be generated

•

Duty Cycle interval

The PWM instruction, along with the HSC and PTO functions, are different than all other controller instructions. Their operation is performed by custom circuitry that runs in parallel with the main system processor. This is necessary because of the high performance requirements of these instructions.

The interface to the PWM sub-system is accomplished by scanning a PWM instruction in the main program file (file number 2), or by scanning a

PWM instruction in any of the subroutine files. A typical operating sequence of a PWM instruction is as follows:

1. The rung that a PWM instruction is on is solved true (the PWM is started).

2. A waveform at the specified frequency is produced.

3. The RUN phase is active. A waveform at the specified frequency with the specified duty cycle is output.

4. The rung that the PWM is on is solved false.

5. The PWM instruction is IDLE.

While the PWM instruction is being executed, status bits and data are updated as the main controller continues to operate. Because the PWM


Using High-Speed Outputs 6-19 instruction is actually being executed by a parallel system, the status bits and other information are updated each time the PWM instruction is scanned while it is running. This provides the control program access to

PWM status while it is running.

NOTE

PWM status is only as fresh as the scan time of the controller. Worst case latency is the maximum scan of the controller. This condition can be minimized by placing a

PWM instruction in the STI (selectable timed interrupt) file, or by adding PWM instructions to your program to increase how often a PWM instruction is scanned.

Pulse Width Modulation

(PWM) Function File

Within the PWM function file are two PWM elements. Each element can be set to control either output 2 (O0:0/2 on 1762-L24BXB, 1762-L40BXB, and 1764-28BXB) or output 3 (O0:0/3 on 1764-28BXB only). Function file element PWM:0 is shown below.



Pulse Width Modulated

Function File Elements

Summary

Element Description

The variables within each PWM element, along with what type of behavior and access the control program has to those variables, are listed individually below.

OUT - PWM Output

DS - Decelerating Status

RS - PWM Run Status

AS - Accelerating Status

PP - Profile Parameter Select

IS - PWM Idle Status

ED - PWM Error Detection

NS - PWM Normal Operation

EH - PWM Enable Hard Stop

ES - PWM Enable Status

OF - PWM Output Frequency

OFS - PWM Operating Frequency Status

DC - PWM Duty Cycle

DCS - PWM Duty Cycle Status

ADD - Accel/Decel Delay

ER - PWM Error Codes

Address

PWM:0/PP

PWM:0/IS

PWM:0/ED

PWM:0/NS

PWM:0/EH

PWM:0/ES

PWM:0.OF

PWM:0.OFS

Data Format Range

PWM:0.OUT

word (INT) 2 or 3

PWM:0/DS bit 0 or 1

PWM:0/RS

PWM:0/AS bit bit bit bit bit bit bit bit

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1


Access

status status read only read only status read only status read only control status read/write read only status read only status read only control status read/write read only word (INT) 0 to 20,000 control read/write word (INT) 0 to 20,000 status read only

PWM:0.DC

word (INT) 1 to 1000 control read/write

PWM:0.DCS

word (INT) 1 to 1000 status read only

PWM:0.ADD


PWM:0.ER

word (INT) -2 to 5 status read only

6-22

6-23

6-23

6-23

6-24

6-24

6-24

6-24

6-25

6-25

For More

Information

6-20

6-21

6-21

6-21

6-22

6-22

PWM Output (OUT)

Element

Description

Address Data

Format

Range Type User Program Access

OUT - PWM Output PWM:0.OUT word (INT) 2 or 3 status read only

The PWM OUT (Output) variable defines the physical output that the

PWM instruction controls. This variable is set within the function file folder when the control program is written and cannot be set by the user program. The outputs are defined as O0:0/2 or O0:0/3 as listed below:

•

O0:0.0/2: PWM modulates output 2 of the embedded outputs

(1762-L24BXB, 1762-L40BXB, and 1764-28BXB)

•

O0:0.0/3: PWM modulates output 3 of the embedded outputs

(1764-28BXB only)



PWM Decelerating Status (DS)

Element Description Address Data Format Range Type User Program

Access

DS - Decelerating Status PWM:0/DS bit 0 or 1 status read only

The PWM DS (Decel) bit is controlled by the PWM sub-system. It can be used by an input instruction on any rung within the control program. The

DS bit operates as follows:

•

Set (1) - Whenever a PWM output is within the deceleration phase of the output profile.

•

Cleared (0) - Whenever a PWM output is not within the deceleration phase of the output profile.

PWM Run Status (RS)


Access

RS - PWM Run Status PWM:0/RS bit 0 or 1 status read only

The PWM RS (Run Status) bit is controlled by the PWM sub-system. It can be used by an input instruction on any rung within the control program.

•

Set (1) - Whenever the PWM instruction is within the run phase of the output profile.

•

Cleared (0) - Whenever the PWM instruction is not within the run phase of the output profile.

PWM Accelerating Status (AS)


Access

AS - Accelerating Status PWM:0/AS bit 0 or 1 status read only

The PWM AS (Accelerating Status) bit is controlled by the PWM sub-system. It can be used by an input instruction on any rung within the control program. The AS bit operates as follows:

•

Set (1) - Whenever a PWM output is within the acceleration phase of the output profile.

•

Cleared (0) - Whenever a PWM output is not within the acceleration phase of the output profile.



PWM Profile Parameter Select (PP)


Access

PP - Profile Parameter Select PWM:0/PP bit 0 or 1 control read/write

The PWM PP (Profile Parameter Select) selects which component of the waveform is modified during a ramp phase:

•

Set (1) - selects Frequency

•

Cleared (0) - selects Duty Cycle

The PWM PP bit cannot be modified while the PWM output is running/

enabled. See PWM ADD on page 6-25 for more information.

PWM Idle Status (IS)


Access

IS - PWM Idle Status PWM:0/IS bit 0 or 1 status read only

The PWM IS (Idle Status) is controlled by the PWM sub-system and represents no PWM activity. It can be used in the control program by an input instruction.

•

Set (1) - PWM sub-system is in an idle state.

•

Cleared (0) - PWM sub-system is not in an idle state (it is running).

PWM Error Detected (ED)

Element Description Address Data

Format

ED - PWM Error Detection PWM:0/ED bit


Access


The PWM ED (Error Detected) bit is controlled by the PWM sub-system. It can be used by an input instruction on any rung within the control program to detect when the PWM instruction is in an error state. If an error state is detected, the specific error is identified in the error code register (PWM:0.ED).

•

Set (1) - Whenever a PWM instruction is in an error state.

•

Cleared (0) - Whenever a PWM instruction is not in an error state.



PWM Normal Operation (NS)


Format

NS - PWM Normal Operation PWM:0/NS bit


Access


The PWM NS (Normal Operation) bit is controlled by the PWM sub-system. It can be used by an input instruction on any rung within the control program to detect when the PWM is in its normal state. A normal state is defined as ACCEL, RUN, or DECEL with no PWM errors.

•

Set (1) - Whenever a PWM instruction is in its normal state.

•

Cleared (0) - Whenever a PWM instruction is not in its normal state.

PWM Enable Hard Stop (EH)


Format

EH - PWM Enable Hard Stop PWM:0/EH bit


Access


The PWM EH (Enable Hard Stop) bit stops the PWM sub-system immediately. A PWM hard stop generates a PWM sub-system error.

•

Set (1) - Instructs the PWM sub-system to stop its output modulation immediately (output off = 0).

•

Cleared (0) - Normal operation.

PWM Enable Status (ES)


Access

ES - PWM Enable Status PWM:0/ES bit 0 or 1 status read only

The PWM ES (Enable Status) is controlled by the PWM sub-system. When the rung preceding the PWM instruction is solved true, the PWM instruction is enabled, and the enable status bit is set. When the rung preceding the PWM instruction transitions to a false state, the enable status bit is reset (0) immediately.

•

Set (1) - PWM is enabled.

•

Cleared (0) - PWM has completed or the rung preceding the PWM is false.



PWM Output Frequency (OF)


Format


Access

OF - PWM Output Frequency PWM:0.OF word (INT) 0 to 20,000 control read/write

The PWM OF (Output Frequency) variable defines the frequency of the

PWM function. This frequency can be changed at any time.

PWM Operating Frequency Status (OFS)


OFS - PWM Operating

Frequency Status

Address Data

Format


Access

PWM:0.OFS

word (INT) 0 to 20,000 status read only

The PWM OFS (Output Frequency Status) is generated by the PWM sub-system and can be used in the control program to monitor the actual frequency produced by the PWM sub-system.

PWM Duty Cycle (DC)


DC - PWM Duty Cycle

Address

PWM:0.DC

Data Format

word (INT)


Access

1 to 1000 control read/write

The PWM DC (Duty Cycle) variable controls the output signal produced by the PWM sub-system. Changing this variable in the control program changes the output waveform. Typical values and output waveform:

•

DC = 1000: 100% Output ON (constant, no waveform)

•

DC = 750: 75% Output ON, 25% output OFF

•


•


•

DC = 0: 0% Output OFF (constant, no waveform)

PWM Duty Cycle Status (DCS)


Format


Access

DCS - PWM Duty Cycle Status PWM:0.DCS word (INT) 1 to 1000 status read only

The PWM DCS (Duty Cycle Status) provides feedback from the PWM sub-system. The Duty Cycle Status variable can be used within an input instruction on a rung of logic to provide PWM system status to the remaining control program.



PWM Accel/Decel Delay (ADD)


Access

ADD - Accel/Decel Delay PWM:0.ADD word (INT) 0 to 32,767 control read/write

PWM ADD (Accel/Decel Delay) defines the amount of time in 10 millisecond intervals to ramp from zero to the specified frequency or duration. Also specifies the time to ramp down to zero.

The PWM ADD value is loaded and activated immediately (whenever the

PWM instruction is scanned on a true rung of logic). This allows multiple steps or stages of acceleration or deceleration to occur.

PWM Error Code (ER)


Access

ER - PWM Error Codes PWM:0.ER

word (INT) -2 to 5 status read only

PWM ER (Error Codes) detected by the PWM sub-system are displayed in this register. The table identifies known errors.

0

1

4

5

Error

Code

-2

-1

2

3

Non-User

Fault

Yes

Yes

No

No

Yes

Recoverable

Fault

Instruction

Errors

No No

No

No

No

Yes

No

Yes

Yes

No

Error

Name

Overlap

Error

Output

Error

Description

An output overlap is detected. Multiple functions are assigned to the same physical output. This is a configuration error. The controller faults and the

User Fault Routine does not execute. Example: PWM0 and PWM1 are both attempting to use a single output.

An invalid output has been specified. Output 2 and output 3 are the only valid choices. This is a configuration error. The controller faults and the User Fault

Routine does not execute.

Normal Normal (0 = no error present)

Hardstop

Error

This error is generated whenever a hardstop is detected. This error does not fault the controller. It is automatically cleared when the hardstop condition is removed.

Output

Forced

Error

Frequency

Error

The configured PWM output (2 or 3) is currently forced. The forced condition

must be removed for the PWM to operate. This error does not fault the controller. It is automatically cleared when the force condition is removed.

The frequency value is less than 0 or greater than 20,000. This error faults the controller. It can be cleared by logic within the User Fault Routine.

Reserved

Yes Yes No Duty Cycle

Error

The PWM duty cycle is either less than zero or greater than 1000.


Routine.




1

Chapter

7

Relay-Type (Bit) Instructions

Use relay-type (bit) instructions to monitor and/or control bits in a data file or function file, such as input bits or timer control-word bits. The following instructions are described in this chapter:

Instruction


XIO - Examine if Open

OTE - Output Enable

OTL - Output Latch

OTU - Output Unlatch

ONS - One Shot

OSR - One Shot Rising

OSF - One Shot Falling

Used To:

Examine a bit for an ON condition

Examine a bit for an OFF condition

Turn ON or OFF a bit (non-retentive)

Latch a bit ON (retentive)

Unlatch a bit OFF (retentive)

Detect an OFF to ON transition

Detect an OFF to ON transition

Detect an ON to OFF transition

7-4

7-4

7-5

7-6

7-6

Page

7-1

7-1

7-3

These instructions operate on a single bit of data. During operation, the processor may set or reset the bit, based on logical continuity of ladder rungs. You can address a bit as many times as your program requires.

XIC - Examine if Closed

XIO - Examine if Open

B3:0

0

B3:0

0

Instruction Type: input

Table 7.1 Execution Time for the XIC and XIO Instructions

Controller When Instruction Is:

True

MicroLogix 1200 0.9

µ s

MicroLogix 1500 0.9

µ s

False

0.8

µ s

0.7

µ s

Use the XIC instruction to determine if the addressed bit is on. Use the

XIO instruction to determine if the addressed bit is off.

When used on a rung, the bit address being examined can correspond to the status of real world input devices connected to the base unit or


7-2 Relay-Type (Bit) Instructions expansion I/O, or internal addresses (data or function files). Examples of devices that turn on or off:

• a push button wired to an input (addressed as I1:0/4)

• an output wired to a pilot light (addressed as O0:0/2)

• a timer controlling a light (addressed as T4:3/DN)

• a bit in the bit file (addressed as B3/16)

The instructions operate as follows:

Table 7.2 XIO and XIC Instruction Operation

Rung State

True

True

False

Addressed

Bit

Off

On

--

XIC Instruction

Returns a False

Returns a True

Instruction is not evaluated

XIO Instruction

Returns a True

Returns a False

Instruction is not evaluated

Addressing Modes and File Types can be used as shown in the following table:

Table 7.3 XIC and XIO Instructions Valid Addressing Modes and File Types

For definitions of the terms used in this table see Using the Instruction Descriptions on page4-2.

Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Operand Bit • • • • • • • • • • • • • • • • • • • • • • •

(1) DAT files are valid for the MicroLogix 1500 only. PTO and PWM files are only recommended for use with MicroLogix

1200 and 1500 BXB units.

(2) The Data Log Status file can only be used by the MicroLogix 1500 1764-LRP Processor.


IMPORTANT

You cannot use indirect addressing with: S, ST, MG, PD, RTC,

HSC, PTO, PWM, STI, EII, BHI, MMI, DAT, TPI, CS, IOS, and

DLS files.


Relay-Type (Bit) Instructions 7-3

OTE - Output Energize

B3:0

1


Table 7.4 Execution Time for the OTE Instructions


True

MicroLogix 1200 1.4

µ s

MicroLogix 1500 1.2

µ s

False

1.1

0.0

µ

µ s s

Use an OTE instruction to turn a bit location on when rung conditions are evaluated as true and off when the rung is evaluated as false. An example of a device that turns on or off is an output wired to a pilot light

(addressed as O0:0/4). OTE instructions are reset (turned OFF) when:

•

You enter or return to the program or remote program mode or power is restored.

•

The OTE is programmed within an inactive or false Master Control

Reset (MCR) zone.

NOTE

A bit that is set within a subroutine using an OTE instruction remains set until the OTE is scanned again.

ATTENTION

!



ATTENTION

!

Never use an output address at more than one place in your logic program. Always be fully aware of the load represented by the output coil.


7-4 Relay-Type (Bit) Instructions


Table 7.5 OTE Instruction Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Destination Bit • • • • • • • • • • • • • • • • • •





IMPORTANT



IOS, and DLS files.

OTL - Output Latch

OTU - Output Unlatch

B3:0

L

1

B3:0

L

1


Table 7.6 Execution Time for the OTL and OTU Instructions

Controller OTL - When Rung Is:

True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 0.9

µ s

False

0.0

µ s

0.0

µ s

OTU - When Rung Is:

True

1.1

µ s

0.9

µ s

False

0.0

0.0

µ

µ s s

The OTL and OTU instructions are retentive output instructions. OTL turns on a bit, while OTU turns off a bit. These instructions are usually used in pairs, with both instructions addressing the same bit.

ATTENTION

!



Since these are latching outputs, once set (or reset), they remain set (or reset) regardless of the rung condition.

ATTENTION

!

In the event of a power loss, any OTL controlled bit

(including field devices) energizes with the return of power if the OTL bit was set when power was lost.



ATTENTION

!

Under error conditions, physical outputs are turned off.

Once the error conditions are cleared, the controller resumes operation using the data table value.


Table 7.7 OTL and OTU Instructions Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Address

Level

Parameter

Operand Bit • • • • • • • • • • • • • • • • • •





IMPORTANT



IOS, and DLS files.

ONS - One Shot

N7:1

ONS

0


Table 7.8 Execution Time for the ONS Instructions


True

MicroLogix 1200 2.6 µs

MicroLogix 1500 2.2 µs

False

1.9 µs

1.7 µs

NOTE

The ONS instruction for the MicroLogix 1200 and 1500 provides the same functionality as the OSR instruction for the MicroLogix 1000 and SLC 500 controllers.

The ONS instruction is a retentive input instruction that triggers an event to occur one time. After the false-to-true rung transition, the ONS instruction remains true for one program scan. The output then turns OFF and remains OFF until the logic preceding the ONS instruction is false

(this re-activates the ONS instruction).



The ONS Storage Bit is the bit address that remembers the rung state from the previous scan. This bit is used to remember the false-to-true rung transition.

Table 7.9 ONS Instruction Operation

Rung Transition

false-to-true (one scan)

Storage Bit

storage bit is set true-to-true storage bit remains set true-to-false, false-to-false storage bit is cleared

Rung State after Execution

true false false


Table 7.10 ONS Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Storage Bit • • • •

OSR - One Shot Rising

OSF - One Shot Falling

One Shot Rising

Storage Bit

Output Bit

B3:0/0

B3:0/1

One Shot Falling

Storage Bit

Output Bit

B3:0/0

B3:0/1


Table 7.11 Execution Time for the OSR and OSF Instructions

Controller

MicroLogix 1200

MicroLogix 1500

OSR - When Rung Is:

True

3.4 µs

3.2 µs

False

3.0 µs

2.8 µs

OSF - When Rung Is:

True

2.8 µs

2.7 µs

False

3.7 µs

3.4 µs

NOTE

The OSR instruction for the MicroLogix 1200 and 1500

does not provide the same functionality as the OSR instruction for the MicroLogix 1000 and SLC 500 controllers. For the same functionality as the OSR instruction for the MicroLogix 1000 and SLC 500 controllers, use the ONS instruction.



Use the OSR and OSF instructions to trigger an event to occur one time.

These instructions trigger an event based on a change of rung state, as follows:

•

Use the OSR instruction when an event must start based on the false-to-true (rising edge) change of state of the rung.

•

Use the OSF instruction when an event must start based on the true-to-false (falling edge) change of state of the rung.

These instructions use two parameters, Storage Bit and Output Bit.

•

Storage Bit - This is the bit address that remembers the rung state from the previous scan.

•

Output Bit - This is the bit address which is set based on a false-to-true (OSR) or true-to-false (OSF) rung transition. The Output

Bit is set for one program scan.

To re-activate the OSR, the rung must become false. To re-activate the

OSF, the rung must become true.

Table 7.12 OSR Storage and Output Bit Operation

Rung State Transition

false-to-true (one scan) true-to-true true-to-false and false-to-false

Storage Bit

bit is set bit is set bit is reset

Output Bit

bit is set bit is reset bit is reset

Table 7.13 OSF Storage and Output Bits Operation

Rung State Transition

true-to-false (one scan) false-to-false false-to-true and true-to-true

Storage Bit

bit is reset bit is reset bit is set

Output Bit

bit is set bit is reset bit is reset


Table 7.14 OSR and OSF Instructions Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Storage Bit

Output Bit • •

• •

• • • •

•

•

•

•




1

Chapter

8

Timer and Counter Instructions

Timer Instructions

Overview

Timers and counters are output instructions that let you control operations based on time or a number of events. The following Timer and Counter

Instructions are described in this chapter:

Instruction

TON - Timer, On-Delay

TOF - Timer, Off-Delay

RTO - Retentive Timer On

CTU - Count Up

CTD - Count Down

RES - Reset

Used To:

Delay turning on an output on a true rung

Page

8-4

Delay turning off an output on a false rung

8-5

Delay turning on an output from a true rung.

The accumulator is retentive.

8-6

Count up

Count down

8-9

8-9

Reset the RTO and counter’s ACC and status bits (not used with TOF timers).

8-10

For information on using the High-Speed Counter output(s), see Using the

High-Speed Counter on page 5-1.

Timers in a controller reside in a timer file. A timer file can be assigned as any unused data file. When a data file is used as a timer file, each timer element within the file has three sub-elements. These sub-elements are:

•

Timer Control and Status

•

Preset - This is the value that the timer must reach before the timer times out. When the accumulator reaches this value, the DN status bit is set (TON and RTO only). The preset data range is from 0 to 32767.

The minimum required update interval is 2.55 seconds regardless of the time base.

•

Accumulator - The accumulator counts the time base intervals. It represents elapsed time. The accumulator data range is from 0 to

32767.

Timers can be set to any one of three time bases:

Table 8.1 Timer Base Settings

Time Base

0.001 seconds

0.01 seconds

1.00 seconds

Timing Range

0 to 32.767 seconds

0 to 327.67 seconds

0 to 32,767 seconds


8-2 Timer and Counter Instructions

Each timer address is made of a 3-word element. Word 0 is the control and status word, word 1 stores the preset value, and word 2 stores the accumulated value.

Table 8.2 Timer File

Word Bit

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0 EN TT DN Internal Use

Word 1 Preset Value

Word 2 Accumulated Value

EN = Timer Enable Bit

TT = Timer Timing Bit

DN = Timer Done Bit

ATTENTION

Do not copy timer elements while the timer enable bit

(EN) is set. Unpredictable machine operation may occur.

!


Table 8.3 Timer Instructions Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Timer

Time Base

Preset

Accumulator

(1) Valid for Timer Files only.

NOTE

•

•

•

•

•

•

•

Use an RES instruction to reset a timer’s accumulator and status bits.

•

•


Timer and Counter Instructions 8-3

Timer Accuracy

Timer accuracy refers to the length of time between the moment a timer instruction is enabled and the moment the timed interval is complete.

Table 8.4 Timer Accuracy

Time Base

0.001 seconds

0.01 seconds

1.00 seconds

Accuracy

-0.001 to 0.00

-0.01 to 0.00

-1.00 to 0.00

If your program scan can exceed 2.5 seconds, repeat the timer instruction on a different rung (identical logic) in a different area of the ladder code so that the rung is scanned within these limits.

Repeating Timer Instructions

Using the enable bit (EN) of a timer is an easy way to repeat its complex conditional logic at another rung in your ladder program.

NOTE

Timing could be inaccurate if Jump (JMP), Label (LBL),

Jump to Subroutine (JSR), or Subroutine (SBR) instructions skip over the rung containing a timer instruction while the timer is timing. If the skip duration is within 2.5 seconds, no time is lost; if the skip duration exceeds 2.5 seconds, an undetectable timing error occurs. When using subroutines, a timer must be scanned at least every 2.5 seconds to prevent a timing error.



TON - Timer, On-Delay

Timer On Delay

Timer

Time Base

Preset

Accum

T4:0

1.0

0<

0<

EN

DN


Table 8.5 Execution Time for the TON Instructions


True


µ s


µ s

False

3.0

µ s

2.5

µ s

Use the TON instruction to delay turning on an output. The TON instruction begins to count time base intervals when rung conditions become true. As long as rung conditions remain true, the timer increments its accumulator until the preset value is reached. When the accumulator equals the preset, timing stops.

The accumulator is reset (0) when rung conditions go false, regardless of whether the timer has timed out. TON timers are reset on power cycles and mode changes.

Timer instructions use the following control and status bits:

Table 8.6 Timer Control and Status Bits, Timer Word 0 (Data File 4 is configured as a timer file for this example.)

Bit bit 13 - T4:0/DN bit 14 - T4:0/TT bit15 - T4:0/EN

DN - timer done

TT - timer timing

EN - timer enable

Is Set When:

accumulated value

≥ preset value rung state is true and accumulated value < preset value rung state is true

And Remains Set Until One of the

Following Occurs:

rung state goes false

•

• rung state goes false

DN bit is set rung state goes false



TOF - Timer, Off-Delay

Timer Off Delay

Timer

Time Base

Preset

Accum

T4:0

1.0

0<

0<

EN

DN


Table 8.7 Execution Time for the TOF Instructions


True

MicroLogix 1200 2.9

µ s

MicroLogix 1500 2.5

µ s

False

13.0

µ s

10.9

µ s

Use the TOF instruction to delay turning off an output. The TOF instruction begins to count time base intervals when rung conditions become false. As long as rung conditions remain false, the timer increments its accumulator until the preset value is reached.

The accumulator is reset (0) when rung conditions go true, regardless of whether the timer is timed out. TOF timers are reset on power cycles and mode changes.


Table 8.8 Timer Control and Status Bits, Timer Word 0 (Data File 4 is configured as a timer file for this example.)

Bit bit 13 - T4:0/DN DN - timer done

Is Set When:

rung conditions are true



rung conditions go false and the accumulated value is greater than or equal to the preset value

bit 14 - T4:0/TT TT - timer timing

rung conditions are false and accumulated value is less than the preset value rung conditions go true or when the done bit is reset

bit15 - T4:0/EN

EN - timer enable rung conditions are true rung conditions go false

ATTENTION

!

Because the RES instruction resets the accumulated value and status bits, do not use the RES instruction to reset a timer address used in a TOF instruction. If the TOF accumulated value and status bits are reset, unpredictable machine operation may occur.



RTO - Retentive Timer,

On-Delay

Retentive Timer On

Timer

Time Base

Preset

Accum

T4:0

1.0

0<

0<

EN

DN


Table 8.9 Execution Time for the RTO Instructions

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

18.0

µ s

15.8

µ s

False

2.4

µ s

2.2

µ s

Use the RTO instruction to delay turning “on” an output. The RTO begins to count time base intervals when the rung conditions become true. As long as the rung conditions remain true, the timer increments its accumulator until the preset value is reached.

The RTO retains the accumulated value when the following occur:

• rung conditions become false

• you change the controller mode from run or test to program

• the processor loses power

• a fault occurs

When you return the controller to the RUN or TEST mode, and/or the rung conditions go true, timing continues from the retained accumulated value. RTO timers are retained through power cycles and mode changes.


Table 8.10 Counter Control and Status Bits, Timer Word 0 (Data File 4 is configured as a timer file for this example.)

Bit bit 13 - T4:0/DN bit 14 - T4:0/TT bit15 - T4:0/EN

DN - timer done

TT - timer timing

EN - timer enable

Is Set When:

accumulated value

≥ preset value rung state is true and accumulated value < preset value rung state is true



the appropriate RES instruction is enabled

•

• rung state goes false, or

DN bit is set rung state goes false

To reset the accumulator of a retentive timer, use an RES instruction. See

RES - Reset on page 8-10.



How Counters Work

The figure below demonstrates how a counter works. The count value must remain in the range of -32,768 to +32,767. If the count value goes above +32,767, the counter status overflow bit (OV) is set (1). If the count goes below -32,768, the counter status underflow bit (UN) is set (1). A reset (RES) instruction is used to reset (0) the counter.

-32,768 +32,767 0

Count Up

Counter Accumulator Value

Count Down

Underflow Overflow

Using the CTU and CTD Instructions

Counter instructions use the following parameters:

•

Counter - This is the address of the counter within the data file. All counters are 3-word data elements. Word 0 contains the Control and

Status Bits, Word 1 contains the Preset, and Word 2 contains the

Accumulated Value.

Word

Word 0

Word 1

Word 2

Bit

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

CU CD DN OV UN Not Used

Preset Value

Accumulated Value

CU = Count Up Enable Bit

CD = Count Down Enable Bit

DN = Count Done Bit

OV = Count Overflow Bit

UN = Count Underflow Bit

•

Preset - When the accumulator reaches this value, the DN bit is set.

The preset data range is from -32768 to 32767.

•

Accumulator - The accumulator contains the current count. The accumulator data range is from -32768 to 32767.

The accumulated value is incremented (CTU) or decremented (CTD) on each false-to-true rung transition. The accumulated value is retained when the rung condition again becomes false, and when power is cycled on the controller. The accumulated count is retained until cleared by a reset (RES) instruction that has the same address as the counter.



NOTE

The counter continues to count when the accumulator is greater than the CTU preset and when the accumulator is less than the CTD preset.


Table 8.11 CTD and CTU Instructions Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Counter

Preset

Accumulator

(1) Valid for Counter Files only.

•

•

•

•

•

•

•

Using Counter File Control and Status Bits

Like the accumulated value, the counter status bits are also retentive until reset, as described below.

Table 8.12 CTU Instruction Counter Control and Status Bits, Counter Word 0

(Data File 5 is configured as a timer file for this example.)

Bit bit 12 - C5:0/OV bit 15 - C5:0/CU

OV - overflow indicator bit 13 - C5:0/DN DN - done indicator

CU - count up enable

Is Set When: And Remains Set Until One of the Following

Occurs:

the accumulated value wraps from +32,767 to -32,768 and continues to count up a RES instruction with the same address as the CTU instruction is enabled accumulated value rung state is true

≥ preset value

•

•

•

• accumulated value < preset value or, a RES instruction with the same address as the CTU instruction is enabled rung state is false a RES instruction with the same address as the CTU instruction is enabled

Table 8.13 CTD Instruction Counter Control and Status Bits, Counter Word 0

(Data File 5 is configured as a timer file for this example.)

Bit bit 11 - C5:0/UN bit 13 - C5:0/DN bit 14 - C5:0/CD

UN - underflow indicator

DN - done indicator

CD - count down enable

Is Set When: And Remains Set Until One of the Following

Occurs:

the accumulated value wraps from -32,768 to +32,767 and continues to count down accumulated value rung state is true

≥ preset value a RES instruction with the same address as the CTD instruction is enabled

•

•

•

• accumulated value

< preset value or, a RES instruction with the same address as the

CTU instruction is enabled rung state is false a RES instruction with the same address as the

CTD instruction is enabled



CTU - Count Up

CTD - Count Down

Count Up

Counter

Preset

Accum

C5:0

0<

0<

CU

DN

Count Down

Counter

Preset

Accum

C5:0

0<

0<

CU

DN


Table 8.14 Execution Time for the CTU and CTD Instructions

Controller

MicroLogix 1200

MicroLogix 1500

CTU - When Rung Is:

True

9.0

µ s

6.4

µ s

False

9.2

µ s

8.5

µ s

CTD - When Rung Is:

True

9.0

µ s

7.5

µ s

False

9.0

µ s

8.5

µ s

The CTU and CTD instructions are used to increment or decrement a counter at each false-to-true rung transition. When the CTU rung makes a false-to-true transition, the accumulated value is incremented by one count. The CTD instruction operates the same, except the count is decremented.

NOTE

If the signal is coming from a field device wired to an input on the controller, the on and off duration of the incoming signal must not be more than twice the controller scan time (assuming 50% duty cycle). This condition is needed to enable the counter to detect false-to-true transitions from the incoming device.



RES - Reset

R6:0

RES


Table 8.15 Execution Time for the RES Instructions


True

MicroLogix 1200 5.9

µ s

MicroLogix 1500 4.8

µ s

False

0.0

µ s

0.0

µ s

The RES instruction resets timers, counters, and control elements. When the RES instruction is executed, it resets the data defined by the RES instruction.

The RES instruction has no effect when the rung state is false. The following table shows which elements are modified:

Table 8.16 RES Instruction Operation

When using a RES instruction with a:

Timer Element Counter Element

The controller resets the:

ACC value to 0

DN bit

TT bit

EN bit


ACC value to 0

OV bit

UN bit

DN bit

CU bit

CD bit

Control Element


POS value to 0

EN bit

EU bit

DN bit

EM bit

ER bit

UL bit

ATTENTION

!

Because the RES instruction resets the accumulated value and status bits, do not use the RES instruction to reset a timer address used in a TOF instruction. If the TOF accumulated value and status bits are reset, unpredictable machine operation or injury to personnel may occur.


Table 8.17 RES Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Structure • • •


1

Chapter

9

Compare Instructions

Use these input instructions when you want to compare values of data.

Instruction

EQU - Equal

NEQ - Not Equal

LES - Less Than

LEQ - Less Than or Equal To

GRT - Greater Than

Used To:

Test whether two values are equal (=)

Page

9-3

Test whether one value is not equal to a second value (

≠

)

Test whether one value is less than a second value (<)

9-3

9-4

Test whether one value is less than or equal to a second value (

≤

)

9-5

Test whether one value is greater than a second value (>)

9-4

GEQ - Greater Than or Equal To Test whether one value is greater than or equal to a second value (

≥

)

MEQ - Mask Compare for Equal Test portions of two values to see whether they are equal

LIM - Limit Test

9-5

9-6

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

9-7


9-2 Compare Instructions

Using the Compare

Instructions

Most of the compare instructions use two parameters, Source A and

Source B (MEQ and LIM have an additional parameter and are described later in this chapter). Both sources cannot be immediate values. The valid data ranges for these instructions are:

-32768 to 32767 (word)

-2,147,483,648 to 2,147,483,647 (long word)

IMPORTANT

Only use the High Speed Counter Accumulator (HSC.ACC) for Source A in GRT, LES, GEQ and LEQ instructions.


Table 9.1 EQU, NEQ, GRT, LES, GEQ and LEQ Instructions

Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Source A

Source B

• • • • • •

• • • • • •

• • • • • • • • • • • • • •

• • •

• •

• • • • • • • • • • • • •

• •

• •





IMPORTANT



IOS, and DLS files.


Compare Instructions 9-3

EQU - Equal

NEQ - Not Equal

Equal

Source A

Source B

N7:0

N7:1

0<

0<

Not Equal

Source A

Source B

N7:0

0<

N7:1

0<


Table 9.2 Execution Time for the EQU and NEQ Instructions

Controller

MicroLogix 1200

MicroLogix 1500

Instruction

EQU

NEQ

EQU

NEQ

Data Size

word long word word long word word long word word long word

When Rung Is:

True

1.3

µ s

2.8

µ s

1.3

µ s

2.5

µ s

1.2

µ s

2.6

µ s

1.2

µ s

2.3

µ s

False

1.1

µ s

1.9

µ s

1.1

µ s

2.7

µ s

1.1

µ s

1.9

µ s

1.1

µ s

2.5

µ s

The EQU instruction is used to test whether one value is equal to a second value. The NEQ instruction is used to test whether one value is not equal to a second value.

Table 9.3 EQU and NEQ Instruction Operation

Instruction Relationship of Source Values

EQU A = B

A

≠

B

NEQ A = B

A

≠

B

Resulting Rung State

true false false true



GRT - Greater Than

LES - Less Than

Greater Than (A>B)

Source A N7:0

Source B N7:1

0<

0<

Less Than (A<B)

Source A

Source B

N7:0

0<

N7:1

0<


Table 9.4 Execution Time for the GRT and LES Instructions


MicroLogix 1200 word

MicroLogix 1500 long word word long word

When Rung Is:

True

1.3

µ s

2.8

µ s

1.2

µ s

2.6

µ s

False

1.1

µ s

2.7

µ s

1.1

µ s

2.5

µ s

The GRT instruction is used to test whether one value is greater than a second value. The LES instruction is used to test whether one value is less than a second value.

Table 9.5 GRT and LES Instruction Operation


GRT

LES

A > B

A

≤

A

≥

B

B

A

<

B



IMPORTANT




GEQ - Greater Than or

Equal To

LEQ - Less Than or Equal

To

Grtr Than or Eql (A>=B)

Source A N7:0

0<

Source B N7:1

0<

Less Than or Eql (A<=B)

Source A N7:0

0<

Source B N7:1

0<


Table 9.6 Execution Time for the GEQ and LEQ Instructions




When Rung Is:

True

1.3

µ s

2.8

µ s

1.2

µ s

2.6

µ s

False

1.1

µ s

2.7

µ s

1.1

µ s

2.5

µ s

The GEQ instruction is used to test whether one value is greater than or equal to a second value. The LEQ instruction is used to test whether one value is less than or equal to a second value.

Table 9.7 GEQ and LEQ Instruction Operation


GEQ A

≥

B

A < B

LEQ A > B

A

≤

B



IMPORTANT




MEQ - Mask Compare for Equal

Masked Equal

Source

Mask

Compare

N7:0

N7:1

0<

0000h<

N7:2

0<


Table 9.8 Execution Time for the MEQ Instructions




When Rung Is:

True

1.9

µ s

3.9

µ s

1.7

µ s

3.5

µ s

False

1.8

µ s

3.1

µ s

1.7

µ s

2.9

µ s

The MEQ instruction is used to compare whether one value (source) is equal to a second value (compare) through a mask. The source and the compare are logically ANDed with the mask. Then, these results are compared to each other. If the resulting values are equal, the rung state is true. If the resulting values are not equal, the rung state is false.

For example:

Source: Compare:

1 1 1 1 1 0 1 0 0 0 0 0 1 1 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0

Mask: Mask:

1 1 0 0 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 1 1 1 1 0 0 0 0 1 1

Intermediate Result: Intermediate Result:

1 1 0 0 1 0 1 0 0 0 0 0 0 0 0 0 1 1 0 0 1 1 1 1 0 0 0 0 0 0 0 0

Comparison of the Intermediate Results: not equal

The source, mask, and compare values must all be of the same data size

(either word or long word). The data ranges for mask and compare are:

•

-32768 to 32767 (word)

•

-2,147,483,648 to 2,147,483,647 (long word)

The mask is displayed as a hexadecimal unsigned value from 0000 to

FFFF FFFF.




Table 9.9 MEQ Instruction Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Address

Level

Parameter

Source

Mask

Compare

• • • • • •

• • • • • •

• • • • • •

• • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• •

• •

• •





IMPORTANT



IOS, and DLS files.

LIM - Limit Test

Limit Test

Low Lim

Test

High Lim

N7:0

0<

0

N7:1

0<

0<


Table 9.10 Execution Time for the LIM Instructions

Controller

MicroLogix 1200

MicroLogix 1500

Data Size

word long word word long word

When Rung Is:

True

6.4

µ s

14.4

µ s

5.5

µ s

12.2

µ s

False

6.1

µ s

13.6

µ s

5.3

µ s

11.7

µ s

The LIM instruction is used to test for values within or outside of a specified range. The LIM instruction is evaluated based on the Low Limit,

Test, and High Limit values as shown in the following table.

Table 9.11 LIM Instruction Operation Based on Low Limit, Test, and High Limit Values

When:

Low Limit

≤

High Limit

Low Limit

≤

High Limit

High Limit < Low Limit

High Limit < Low Limit

And:

Low Limit

≤

Test

≤

High Limit

Test < Low Limit or Test > High Limit

High Limit < Test

<

Low Limit

Test

≥

High Limit or Test

≤

Low Limit

Rung State




The Low Limit, Test, and High Limit values can be word addresses or constants, restricted to the following combinations:

•

If the Test parameter is a constant, both the Low Limit and High Limit parameters must be word or long word addresses.

•

If the Test parameter is a word or long word address, the Low Limit and High Limit parameters can be either a constant, a word, or a long word address. But the Low Limit and High Limit parameters cannot both be constants.

When mixed-sized parameters are used, all parameters are put into the format of the largest parameter. For instance, if a word and a long word are used, the word is converted to a long word.

The data ranges are:

•

-32768 to 32767 (word)

•

-2,147,483,648 to 2,147,483,647 (long word)


Table 9.12 LIM Instruction Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Low Limit

Test

High Limit

• • • • • •

• • • • • •

• • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• •

• •

• •





IMPORTANT



IOS, and DLS files.


1

Chapter

10

Math Instructions

Use these output instructions to perform computations using an expression or a specific arithmetic instruction.

Instruction

ADD - Add

SUB - Subtract

MUL - Multiply

Used To:

Add two values

Subtract two values

Multiply two values

Page

10-4

10-4

10-5

DIV - Divide

NEG - Negate

CLR - Clear

SQR - Square Root

Divide one value by another

Change the sign of the source value and place it in the destination

Set all bits of a word to zero

Find the square root of a value

10-5

10-6

10-6

10-9

SCL - Scale

SCP - Scale with Parameters

Scale a value

10-7

Scale a value to a range determined by creating a linear relationship

10-8

10-10

SWP - Swap

(cannot be used with MicroLogix

1200 and 1500 Series A

controllers)

Swap low byte with high byte in a specified number of words


10-2 Math Instructions

Using the Math

Instructions

Most math instructions use three parameters, Source A, Source B, and

Destination (additional parameters are described where applicable, later in this chapter). The mathematical operation is performed using both

Source values. The result is stored in the Destination.

When using math instructions, observe the following:

•

Source and Destination can be different data sizes. Sources are evaluated at the highest precision (word or long word) of the operands. Then the result is converted to the size of the destination. If the signed value of the Source does not fit in the Destination, the overflow shall be handled as follows:

– If the Math Overflow Selection Bit is clear, a saturated result is stored in the Destination. If the Source is positive, the Destination is +32767 (word) or +2,147,483,647 (long word). If the result is negative, the Destination is -32768 (word) or -2,147,483,648 (long word).

– If the Math Overflow Selection Bit is set, the unsigned truncated value of the Source is stored in the Destination.

•

Sources can be constants or an address, but both sources cannot be constants.

•

Valid constants are -32768 to 32767 (word) and -2,147,483,648 to

2,147,483,647 (long word).


Table 10.1 Math Instructions Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Source A

Source B

• • • • • •

• • • • • •

Destination • • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • •

• •

• •

• •



(2) The Data Log Status file can only be used by the MicroLogix 1500 1764-LRP Processor for the following math instructions: ADD, SUB, MUL, DIV, NEG, and SCP.


IMPORTANT



IOS, and DLS files.


Math Instructions 10-3

Updates to Math Status

Bits

After a math instruction is executed, the arithmetic status bits in the status file are updated. The arithmetic status bits are in word 0 in the processor status file (S2).

Table 10.2 Math Status Bits

With this Bit:

S:0/0

Carry

S:0/1

Overflow

S:0/2

S:0/3

Zero Bit

Sign Bit

S:2/14

Math Overflow

Selected

(1)

S:5/0

Overflow Trap

(1)

(1) Control bits.

The Controller:

sets if carry is generated; otherwise resets sets when the result of a math instruction does not fit into the destination, otherwise resets sets if result is zero, otherwise resets sets if result is negative (MSB is set), otherwise resets examines the state of this bit to determine the value of the result when an overflow occurs sets if the Overflow Bit is set, otherwise resets

Overflow Trap Bit, S:5/0

Minor error bit (S:5/0) is set upon detection of a mathematical overflow or division by zero. If this bit is set upon execution of an END statement or a

Temporary End (TND) instruction, the recoverable major error code 0020 is declared.

In applications where a math overflow or divide by zero occurs, you can avoid a controller fault by using an unlatch (OTU) instruction with address S:5/0 in your program. The rung must be between the overflow point and the END or TND statement.

The following illustration shows the rung you can use to unlatch the overflow trap bit.

S:5

U

0



ADD - Add

SUB - Subtract

Add

Source A

Source B

Dest

N7:0

N7:1

0<

N7:2

0<

0<

Subtract

Source A

Source B

Dest

N7:0

N7:1

0<

N7:2

0<

0<


Table 10.3 Execution Time for the ADD and SUB Instructions

Controller

MicroLogix 1200

MicroLogix 1500

Instruction

ADD

SUB

ADD

SUB

Data Size


When Rung Is:

True

2.7

µ s

11.9

µ s

3.4

µ s

12.9

µ s

2.5

µ s

10.4

µ s

2.9

µ s

11.2

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

Use the ADD instruction to add one value to another value (Source A +

Source B) and place the sum in the Destination.

Use the SUB instruction to subtract one value from another value (Source

A - Source B) and place the result in the Destination.



MUL - Multiply

DIV - Divide

Multiply

Source A

Source B

Dest

N7:0

N7:1

0<

N7:2

0<

0<

Divide

Source A

Source B

Dest

N7:0

N7:1

0<

N7:2

0<

0<


Table 10.4 Execution Time for the MUL and DIV Instructions

Controller

MicroLogix 1200

MicroLogix 1500

Instruction

MUL

DIV

MUL

DIV

Data Size


When Rung Is:

True

6.8

µ s

31.9

µ s

12.2

µ s

42.8

µ s

5.8

µ s

27.6

µ s

10.3

µ s

36.7

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

0.1

µ s

0.0

µ s

0.0

µ s

Use the MUL instruction to multiply one value by another value (Source A x Source B) and place the result in the Destination.

Use the DIV instruction to divide one value by another value (Source A/

Source B) and place the result in the Destination. If the Sources are single words and the Destination is directly addressed to S:13 (math register), then the quotient is stored in S:14 and the remainder is stored in S:13. If long words are used, then the results are rounded.



NEG - Negate

Negate

Source

Dest

N7:0

0<

N7:1

0<


Table 10.5 Execution Time for the NEG Instruction




When Rung Is:

True

2.9

µ s

12.1

µ s

1.9

µ s

10.4

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

Use the NEG instruction to change the sign of the Source and place the result in the Destination.

CLR - Clear

Clear

Dest N7:0

0<


Table 10.6 Execution Time for the CLR Instruction

Controller

MicroLogix 1200

MicroLogix 1500

Data Size


When Rung Is:

True

1.3

µ s

6.3

µ s

1.2

µ s

5.5

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

Use the CLR instruction to set the Destination to a value of zero.



SCL - Scale

Scale

Source

Rate [/10000]

Offset

Dest

N7:0

0<

N7:1

N7:2

0<

N7:3

0<

0<


Table 10.7 Execution Time for the SCL Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

10.5

µ s

8.7

µ s

False

0.0

µ s

0.0

µ s

The SCL instruction causes the value at the Source address to be multiplied by the Rate (slope) value. The resulting value is added to the

Offset and the rounded result is placed in the Destination.

The following equations express the linear relationship between the input value and the resulting scaled value: scaled value = [(rate x source)/10000] + offset, where

• rate = (scaled max. - scaled min.)/(input max. - input min.)

• offset = scaled min. - (input min. x rate)

Rate and Offset can both be immediate values. The data range for rate and offset is -32768 to 32767.


Table 10.8 SCL Instruction Valid Addressing Modes and File Types



Address

(1)

Mode

Parameter

Address

Level

Source

Rate

Offset

Destination

• •

• •

• •

• •

• • •

• • •

• • •

• • •


• •

• • •

• • •

• •

•

•

•

•

IMPORTANT



IOS, and DLS files.

IMPORTANT

Do not use the High Speed Counter Accumulator

(HSC.ACC) for the Destination parameter in the SCL instruction.



SCP - Scale with

Parameters

Scale w/Parameters

Input

Input Min.

Input Max.

Scaled Min.

Scaled Max.

Output

N7:0

0<

N7:1

N7:2

0<

N7:3

0<

0<

N7:4

0<

N7:5

0<


Table 10.9 Execution Time for the SCP Instruction




When Rung Is:

True

31.5

µ s

52.2

µ s

27.0

µ s

44.7

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The SCP instruction produces a scaled output value that has a linear relationship between the input and scaled values. This instruction solves the following equation listed below to determine scaled output: y = [(y

1

- y

0

)/(x

1

- x

0

)](x - x

0

) + y

0


Table 10.10 SCP Instruction Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(2)

Address

Level

Parameter

Input (x) • • • • • •

Input Min. (x

0

)

Output (y)

• •

Input Max. (x

1

)

• •

Scaled Min. (y

0

)

• •

Scaled Max. (y

1

)

• •

• • •

• • •

• • •

• • •

• • • • • •

• • • • • • • • • • • • •

•

•

•

•

• • • • • • •

• •

• • •

• • •

• • •

• • •

• •

• •

• •

• •

• •

• •

• •




IMPORTANT



IOS, and DLS files.

IMPORTANT


(HSC.ACC) for the Scaled Output parameter in the SCP instruction.



SQR - Square Root

Square Root

Source

Dest

N7:0

0<

N7:1

0<


Table 10.11 Execution Time for the SQR Instruction




When Rung Is:

True

26.0

µ s

30.9

µ s

22.3

µ s

26.0

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The SQR instruction calculates the square root of the absolute value of the source and places the rounded result in the destination.

The data ranges for the source is -32768 to 32767 (word) and

-2,147,483,648 to 2,147,483,647 (long word). The Carry Math Status Bit is

set if the source is negative. See Updates to Math Status Bits on page 10-3

for more information.

Table 10.12 SQR Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source • •

Destination • •

• • •

• • •

•

•


• • •

• •

• •

• •

IMPORTANT



IOS, and DLS files.



SWP - Swap

Swap

Source

Length

#ST10:1.DATA[0]

13


Table 10.13 Execution Time for the SWP Instruction


True False

MicroLogix 1200 Series B and higher 13.7

µ s + 2.2

µ s/swapped word 0.0

µ s

MicroLogix 1500 Series B and higher 11.7

µ s + 1.8

µ s/swapped word 0.0

µ s

Use the SWP instruction to swap the low and high bytes of a specified number of words in a bit, integer, or string file. The SWP instruction has 2 operands:

•

Source is the word address containing the words to be swapped.

•

Length is the number of words to be swapped, regardless of the file type. The address is limited to integer constants. For bit and integer filetypes, the length range is 1 to 128. For the string filetype, the length range is 1 to 41. Note that this instruction is restricted to a single string element and cannot cross a string element boundary.




Table 10.14 SWP Instruction Valid Addressing Modes and File Types



Address

(1)

Mode

Parameter

Address

Level

Source

Length

• • •


•

• •

•

IMPORTANT



IOS, and DLS files.

Example:

Swap

Source

Length

#ST10:1.DATA[0]

13

Source Value before executing SWP instruction: a b c d e f g h i j k l m n o p q r s t u v w x y z a b c d e f g

Source Value before executing SWP instruction: b a d c f e h g j i l k n m p o r q t s v u x w z y a b c d e f g

The underlined characters show the 13 words where the low byte was swapped with the high byte.




1

Chapter

11

Conversion Instructions

The conversion instructions multiplex and de-multiplex data and perform conversions between binary and decimal values.

Instruction

DCD - Decode 4 to 1-of-16

ENC - Encode 1-of-16 to 4

FRD - Convert From Binary

Coded Decimal

TOD - Convert to Binary Coded

Decimal

Used To:

Decodes a 4-bit value (0 to 15), turning on the corresponding bit in the 16-bit destination.

Page

11-2

Encodes a 16-bit source to a 4-bit value.

Searches the source from the lowest to the highest bit and looks for the first set bit. The corresponding bit position is written to the destination as an integer.

11-3

Converts the BCD source value to an integer and stores it in the destination.

11-4

Converts the integer source value to BCD format and stores it in the destination.

11-8

Using Decode and

Encode Instructions


Table 11.1 Conversion Instructions Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source

Destination

• •

• •

• • •

• • •


• •

• •

•

•

IMPORTANT



IOS, and DLS files.


11-2 Conversion Instructions

DCD - Decode 4 to

1-of-16

Decode 4 to 1 of 16

Source N7:0

0000h<

Dest N7:1

0000000000000000<


Table 11.2 Execution Time for the DCD Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

1.9

µ s

0.9

µ s

False

0.0

µ s

0.0

µ s

The DCD instruction uses the lower four bits of the source word to set one bit of the destination word. All other bits in the destination word are cleared. The DCD instruction converts the values as shown in the table below:

Table 11.3 Decode 4 to 1-of-16

x x x x x x x x

Source Bits Destination Bits

15 to 04 03 02 01 00 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

x x

0

0

0

0

0

0

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

1

0 x x x x

0

0

0

0

0

0

1

1

1

1

0

0

0

1

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

0

0

1

0

0

1

0

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

1

1

1

1

1

1

1

1

0

0

0

0

1

1

1

1

0

0

1

1

0

0

0

1

0

1

0

1

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0 x x

x = not used

1 1 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0


Conversion Instructions 11-3

ENC - Encode

1-of-16 to 4

Encode 1 of 16 to 4

Source N7:0

0000000000000000<

Dest N7:1

0000h<


Table 11.4 Execution Time for the ENC Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

7.2

µ s

6.8

µ s

False

0.0

µ s

0.0

µ s

The ENC instruction searches the source from the lowest to the highest bit, looking for the first bit set. The corresponding bit position is written to the destination as an integer. The ENC instruction converts the values as shown in the table below:

Table 11.5 Encode 1-of-16 to 4

Source Bits Destination Bits

15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 15 to 04 03 02 01 00

x x x x x x x x x x x x x x x x x x x x x x x x x x x x x 1 x x x x x x x 1 0 x x x x x x 1 0 0

0

0

0

0 0 0 0

0 0 0 1

0 0 1 0 x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x

1 x

1

0

1

0

0

0

0

0

0

0

0

0

0

0 x x x x x x x x x x x x x x x x x

1

1

0

0

0

0

0

0

0

0

0

0

0

0

0 x x x x x x x 1 0 0 0 0 0 0 0 0

0

0

0

0

0

0

0

0

0

0

1

1

1

0

0

1

0

1

0 1 1 0

0 1 1 1

1 0 0 0 x x x x x x 1 0 0 0 0 0 0 0 0 0 x x x x x 1 0 0 0 0 0 0 0 0 0 0 x x x x 1 0 0 0 0 0 0 0 0 0 0 0 x x x 1 0 0 0 0 0 0 0 0 0 0 0 0 x x 1 0 0 0 0 0 0 0 0 0 0 0 0 0 x 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0

1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

x = determines the state of the flag

0

0

0

0

0

0

0

1 0 0 1

1 0 1 0

1 0 1 1

1 1 0 0

1 1 0 1

1 1 1 0

1 1 1 1

NOTE

If source is zero, the destination is zero and the math status is zero, the flag is set to 1.

Updates to Math Status Bits


With this Bit:

S:0/0

Carry

S:0/1

The Controller:

always resets

Overflow sets if more than one bit in the source is set; otherwise resets. The math overflow bit (S:5/0) is not set.

S:0/2

S:0/3

Zero Bit sets if result is zero, otherwise resets

Sign Bit always resets



FRD - Convert from

Binary Coded Decimal

(BCD)

From BCD

Source

Dest

S:0

0000h<

N7:0

0<


Table 11.7 Execution Time for the FRD Instructions

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

14.1

µ s

12.3

µ s

False

0.0

µ s

0.0

µ s

The FRD instruction is used to convert the Binary Coded Decimal (BCD) source value to an integer and place the result in the destination.


Table 11.8 FRD Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source • • • • • •

Destination • • • • •


(2) See FRD Instruction Source Operand on page 11-5.

• •

• •

•

•

(2)

IMPORTANT



IOS, and DLS files.



FRD Instruction Source Operand

The source can be either a word address or the math register. The maximum BCD source values permissible are:

•

9999 if the source is a word address (allowing only a 4-digit BCD value)

•

32768 if the source is the math register (allowing a 5-digit BCD value with the lower 4 digits stored in S:13 and the high order digit in S:14).

If the source is the math register, it must be directly addressed as S:13.

S:13 is the only status file element that can be used.



With this Bit:

S:0/0

Carry

S:0/1

Overflow

S:0/2

S:0/3

Zero Bit

Sign Bit

The Controller:

always resets sets if non-BCD value is contained at the source or the value to be converted is greater than 32,767; otherwise resets. On overflow, the minor error flag is also set.

sets if result is zero, otherwise resets always resets

NOTE

Always provide ladder logic filtering of all BCD input devices prior to performing the FRD instruction. The slightest difference in point-to-point input filter delay can cause the FRD instruction to overflow due to the conversion of a non-BCD digit.

S:1

]/[

15

EQU

EQUAL

Source A

Source B

N7:1

0

I:0.0

0

FRD

FROM BCD

Source

Dest

I:0.0

0

N7:2

0

MOV

MOVE

Source

Dest

I:0.0

0

N7:1

0

The two rungs shown cause the controller to verify that the value I:0 remains the same for two consecutive scans before it executes the FRD.

This prevents the FRD from converting a non-BCD value during an input value change.



NOTE

To convert numbers larger than 9999 BCD, the source must be the Math Register (S:13). You must reset the

Minor Error Bit (S:5.0) to prevent an error.

Example

The BCD value 32,760 in the math register is converted and stored in

N7:0. The maximum source value is 32767 (BCD).

S:14

0000 0000 0000 0011

15

0 0 0

0

3

From BCD

Source S:13

00032760<

Dest N7:0

32760<

S:13

0010 0111 0110 0000

15

2 7 6

0

0

5-digit BCD

3 2 7 6 0

N7:0 Decimal 0111 1111 1111 1000

You should convert BCD values to integer before you manipulate them in your ladder program. If you do not convert the values, the controller manipulates them as integers and their value may be lost.

NOTE

If the math register (S:13 and S:14) is used as the source for the FRD instruction and the BCD value does not exceed four digits, be sure to clear word S:14 before executing the FRD instruction. If S:14 is not cleared and a value is contained in this word from another math instruction located elsewhere in the program, an incorrect decimal value is placed in the destination word.



Clearing S:14 before executing the FRD instruction is shown below:

I:1

] [

0

MOV

MOVE

Source

Dest

N7:2

4660

S:13

4660

0001 0010 0011 0100

CLR

CLEAR

Dest S:14

0

FRD

FROM BCD

Source

Dest

S:13

00001234

N7:0

1234

S:13 and S:14 are displayed in BCD format.

0000 0100 1101 0010

When the input condition I:0/1 is set (1), a BCD value (transferred from a

4-digit thumbwheel switch for example) is moved from word N7:2 into the math register. Status word S:14 is then cleared to make certain that unwanted data is not present when the FRD instruction is executed.



TOD - Convert to Binary

Coded Decimal (BCD)

To BCD

Source

Dest

N7:0

N7:1

0<

0000h<


Table 11.10 Execution Time for the TOD Instructions

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

17.2

µ s

14.3

µ s

False

0.0

µ s

0.0

µ s

The TOD instruction is used to convert the integer source value to BCD and place the result in the destination.


Table 11.11 TOD Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source

Destination

• • • • •

• • • • • •


(2) See TOD Instruction Destination Operand below.

• •

• •

•

•

(2)

IMPORTANT



DLS files.

TOD Instruction Destination Operand

The destination can be either a word address or math register.

The maximum values permissible once converted to BCD are:

•

9999 if the destination is a word address (allowing only a 4-digit BCD value)

•

32768 if the destination is the math register (allowing a 5-digit BCD value with the lower 4 digits stored in S:13 and the high order digit in

S:14).

If the destination is the math register, it must be directly addressed as S:13.

S:13 is the only status file element that can be used.





With this Bit:

S:0/0

S:0/1

Carry

Overflow

S:0/2

S:0/3

Zero Bit

Sign Bit

The Controller:

always resets sets if BCD result is larger than 9999. On overflow, the minor error flag is also set.

sets if result is zero, otherwise resets sets if the source word is negative; otherwise resets

Changes to the Math Register

Contains the 5-digit BCD result of the conversion. This result is valid at overflow.

NOTE

To convert numbers larger than 9999 decimal, the destination must be the Math Register (S:13). You must reset the Minor Error Bit (S:5/0) to prevent an error.

Example

The integer value 9760 stored at N7:3 is converted to BCD and the BCD equivalent is stored in N7:0. The maximum BCD value is 9999.

To BCD

Source N7:3

9760<

Dest N10:0

9760<

The destination value is displayed in BCD format.

9 7 6 0 N7:3 Decimal

MSB

LSB

0010 0110 0010 0000

9 7 6 0 N7:0 4-digit BCD

1001 0111 0110 0000




1

Using Logical

Instructions

Chapter

12

Logical Instructions

The logical instructions perform bit-wise logical operations on individual words.

Instruction

AND - Bit-Wise AND

OR - Logical OR

XOR - Exclusive OR

NOT - Logical NOT

Used To:

Perform an AND operation

Perform an inclusive OR operation

Perform an Exclusive Or operation

Perform a NOT operation

Page

12-3

12-4

12-5

12-6

When using logical instructions, observe the following:

•

Source and Destination must be of the same data size (i.e. all words or all long words).

IMPORTANT


(HSC.ACC) for the Destination parameter in the AND,

OR, and XOR instructions.

•

Source A and Source B can be a constant or an address, but both cannot be constants.

•


2,147,483,647 (long word).


12-2 Logical Instructions


Table 12.1 Logical Instructions Valid Addressing Modes and File Types


Data Files

Function Files

(1)

Address

Mode

(3)

Parameter

Address

Level

Source A

Source B

(4)

• • • • • •

• • • • • •

• • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • •

• •

• •

Destination • • • • • • • • • • • • •

(1) DAT files are valid for the MicroLogix 1500 only. PTO and PWM files are valid for MicroLogix 1200 and 1500 BXB units.


• • • •


(4) Source B does not apply to the NOT instruction. The NOT instruction only has one source value.

IMPORTANT



IOS, and DLS files.

Updates to Math Status

Bits

After a logical instruction is executed, the arithmetic status bits in the status file are updated. The arithmetic status bits are in word 0 bits 0-3 in the processor status file (S2).


With this Bit:

S:0/0

Carry

S:0/1

S:0/2

S:0/3

Overflow

Zero Bit

Sign Bit

The Controller:

always resets always resets sets if result is zero, otherwise resets sets if result is negative (MSB is set), otherwise resets


Logical Instructions 12-3

AND - Bit-Wise AND

Bitwise AND

Source A

Source B

Dest

N7:0

0000h<

N7:1

0000h<

N7:2

0000h<


Table 12.3 Execution Time for the AND Instruction




When Rung Is:

True

2.2

µ s

9.2

µ s

2.0

µ s

7.9

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The AND instruction performs a bit-wise logical AND of two sources and places the result in the destination.

Table 12.4 Truth Table for the AND Instruction

Destination = A AND B

Source: A

1 1 1 1 1 0 1 0 0 0 0 0 1 1 0 0

Source: B

1 1 0 0 1 1 1 1 1 1 0 0 0 0 1 1

Destination:

1 1 0 0 1 0 1 0 0 0 0 0 0 0 0 0

IMPORTANT


(HSC.ACC) for the Destination parameter in the AND, OR, and XOR instructions.

For more information, see Using Logical Instructions on page 12-1 and

Updates to Math Status Bits on page 12-2.



OR - Logical OR

OR OR

Bitwise Inclusive OR

Source A

Source B

N7:0

0000h<

N7:1

Dest

0000h<

N7:2

0000h<


Table 12.5 Execution Time for the OR Instruction




When Rung Is:

True

2.2

µ s

9.2

µ s

2.0

µ s

7.9

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The OR instruction performs a logical OR of two sources and places the result in the destination.

Table 12.6 Truth Table for the OR Instruction

Destination = A OR B

Source: A

1 1 1 1 1 0 1 0 0 0 0 0 1 1 0 0

Source: B

1 1 0 0 1 1 1 1 1 1 0 0 0 0 1 1

Destination:

1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1

IMPORTANT




Logical Instructions 12-5

XOR - Exclusive OR

Bitwise Exclusive OR

Source A N7:0

Source B

Dest

0000h<

N7:1

0000h<

N7:2

0000h<


Table 12.7 Execution Time for the XOR Instruction




When Rung Is:

True

3.0

µ s

9.9

µ s

2.3

µ s

8.9

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The XOR instruction performs a logical exclusive OR of two sources and places the result in the destination.

Table 12.8 Truth Table for the XOR Instruction

Destination = A XOR B

Source: A

1 1 1 1 1 0 1 0 0 0 0 0 1 1 0 0

Source: B

1 1 0 0 1 1 1 1 1 1 0 0 0 0 1 1

Destination:

0 0 1 1 0 1 0 1 1 1 0 0 1 1 1 1

IMPORTANT







NOT - Logical NOT

NOT

Source

Dest

N7:0

0<

N7:1

0<


Table 12.9 Execution Time for the NOT Instruction




When Rung Is:

True

2.4

µ s

9.2

µ s

2.4

µ s

8.1

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The NOT instruction is used to invert the source bit-by-bit (one’s complement) and then place the result in the destination.

Table 12.10 Truth Table for the NOT Instruction

Destination = A NOT B

Source:

1 1 1 1 1 0 1 0 0 0 0 0 1 1 0 0

Destination:

0 0 0 0 0 1 0 1 1 1 1 1 0 0 1 1




Chapter

13

Move Instructions

The move instructions modify and move words.

Instruction

MOV - Move

MVM - Masked Move

Used to:

Move the source value to the destination.

Move data from a source location to a selected portion of the destination.

Page

13-1

13-3

1

MOV - Move

Move

Source

Dest

N7:0

N7:1

0<

0<


Table 13.1 Execution Time for the MOV Instruction

Controller

MicroLogix 1200

Data Size

word long word


When Rung Is:

True

2.4

µ s

8.3

µ s

2.3

µ s

6.8

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The MOV instruction is used to move data from the source to the destination. As long as the rung remains true, the instruction moves the data each scan.

Using the MOV Instruction

When using the MOV instruction, observe the following:

•

Source and Destination can be different data sizes. The source is converted to the destination size when the instruction executes. If the signed value of the Source does not fit in the Destination, the overflow is handled as follows:

– If the Math Overflow Selection Bit is clear, a saturated result is stored in the Destination. If the Source is positive, the Destination is 32767 (word). If the result is negative, the Destination is -32768.

– If the Math Overflow Selection Bit is set, the unsigned truncated value of the Source is stored in the Destination.

•

Source can be a constant or an address.

•


2,147,483,647 (long word).


13-2 Move Instructions


Table 13.2 MOV Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

(2)

Address

Mode

(4)

Parameter

Address

Level

Source

Destination

• • • • • • • • • • • • • • • • • • • • • • • •

• • • • • • • • •

(5)

(5) (5) (5)

• •

• •

• •

(1) The ST file is not valid for MicroLogix 1500 1764-LSP Series A processors.

(2) DAT files are valid for the MicroLogix 1500 only. PTO and PWM files are valid for MicroLogix 1200 and 1500 BXB units.



(5) Some elements can be written to. Consult the function file for details.

IMPORTANT



IOS, and DLS files.


After a MOV instruction is executed, the arithmetic status bits in the status file are updated. The arithmetic status bits are in word 0 bits 0-3 in the processor status file (S2).


With this Bit:

S:0/0

S:0/1

Carry

Overflow

S:0/2

S:0/3

S:5/0

Zero Bit

Sign Bit

Math Overflow Trap

Bit

(1)

(1) Control bit.

The Controller:

always resets sets when an overflow condition is detected, otherwise resets sets if result is zero, otherwise resets sets if result is negative (MSB is set), otherwise resets sets Math Overflow Trap minor error if the Overflow bit is set, otherwise it remains in last state

NOTE

If you want to move one word of data without affecting the math flags, use a copy (COP) instruction with a length of 1 word instead of the MOV instruction.


Move Instructions 13-3

MVM - Masked Move

Masked Move

Source

Mask

Dest

N7:0

N7:1

0<

0000h<

N7:2

0<


Table 13.4 Execution Time for the MVM Instruction




When Rung Is:

True

7.8

µ s

11.8

µ s

7.2

µ s

10.0

µ s

False

0.0

µ s

0.0

µ s

0.0

µ s

0.0

µ s

The MVM instruction is used to move data from the source to the destination, allowing portions of the destination to be masked. The mask bit functions as follows:

Table 13.5 Mask Function for MVM Instruction

0

1

Source Bit

1

0

Mask Bit

0

0

1

1

Destination Bit

last state last state

1

0

Mask data by setting bits in the mask to zero; pass data by setting bits in the mask to one. The mask can be a constant, or you can vary the mask by assigning a direct address. Bits in the Destination that correspond to zeros in the Mask are not altered.

Using the MVM Instruction

When using the MVM instruction, observe the following:

•

Source, Mask, and Destination must be of the same data size (i.e. all words or all long words).

To mask data, set the mask bit to zero; to pass data, set the mask bit to one. The mask can be a constant value, or you can vary the mask by assigning a direct address.

NOTE

Bits in the destination that correspond to zeros in the mask are not altered as shown in the shaded areas in the following table.


13-4 Move Instructions


Table 13.6 Mask Example (Word Addressing Level)

Word

Value in Destination

Before Move

Source Value

Mask

Value in Destination

After Move

Value in

Hexadecimal

FFFF

5555

F0F0

5F5F

Value in Binary

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

1 1 1 1

1 1

1 1 1 1 1 1 1 1 1 1

0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1

1 1 1 1

0 0

0 0 1 1 1 1 0 0 0 0

0 1 0 1

1 1

1 1 0 1 0 1 1 1 1 1

•

Valid constants for the mask are -32768 to 32767 (word) and

-2,147,483,648 to 2,147,483,647 (long word). The mask is displayed as a hexadecimal unsigned value from 0000 0000 to FFFF FFFF.


Table 13.7 MVM Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

(2)

Parameter

Address

Level

Source

Mask

Destination

• •

• •

• •

• • • • •

• • • • •

• • • • •



• •

• • •

• •

• •

• •

• •

IMPORTANT



DLS files.


After a MVM instruction is executed, the arithmetic status bits in the status file are updated. The arithmetic status bits are in word 0 bits 0-3 in the processor status file (S2).


With this Bit:

S:0/0

Carry

S:0/1

S:0/2

S:0/3

Overflow

Zero Bit

Sign Bit

The Controller:

always resets always resets sets if destination is zero, otherwise resets sets if the MSB of the destination is set, otherwise resets

1

Chapter

14

File Instructions

The file instructions perform operations on file data.

Instruction

COP - Copy File

FLL - Fill File

Used To:

Copy a range of data from one file location to another

Load a file with a program constant or a value from an element address

Page

14-2

14-3

Load and unload data into a bit array one bit at a time

14-4

14-6

BSL - Bit Shift Left

BSR - Bit Shift Right

FFL - First In, First Out (FIFO) Load Load words into a file and unload them in the same order (first in, first out)

FFU - First In, First Out (FIFO)

Unload

14-8

14-11

LFL - Last In, First Out (LIFO) Load Load words into a file and unload them in reverse order (last in, first out)

LFU - Last In, First Out (LIFO)

Unload

14-14

14-17


14-2 File Instructions

COP - Copy File

Copy File

Source

Dest

Length

#N7:0

#N7:1

1


Table 14.1 Execution Time for the COP Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True False

19.08

µ s + 0.8 µs/word 0.0

µ s

15.9

µ s + 0.67 µs/word 0.0

µ s

The COP instruction copies blocks of data from one location into another.

Table 14.2 COP Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

(2)

Parameter

Address

Level

Source

Destination

Length

• •

• •

• • • • •

• • • • •



•

• •

• •

IMPORTANT

You cannot use indirect addressing with: S, MG, PD, RTC,

HSC, PTO, PWM, STI, EII, BHI, MMI, DAT, TPI, CS, IOS, and DLS files.

•

•

The source and destination file types must be the same except bit (B) and integer (N); they can be interchanged. It is the address that determines the maximum length of the block to be copied, as shown in the following table:

Table 14.3 Maximum Lengths for the COP Instruction

Source/Destination Data Type

1 word elements (ie. word)

2 word elements (ie. long word)

3 word elements (ie. counter)

42 word elements (ie. string)

Range of Length Operand

1 to 128

1 to 64

1 to 42

1 to 3


File Instructions 14-3

FLL - Fill File

Fill File

Source

Dest

Length

N7:0

#N7:1

1


Table 14.4 Execution Time for the FLL Instruction




When Rung Is:

True False

14 + 0.6

µ s/word 0.0

µ s

15 + 1.2

µ s/long word 0.0

µ s

12.1 + 0.43

µ s/word 0.0

µ s

12.3 + 0.8

µ s/long word 0.0

µ s

The FLL instruction loads elements of a file with either a constant or an address data value for a given length. The following figure shows how file instruction data is manipulated. The instruction fills the words of a file with a source value. It uses no status bits. If you need an enable bit, program a parallel output that uses a storage address.

Destination

Source

Word to File

This instruction uses the following operands:

•

Source - The source operand is the address of the value or constant used to fill the destination. The data range for the source is from

-32768 to 32767 (word) or -2,147,483,648 to 2,147,483,647 (long word).

NOTE

A constant cannot be used as the source in a timer (T), counter (C), or control (R) file.

•

Destination - The starting destination address where the data is written.

•

Length - The length operand contains the number of elements. The length can range from 1 to 128 (word), 1 to 64 (long word), or 1 to 42

(3 word element such as counter).

NOTE

The source and destination operands must be of the same file type, unless they are bit (B) and integer (N).




Table 14.5 FLL Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source

Destination

Length

• •

• •

• • •

• • •

•

•


• • •

• •

•

• • •

•

IMPORTANT


RTC, HSC, PTO, PWM, STI, EII, BHI, MMI, DATI, TPI, CS,

IOS, and DLS files.

BSL - Bit Shift Left

Bit Shift Left

File

Control

Bit Address

Length

#B3:1

R6:0

B32:0/0

1<

EN

DN


Table 14.6 Execution Time for the BSL Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True False

32

µ s + 1.3

µ s/word 1.3

µ s

26.1

µ s + 1.06

µ s/word 1.4

µ s

The BSL instruction loads data into a bit array on a false-to-true rung transition, one bit at a time. The data is shifted left through the array, then unloaded, one bit at a time. The following figure shows the operation of the BSL instruction.

Source Bit

I:22/12

Data block is shifted one bit at a time from bit 16 to bit 73.

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16

47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32

63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48

RESERVED 73 72 71 70 69 68 67 66 65 64

58 Bit Array #B3:1

Unload Bit

(R6:0/10)



If you wish to shift more than one bit per scan, you must create a loop in your application using the JMP, LBL, and CTU instructions.


•

File - The file operand is the address of the bit array that is to be manipulated.

•

Control - The control operand is the address of the BSL’s control element. The control element consists of 3 words:

Word 0

15 14 13 12

EN

(1) --

DN

(2) --

Word 1

Size of bit array (number of bits).

Word 2

not used

11 10 9 8 7 6 5 4 3 2 1 0

ER

(3)

UL

(4) not used

(1) EN - Enable Bit is set on false-to-true transition of the rung and indicates the instruction is enabled.

(2) DN - Done Bit, when set, indicates that the bit array has shifted one position.

(3) ER - Error Bit, when set, indicates that the instruction detected an error such as entering a negative number for the length or source operand.

(4) UL - Unload Bit is the instruction’s output. Avoid using the UL (unload) bit when the ER (error) bit is set.

•

Bit Address - The source is the address of the bit to be transferred into the bit array at the first (lowest) bit position.

•

Length - The length operand contains the length of the bit array in bits. The valid data range for length is from 0 to 2048.


Table 14.7 BSL Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

File

Control

• • •

(2)

• •

Length

Source • • • • • •


(2) Control file only. Not valid for Timers and Counters.

• •

•

•

• • •

• •

•

•

IMPORTANT


RTC, HSC, PTO, PWM, STI, EII, BHI, MMI, DATI, TPI, CS,

IOS, and DLS files.



BSR - Bit Shift Right

Bit Shift Right

File

Control

Bit Address

Length

#B3:3

R6:0

I:0/15

1<

EN

DN


Table 14.8 Execution Time for the BSR Instruction


True

MicroLogix 1200 32

µ s + 1.3

µ s/word


µ s + 1.07

µ s/word

False

1.3

µ s

1.4

µ s

If you wish to shift more than one bit per scan, you must create a loop in your application using the JMP, LBL, and CTU instructions.

The BSR instruction loads data into a bit array on a false-to-true rung transition, one bit at a time. The data is shifted right through the array, then unloaded, one bit at a time. The following figure shows the operation of the BSR instruction.

Unload Bit

(R6:0/10)

47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32

63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48

INVALID 69 68 67 66 65 64

Data block is shifted one bit at a time from bit 69 to bit 32.

Source Bit

I:23/06

38 Bit Array

#B3:2


•

File - The file operand is the address of the bit array that is to be manipulated.

•

Control - The control operand is the address of the BSR’s control element. The control element consists of 3 words:

Word 0

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

EN

(1)

--

DN

(2)

--

ER

(3)

UL

(4) not used

Word 1

Size of bit array (number of bits).

Word 2

not used


(2) DN - Done Bit, when set, indicates that the bit array has shifted one position.

(3) ER - Error Bit, when set, indicates that the instruction detected an error such as entering a negative number for the length or source operand.

(4) UL - Unload Bit is the instruction’s output. Avoid using the UL (unload) bit when the ER (error) bit is set.



•

Bit Address - The source is the address of the bit to be transferred into the bit array at the last (highest) bit position.

•

Length - The length operand contains the length of the bit array in bits. The data range for length is from 0 to 2048.


Table 14.9 BSR Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

File

Control

• • •

(2)

• •

Length

Source • • • • • •



•

•

•

•

• • •

• •

•

•

IMPORTANT



IOS, and DLS files.



FFL - First In, First Out

(FIFO) Load

FIFO Load

Source

FIFO

Control

Length

Position

N7:0

#N7:1

R6:0

1<

0<

EN

DN

EM

FFL

FIFO LOAD

Source

FIFO

Control

Length

Position

N7:10

#N7:12

R6:0

34

9

(EN)

(DN)

(EM)

FFU

FIFO UNLOAD

FIFO

Dest

Control

Length

Position

#N7:12

N7:11

R6:0

34

9

(EU)

(DN)

(EM)

FFL and FFU Instruction Pair


Table 14.10 Execution Time for the FFL Instruction




When Rung Is:

True

11.3

µ s

11.7

µ s

10.0

µ s

10.9

µ s

False

11.1

µ s

11.2

µ s

9.8

µ s

9.7

µ s

On a false-to-true rung transition, the FFL instruction loads words or long words into a user-created file called a FIFO stack. This instruction’s counterpart, FIFO unload (FFU), is paired with a given FFL instruction to remove elements from the FIFO stack. Instruction parameters have been programmed in the FFL - FFU instruction pair shown below.

Destination

N7:11

FFU instruction unloads data from stack #N7:12 at position 0, N7:12

Source

N7:10

N7:12

N7:13

N7:14

8

9

5

6

3

4

7

1

2

Position

0

34 words are allocated for FIFO stack starting at N7:12, ending at

N7:45

FFL instruction loads data into stack

#N7:12 at the next available position, 9 in this case.

N7:45 33

Loading and Unloading of Stack #N7:12




•

Source - The source operand is a constant or address of the value used to fill the currently available position in the FIFO stack. The address level of the source must match the FIFO stack. If FIFO is a word size file, source must be a word value or constant. If FIFO is a long word size file, source must be a long word value or constant.

The data range for the source is from -32768 to 32767 (word) or

-2,147,483,648 to 2,147,483,647 (long word).

•

FIFO - The FIFO operand is the starting address of the stack.

•

Control - This is a control file address. The status bits, stack length, and the position value are stored in this element. The control element consists of 3 words:

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

EN

(1) --

DN

(2)

EM

(3) not used

Word 1

Length - maximum number of words or long words in the stack.

Word 2

Position - the next available location where the instruction loads data.


(2) DN - Done Bit, when set, indicates that the stack is full.

(3) EM - Empty Bit, when set, indicates FIFO is empty.

•

Length - The length operand contains the number of elements in the

FIFO stack to receive the value or constant found in the source. The length of the stack can range from 1 to 128 (word) or 1 to 64 (long word). The position is incremented after each load.

•

Position - This is the current location pointed to in the FIFO stack. It determines the next location in the stack to receive the value or constant found in source. Position is a component of the control register. The position can range from 0 to 127 (word) or 0 to 63 (long word).




Table 14.11 FFL Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source

FIFO

Control

• •

• •

• • •

•

(2)

•

•

•

Length

Position


(2) Control file only. Not valid for Timers or Counters.

•

•

• • •

• •

•

•

•

• •

• •

•

IMPORTANT



IOS, and DLS files.



FFU - First In, First Out

(FIFO) Unload

FIFO Unload

FIFO

Dest

Control

Length

Position

#N7:0

N7:1

R6:0

1<

0<

EU

DN

EM

FFL

FIFO LOAD

Source

FIFO

Control

Length

Position

N7:10

#N7:12

R6:0

34

9

(EN)

(DN)

(EM)

FFU

FIFO UNLOAD

FIFO

Dest

Control

Length

Position

#N7:12

N7:11

R6:0

34

9

(EU)

(DN)

(EM)

FFL and FFU Instruction Pair


Table 14.12 Execution Time for the FFU Instruction

Controller

MicroLogix 1200

MicroLogix 1500

Data Size When Rung Is:


True False

33

µ s + 0.8

µ s/word

36

µ s + 1.5

µ s/ long word

27.7

µ s + 0.65

µ s/word

10.4

10.4

9.7

µ

µ

µ s

29.4

µ s + 1.25

µ s/long word 9.7

µ s s s

On a false-to-true rung transition, the FFU instruction unloads words or long words from a user-created file called a FIFO stack. The data is unloaded using first-in, first-out order. After the unload completes, the data in the stack is shifted one element toward the top of the stack and the last element is zeroed out. Instruction parameters have been programmed in the FFL - FFU instruction pair shown below.

Destination

N7:11

FFU instruction unloads data from stack #N7:12 at position 0, N7:12

Source

N7:10

N7:12

N7:13

N7:14

8

9

4

5

2

3

6

7

Position

0

1


N7:45

FFL instruction loads data into stack


N7:45 33





•

FIFO - The FIFO operand is the starting address of the stack.

•

Destination - The destination operand is a word or long word address that stores the value which exits from the FIFO stack. The FFU instruction unloads this value from the first location on the FIFO stack and places it in the destination address. The address level of the destination must match the FIFO stack. If FIFO is a word size file, destination must be a word size file. If FIFO is a long word size file, destination must be a long word size file.

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

--

EU

(1)

DN

(2)

EM

(3) not used

Word 1


Word 2

Position - the next available location where the instruction unloads data.

(1) EU - Enable Unload Bit is set on false-to-true transition of the rung and indicates the instruction is enabled.


(3) EM - Empty Bit, when set, indicates FIFO is empty.

•


FIFO stack. The length of the stack can range from 1 to 128 (word) or

1 to 64 (long word).

•

Position - Position is a component of the control register. The position can range from 0 to 127 (word) or 0 to 63 (long word). The position is decremented after each unload. Data is unloaded at position zero.




Table 14.13 FFU Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

FIFO • •

Destination • •

Control

• •

• • •

(2)

•

•

Length

Position



•

•

• •

• •

•

•

•

• •

• •

•

IMPORTANT



IOS, and DLS files.



LFL - Last In, First Out

(LIFO) Load

LIFO Load

Source

LIFO

Control

Length

Position

N7:0

#N7:1

R6:0

1<

0<

EN

DN

EM


Table 14.14 Execution Time for the LFL Instruction




When Rung Is:

True

25.5

µ s

31.6

µ s

22.2

µ s

27.4

µ s

False

10.4

µ s

10.4

µ s

9.7

µ s

9.7

µ s

On a false-to-true rung transition, the LFL instruction loads words or long words into a user-created file called a LIFO stack. This instruction’s counterpart, LIFO unload (LFU), is paired with a given LFL instruction to remove elements from the LIFO stack. Instruction parameters have been programmed in the LFL - LFU instruction pair shown below.

LFL

LIFO LOAD

Source

LIFO

Control

Length

Position

N7:10

#N7:12

R6:0

34

9

(EN)

(DN)

(EM)

LFU

LIFO UNLOAD

LIFO

Dest

Control

Length

Position

#N7:12

N7:11

R6:0

34

9

LFL and LFU Instruction Pair

(EU)

(DN)

(EM)

Destination

N7:11

LFU instruction unloads data from stack #N7:12 at position 0, N7:12

Source

N7:10

N7:12

N7:13

N7:14

8

9

5

6

3

4

7

1

2

Position

0


N7:45

LFL instruction loads data into stack


N7:45 33





•

Source - The source operand is a constant or address of the value used to fill the currently available position in the LIFO stack. The data size of the source must match the LIFO stack. If LIFO is a word size file, source must be a word value or constant. If LIFO is a long word size file, source must be a long word value or constant. The data range for the source is from -32768 to 32767 (word) or -2,147,483,648 to 2,147,483,647 (long word).

•

LIFO - The LIFO operand is the starting address of the stack.

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

EN

(1) --

DN

(2)

EM

(3) not used

Word 1


Word 2

Position - the next available location where the instruction loads data.



(3) EM - Empty Bit, when set, indicates that LIFO is empty.

•


FIFO stack to receive the value or constant found in the source. The length of the stack can range from 1 to 128 (word) or 1 to 64 (long word). The position is incremented after each load.

•

Position - This is the current location pointed to in the LIFO stack. It determines the next location in the stack to receive the value or constant found in source. Position is a component of the control register. The position can range from 0 to 127 (word) or 0 to 63 (long word).




Table 14.15 LFL Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

Source

LIFO

Control

• •

• •

• • •

•

(2)

•

•

•

Length

Position



•

•

• • •

• •

•

•

•

• •

• •

•

IMPORTANT



IOS, and DLS files.



LFU - Last In, First Out

(LIFO) Unload

LIFO Unload

LIFO

Dest

Control

Length

Position

#N7:0

N7:1

R6:0

1<

0<

EU

DN

EM


Table 14.16 Execution Time for the LFU Instruction




When Rung Is:

True

29.1

µ s

31.6

µ s

25.6

µ s

27.4

µ s

False

10.4

µ s

10.4

µ s

9.7

µ s

9.7

µ s

On a false-to-true rung transition, the LFU instruction unloads words or long words from a user-created file called a LIFO stack. The data is unloaded using last-in, first-out order. Instruction parameters have been programmed in the LFL - LFU instruction pair shown below.

LFL

LIFO LOAD

Source

LIFO

Control

Length

Position

N7:10

#N7:12

R6:0

34

9

(EN)

(DN)

(EM)

LFU

LIFO UNLOAD

LIFO

Dest

Control

Length

Position

#N7:12

N7:11

R6:0

34

9

LFL and LFU Instruction Pair

(EU)

(DN)

(EM)

Destination

N7:11

LFU instruction unloads data from stack #N7:12 at position 0, N7:12

N7:12

N7:13

N7:14

8

9

4

5

2

3

6

7

Position

0

1


N7:45

Source

N7:10

LFL instruction loads data into stack


N7:45 33






•

LIFO - The LIFO operand is the starting address of the stack.

•

Destination - The destination operand is a word or long word address that stores the value which exits from the LIFO stack. The LFU instruction unloads this value from the last location on the LIFO stack and places it in the destination address. The address level of the destination must match the LIFO stack. If LIFO is a word size file, destination must be a word size file. If LIFO is a long word size file, destination must be a long word size file.

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

--

EU

(1)

DN

(2)

EM

(3) not used

Word 1

Length - maximum number of words or double words in the stack.

Word 2

Position - the next available location where the instruction unloads data.

(1) EU - Enable Unload Bit is set on false-to-true transition of the rung and indicates the instruction is enabled.


(3) EM - Empty Bit, when set, indicates LIFO is empty.

•


LIFO stack. The length of the stack can range from 1 to 128 (word) or

1 to 64 (long word).

•

Position - This is the next location in the LIFO stack where data will be unloaded. Position is a component of the control register. The position can range from 0 to 127 (word) or 0 to 63 (long word). The position is decremented after each unload.

Table 14.17 LFU Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

LIFO • •

Destination • •

Control

• •

• • •

(2)

•

•

Length

Position



•

•

• •

• •

•

•

•

• •

• •

•

IMPORTANT



IOS, and DLS files.

1

Chapter

15

Sequencer Instructions

Sequencer instructions are used to control automatic assembly machines or processes that have a consistent and repeatable operation. They are typically time based or event driven.

Instruction

SQC - Sequencer Compare

SQO - Sequencer Output

SQL - Sequencer Load

Used To:

Compare 16-bit data with stored data

Transfer 16-bit data to word addresses

Load 16-bit data into a file

Page

15-2

15-5

15-8

Use the sequencer compare instruction to detect when a step is complete; use the sequencer output instruction to set output conditions for each step. Use the sequencer load instruction to load data into the sequencer file.

The primary advantage of sequencer instructions is to conserve program memory. These instructions monitor and control 16 (word) or 32 (long word) discrete outputs at a time in a single rung.

You can use bit integer or double integer files with sequencer instructions.


15-2 Sequencer Instructions

SQC- Sequencer

Compare

Sequencer Compare

File #B3:0

Mask N7:0

Source

Control

Length

Position

I:0.0

R6:0

1<

0<

EN

DN

FD


Table 15.1 Execution Time for the SQC Instruction




When Rung Is:

True

23.5

µ s

26.3

µ s

20.1

µ s

22.7

µ s

False

7.1

µ s

7.1

µ s

6.3

µ s

6.3

µ s

On a false-to-true rung transition, the SQC instruction is used to compare masked source words or long words with the masked value at a reference address (the sequencer file) for the control of sequential machine operations.

When the status of all non-masked bits in the source word match those of the corresponding reference word, the instruction sets the found bit (FD) in the control word. Otherwise, the found bit (FD) is cleared.

The bits mask data when reset (0) and pass data when set (1).

The mask can be fixed or variable. If you enter a hexadecimal code, it is fixed. If you enter an element address or a file address (direct or indirect) for changing the mask with each step, it is variable.

When the rung goes from false-to-true, the instruction increments to the next step (word) in the sequencer file. Data stored there is transferred through a mask and compared against the source for equality. While the rung remains true, the source is compared against the reference data for every scan. If equal, the FD bit is set in the SQCs control counter.

Applications of the SQC instruction include machine diagnostics.


Sequencer Instructions 15-3

The following figure explains how the SQC instruction works.

Sequencer Compare

File #B10:11

Mask FFF0

Source

Control

Length

Position

I:3.0

R6:21

4<

2<

Input Word I:3.0

0010 0100 1001 1101

EN

DN

FD

Mask Value FFF0

1111 1111 1111 0000

Sequencer Ref File #B10:11

Word

B10:11

B10:12 1

B10:13 0010 0100 1001 0000

2

Step

0

B10:14

B10:15

3

4

SQC FD bit is set when the instruction detects that an input word matches

(through mask) its corresponding reference word.

The FD bit R6:21/FD is set in the example, since the input word matches the sequencer reference value using the mask value.




•

File - This is the sequencer reference file. Its contents, on an element-by-element basis, are masked and compared to the masked value stored in source.

NOTE

If file type is word, then mask and source must be words. If file type is long word, mask and source must be long words.

.

•

Mask - The mask operand contains the mask constant, word, or file which is applied to both file and source. When mask bits are set to 1, data is allowed to pass through for comparison. When mask bits are reset to 0, the data is masked (does not pass through to for comparison). The immediate data ranges for mask are from 0 to

0xFFFF or 0 to 0xFFFFFFFF.

NOTE

If mask is direct or indirect, the position selects the location in the specified file.

•

Source - This is the value that is compared to file.

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

EN

(1) --

DN

(2) --

ER

(3) not used

FD

(4) not used

Word 1

Length - contains the number of steps in the sequencer reference file.

Word 2

Position - the current position in the sequence

(1) EN - Enable Bit is set by a false-to-true rung transition and indicates that the instruction is enabled.

(2) DN - Done Bit is set after the instruction has operated on the last word in the sequencer file. It is reset on the next false-to-true rung transition after the rung goes false.

(3) ER - Error Bit is set when the controller detects a negative position value, or a negative or zero length value. When the

ER bit is set, the minor error bit (S2:5/2) is also set.

(4) FD - Found bit is set when the status of all non-masked bits in the source address match those of the word in the sequencer reference file. This bit is assessed each time the SQC instruction is evaluated while the rung is true.

•

Length - The length operand contains the number of steps in the sequencer file (as well as Mask and/or Source if they are file data types). The length of the sequencer can range from 1 to 256.

•

Position - This is the current location or step in the sequencer file (as well as Mask and/or Source if they are file data types). It determines the next location in the stack to receive the current comparison data.

Position is a component of the control register. The position can range from 0 to 255 for words and 0 to 127 for long words. The position is incremented on each false-to-true transition.




Table 15.2 SQC Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

File

Mask

Source

Control

• •

• •

• •

• •

• • •

• • •

(2)

•

•

•

Length

Position


(2) Control file only.

•

•

• •

• • •

• •

•

•

•

• •

• •

• •

•

IMPORTANT



IOS, and DLS files.

SQO- Sequencer Output

Sequencer Output

File #B3:0

Mask

Dest

Control

N7:0

N7:1

R6:0

Length

Position

1<

0<

EN

DN


Table 15.3 Execution Time for the SQO Instruction

Controller

MicroLogix 1200

MicroLogix 1500

Data Size


When Rung Is:

True

23.2

µ s

26.6

µ s

20.0

µ s

23.1

µ s

False

7.1

µ s

7.1

µ s

6.3

µ s

6.3

µ s

On a false-to-true rung transition, the SQO instruction transfers masked source reference words or long words to the destination for the control of sequential machine operations. When the rung goes from false-to-true, the instruction increments to the next step (word) in the sequencer file. Data stored there is transferred through a mask to the destination address specified in the instruction. Data is written to the destination word every time the instruction is executed.

The done bit is set when the last word of the sequencer file is transferred.

On the next false-to-true rung transition, the instruction resets the position to step one.



If the position is equal to zero at start-up, when you switch the controller from the program mode to the run mode, the instruction operation depends on whether the rung is true or false on the first scan.

•

If the rung is true, the instruction transfers the value in step zero.

•

If the rung is false, the instruction waits for the first rung transition from false-to-true and transfers the value in step one.

The bits mask data when reset (0) and pass data when set (1). The instruction will not change the value in the destination word unless you set mask bits.

The mask can be fixed or variable. It is fixed if you enter a hexadecimal code. It is variable if you enter an element address or a file address (direct or indirect) for changing the mask with each step.

The following figure indicates how the SQO instruction works.

Sequencer Output

File

Mask

#B10:1

0F0F

Dest

Control

Length

Position

O14:0

R6:20

4<

2<

EN

DN

Destination O:14.0

15

0000 0101

8 7

0000

Mask Value 0F0F

15

0000 1111

8 7

0000

1010

1111

0

0

Sequencer Output File #B10:1

Word Step

B10:1

0000 0000 0000 0000

0

B10:2

1010 0010 1111 0101

1

B10:3

1111 0101 0100 1010

2

B10:4

0101 0101 0101 0101

3

B10:5

0000 1111 0000 1111

4

Current Step

External Outputs (O:14) at Step 2

00

01

02

03

04

05

10

11

12

13

06

07

08

09

14

15

ON

ON

ON

ON




•

File - This is the sequencer reference file. Its contents, on an element-by-element, basis are masked and stored in the destination.

NOTE


•

Mask - The mask operand contains the mask value. When mask bits are set to 1, data is allowed to pass through to destination. When mask bits are reset to 0, the data is masked (does not pass through to destination). The immediate data ranges for mask are from 0 to

0xFFFF (word) or 0 to 0xFFFFFFFF (long word).

NOTE

If mask is direct or indirect, the position selects the location in the specified file.

•

Destination - The destination operand is the sequencer location or file.

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

EN

(1) --

DN

(2) --

ER

(3) not used FD not used

Word 1

Length - contains the index of the last element in the sequencer reference file

Word 2






•

Length - The length operand contains the number of steps in the sequencer file (as well as Mask and/or Destination if they are file data types). The length of the sequencer can range from 1 to 256.

•

Position - This is the current location or step in the sequencer file (as well as Mask and/or Destination if they are file data types). It determines the next location in the stack to be masked and moved to the destination. Position is a component of the control register. The position can range from 0 to 255. Position is incremented on each false-to-true transition.




Table 15.4 SQO Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

File

(2)

Mask

(2)

Destination

(2)

Control

• •

• •

• •

•

• • •

(3)

•

• • •

•

•

•

Length

Position


(2) File Direct and File Indirect addressing also applies.


• •

•

•

• • •

• •

• •

•

•

• •

• •

• •

IMPORTANT



IOS, and DLS files.

SQL - Sequencer Load

Sequencer Load

File #N7:0

Source

Control

Length

Position

I:0.0

R6:0

1<

0<

EN

DN


Table 15.5 Execution Time for the SQL Instruction

Controller

MicroLogix 1200

MicroLogix 1500

Data Size


When Rung Is:

True

21.7

µ s

24.3

µ s

19.1

µ s

21.1

µ s

False

7.0

µ s

7.1

µ s

6.3

µ s

6.3

µ s



On a false-to-true rung transition, the SQL instruction loads words or long words into a sequencer file at each step of a sequencer operation. This instruction uses the following operands:

•

File - This is the sequencer reference file. Its contents are received on an element-by-element basis from the source.

NOTE


•

Source - The source operand is a constant or address of the value used to fill the currently available position sequencer file. The address level of the source must match the sequencer file. If file is a word type, then source must be a word type. If file is a long word type, then source must be a long word type. The data range for the source is from -32768 to 32767 (word) or -2,147,483,648 to 2,147,483,647

(long word).

•


15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Word 0

EN

(1) --

DN

(2) --

ER

(3) not used FD not used

Word 1

Length - contains the index of the last element in the sequencer reference file

Word 2






•

Length - The length operand contains the number of steps in the sequencer file (this is also the length of source if it is a file data type).

The length of the sequencer can range from 1 to 256.

•

Position - This is the current location or step in the sequencer file (as well as source if it is a file data type). It determines the next location in the stack to receive the value or constant found in source. Position is a component of the control register. The position can range from 0 to 255.




Table 15.6 SQL Instruction Valid Addressing Modes and File Types



Address

Mode

(1)

Parameter

Address

Level

File

(2)

Source

(2)

Control

• •

• •

•

•

(3)

•

•

•

•

Length

Position


(2) File Direct and File Indirect addressing also applies.


• •

•

•

• • •

•

•

•

• •

• •

•

IMPORTANT



IOS, and DLS files.


1

Chapter

16

Program Control Instructions

Use these instructions to change the order in which the processor scans a ladder program. Typically these instructions are used to minimize scan time, create a more efficient program, and troubleshoot a ladder program.

Instruction

JMP - Jump to Label

LBL - Label

JSR - Jump to Subroutine

SBR - Subroutine Label

RET - Return from Subroutine

SUS - Suspend

TND - Temporary End

END - Program End

MCR - Master Control Reset

Used To:

Jump forward/backward to a corresponding label instruction

Page

16-1

16-2

Jump to a designated subroutine and return

16-2

16-3

16-3

Debug or diagnose your user program

Abort current ladder scan

End a program or subroutine

Enable or inhibit a master control zone in your ladder program

16-4

16-4

16-5

16-5

JMP - Jump to Label

Q2:0

JMP


Table 16.1 Execution Time for the JMP Instruction


True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 1.0

µ s

False

0.0

µ s

0.0

µ s

The JMP instruction causes the controller to change the order of ladder execution. Jumps cause program execution to go to the rung marked LBL

label number. Jumps can be forward or backward in ladder logic within the same program file. Multiple JMP instructions may cause execution to proceed to the same label.

The immediate data range for the label is from 0 to 999. The label is local to a program file.


16-2 Program Control Instructions

LBL - Label

Q2:0

LBL


Table 16.2 Execution Time for the LBL Instruction


True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 1.0

µ s

False

1.0

µ s

1.0

µ s

The LBL instruction is used in conjunction with a jump (JMP) instruction to change the order of ladder execution. Jumps cause program execution to go to the rung marked LBL label number.

The immediate data range for the label is from 0 to 999. The label is local to a program file.

JSR - Jump to

Subroutine

Jump To Subroutine

SBR File Number U:255


Table 16.3 Execution Time for the JSR Instruction


True

MicroLogix 1200 8.4

µ s

MicroLogix 1500 8.0

µ s

False

0.0

0.0

µ

µ s s

The JSR instruction causes the controller to start executing a separate subroutine file within a ladder program. JSR moves program execution to the designated subroutine (SBR file number). After executing the SBR, control proceeds to the instruction following the JSR instruction.

The immediate data range for the JSR file is from 3 to 255.


Program Control Instructions 16-3

SBR - Subroutine Label

Subroutine


Table 16.4 Execution Time for the SBR Instruction


True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 1.0

µ s

False

1.0

µ s

1.0

µ s

The SBR instruction is a label which is not used by the processor. It is for user subroutine identification purposes as the first rung for that subroutine. This instruction is the first instruction on a rung and is always evaluated as true.

RET - Return from

Subroutine

Return


Table 16.5 Execution Time for the RET Instruction


True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 1.0

µ s

False

0.0

µ s

0.0

µ s

The RET instruction marks the end of subroutine execution or the end of the subroutine file. It causes the controller to resume execution at the instruction following the JSR instruction, user interrupt, or user fault routine that caused this subroutine to execute.



SUS - Suspend

Suspend

Suspend ID 1


The SUS instruction is used to trap and identify specific conditions for program debugging and system troubleshooting. This instruction causes the processor to enter the suspend idle mode, causing all outputs to be de-energized. The suspend ID and the suspend file (program file number or subroutine file number identifying where the suspend instruction resides) are placed in the status file (S:7 and S:8).

The immediate data range for the suspend ID is from -32768 to 32767.

TND - Temporary End

TND


Table 16.6 Execution Time for the TND Instruction


True

MicroLogix 1200 0.9

µ s

MicroLogix 1500 1.0

µ s

False

0.0

0.0

µ

µ s s

The TND instruction is used to denote a premature end-of-ladder program execution. The TND instruction cannot be executed from a STI subroutine, HSC subroutine, EII subroutine, or a user fault subroutine.

This instruction may appear more than once in a ladder program.

On a true rung, TND stops the processor from scanning the rest of the program file. In addition, this instruction performs the output scan, input scan, and housekeeping aspects of the processor scan cycle prior to resuming scanning at rung 0 of the main program (file 2). If this instruction is executed in a nested subroutine, it terminates execution of all nested subroutines.


Program Control Instructions 16-5

END - Program End

END


The END instruction must appear at the end of every ladder program. For the main program file (file 2), this instruction ends the program scan. For a subroutine, interrupt, or user fault file, the END instruction causes a return from subroutine.

MCR - Master Control

Reset

MCR


Table 16.7 Execution Time for the MCR Instructions

Controller Instruction

MicroLogix 1200 MCR Start

MicroLogix 1500

MCR End

MCR Start

MCR End

When Rung Is:

True

1.2

µ s

1.6

µ s

0.8

µ s

1.0

µ s

False

1.2

µ s

1.6

µ s

0.8

µ s

1.0

µ s

The MCR instruction works in pairs to control the ladder logic found between those pairs. Rungs within the MCR zone are still scanned, but scan time is reduced due to the false state of non-retentive outputs.

Non-retentive outputs are reset when the rung goes false.

This instruction defines the boundaries of an MCR Zone. An MCR Zone is the set of ladder logic instructions bounded by an MCR instruction pair.

The start of an MCR zone is defined to be the rung that contains an MCR instruction preceded by conditional logic. The end of an MCR zone is defined to be the first rung containing just an MCR instruction following a start MCR zone rung as shown below.

0030

I:1

0

MCR

0031

Ladder Logic within MCR Zone

0032

0033

MCR



While the rung state of the first MCR instruction is true, execution proceeds as if the zone were not present. When the rung state of the first

MCR instruction is false, the ladder logic within the MCR zone is executed as if the rung is false. All non-retentive outputs within the MCR zone are reset.

MCR zones let you enable or inhibit segments of your program, such as for recipe applications.

When you program MCR instructions, note that:

•

You must end the zone with an unconditional MCR instruction.

•

You cannot nest one MCR zone within another.

•

Do not jump into an MCR zone. If the zone is false, jumping into it activates the zone.

NOTE

The MCR instruction is not a substitute for a hard-wired master control relay that provides emergency stop capability. You still must install a hard-wired master control relay to provide emergency I/O power shutdown.

ATTENTION

!

If you start instructions such as timers or counters in an

MCR zone, instruction operation ceases when the zone is disabled. Re-program critical operations outside the zone if necessary.


1

Chapter

17

Input and Output Instructions

The input and output instructions allow you to selectively update data without waiting for the input and output scans.

Instruction Used To:

IIM - Immediate Input with Mask Update data prior to the normal input scan.

Page

17-1

Update outputs prior to the normal output scan. 17-3

IOM - Immediate Output with

Mask

REF - I/O Refresh

17-4

Interrupt the program scan to execute the

I/O scan (write outputs, service communications, read inputs)

IIM - Immediate Input with Mask

Immediate Input w/Mask

Slot I:0.0

Mask

Length

N7:0

1


NOTE

This instruction is used for embedded I/O only. It is not designed to be used with expansion I/O.

Table 17.1 Execution Time for the IIM Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

26.4

µ s

22.5

µ s

False

0.0

µ s

0.0

µ s


17-2 Input and Output Instructions

The IIM instruction allows you to selectively update input data without waiting for the automatic input scan. This instruction uses the following operands:

•

Slot - This operand defines the location where data is obtained for updating the input file. The location specifies the slot number and the word where data is to be obtained. For example, if slot = I:0, input data from slot 0 starting at word 0 is masked and placed in input data file I:0 starting at word 0 for the specified length. If slot = I0.1, word 1 of slot 0 is used, and so on.

IMPORTANT

Slot 0 is the only valid slot number that can be used with this instruction. IIM cannot be used with expansion I/O.

•

Mask - The mask is a hex constant or register address containing the mask value to be applied to the slot. If a given bit position in the mask is a “1”, the corresponding bit data from slot is passed to the input data file. A “0” prohibits corresponding bit data in slot from being passed to the input data file. The mask value can range from 0 to 0xFFFF.

Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Real Input Input Word

Mask

Input Data

File

0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1

Data is Not Updated Updated to Match Input Word

•

Length - This is the number of masked words to transfer to the input data file.

Addressing Modes and File Types can be used as shown below:

Table 17.2 IIM Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Slot

Mask

Length

•

• • • • •

•

• • •

•

•

•


Input and Output Instructions 17-3

IOM - Immediate Output with Mask

Immediate Output w/Mask

Slot

Mask

Length

O:0.0

N7:0

1


NOTE

This instruction is used for embedded I/O only. It is not designed to be used with expansion I/O.

Table 17.3 Execution Time for the IOM Instruction


MicroLogix 1200

True

22.3

µ s

MicroLogix 1500 1764-LSP 18.4

µ s

MicroLogix 1500 1764-LRP 19.4

µ s

False

0.0

0.0

0.0

µ

µ

µ s s s

The IOM instruction allows you to selectively update output data without waiting for the automatic output scan. This instruction uses the following operands:

•

Slot - The slot is the physical location that is updated with data from the output file.

IMPORTANT

Slot 0 is the only valid slot number that can be used with this instruction. IOM cannot be used with expansion I/O.

•

Mask - The mask is a hex constant or register address containing the mask value to be applied. If a given bit position in the mask is a “1”, the corresponding bit data is passed to the physical outputs. A “0” prohibits corresponding bit data from being passed to the outputs.

The mask value can range from 0 to 0xFFFF.

Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Output Data Output Word

Mask 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1

Real Outputs Data is Not Updated Updated to Match Output Word

•

Length - This is the number of masked words to transfer to the outputs.


17-4 Input and Output Instructions

REF- I/O Refresh

REF


Table 17.4 IOM Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Slot

Mask

Length

•

• • • • •

•

• • •

•

•

•


Table 17.5 Execution Time for the REF Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

see p. A-7

see p. B-6

False

0.0

µ s

0.0

µ s

The REF instruction is used to interrupt the program scan to execute the

I/O scan and service communication portions of the operating cycle for all communication channels. This includes: write outputs, service communications (all communication channels, communications toggle push-button, DAT [MicroLogix 1500 only], and comms housekeeping), and read inputs.

The REF instruction has no programming parameters. When it is evaluated as true, the program scan is interrupted to execute the I/O scan and service communication portions of the operating cycle. The scan then resumes at the instruction following the REF instruction.

The REF instruction cannot be executed from an STI subroutine, HSC subroutine, EII subroutine, or a user fault subroutine.

NOTE

Using an REF instruction may result in input data changing in the middle of a program scan. This condition needs to be evaluated when using the REF instruction.

ATTENTION

!

The watchdog and scan timers are reset when executing the REF instruction. You must insure that the REF instruction is not placed inside a non-terminating program loop. Do not place the REF instruction inside a program loop unless the program is thoroughly analyzed.


Chapter

18

Using Interrupts

Interrupts allow you to interrupt your program based on defined events.

This chapter contains information about using interrupts, the interrupt instructions, and the interrupt function files. The chapter is arranged as follows:

•

Information About Using Interrupts on page 18-2.

•

User Interrupt Instructions on page 18-7.

•

Using the Selectable Timed Interrupt (STI) Function File on page 18-12.

•

Using the Event Input Interrupt (EII) Function File on page 18-17.

See also: Using the High-Speed Counter on page5-1.


18-2 Using Interrupts

Information About Using

Interrupts

The purpose of this section is to explain some fundamental properties of the User Interrupts, including:

•

What is an interrupt?

•

When can the controller operation be interrupted?

•

Priority of User Interrupts

•

Interrupt Latency

•

User Fault Routine

What is an Interrupt?

An interrupt is an event that causes the controller to suspend the task it is currently performing, perform a different task, and then return to the suspended task at the point where it suspended. The Micrologix 1200 and

MicroLogix 1500 support the following User Interrupts:

•

User Fault Routine

•

Event Interrupts (4)

•

High-Speed Counter Interrupts

(1)

•


An interrupt must be configured and enabled to execute. When any one of the interrupts is configured (and enabled) and subsequently occurs, the user program:

1. suspends its execution

2. performs a defined task based upon which interrupt occurred

3. returns to the suspended operation.

Interrupt Operation Example

rung 0

Program File 2

Program File 10

Program File 2 is the main control program.

Program File 10 is the interrupt routine.

•

An Interrupt Event occurs at rung 123.

•

Program File 10 is executed.

•

Program File 2 execution resumes immediately after program file 10 is scanned.

rung 123 rung 275


(1) The MicroLogix 1200 has one HSC Interrupt, HSC0. The MicroLogix 1500 has two, HSC0 and HSC1.

Using Interrupts 18-3

Specifically, if the controller program is executing normally and an interrupt event occurs:

1. the controller stops its normal execution

2. determines which interrupt occurred

3. goes immediately to rung 0 of the subroutine specified for that User

Interrupt

4. begins executing the User Interrupt subroutine (or set of subroutines if the specified subroutine calls a subsequent subroutine)

5. completes the subroutine(s)

6. resumes normal execution from the point where the controller program was interrupted

When Can the Controller Operation be Interrupted?

The Micrologix 1200 and 1500 controllers only allow interrupts to be serviced during certain periods of a program scan. They are:

•

At the start of a ladder rung

•

Anytime during End of Scan

•

Between data words in an expansion I/O scan

The interrupt is only serviced by the controller at these opportunities. If the interrupt is disabled, the pending bit is set at the next occurrence of one of the three occasions listed above.

ATTENTION

!


OTL, OTE, or UIE, this instruction (OTL, OTE, or UIE)

must be the last instruction executed on the rung (last instruction on last branch). It is recommended this be the only output instruction on the rung.



Priority of User Interrupts

When multiple interrupts occur, the interrupts are serviced based upon their individual priority.

When an interrupt occurs and another interrupt(s) has already occurred but has not been serviced, the new interrupt is scheduled for execution based on its priority relative to the other pending interrupts. At the next point in time when an interrupt can be serviced, all the interrupts are executed in the sequence of highest priority to lowest priority.

If an interrupt occurs while a lower priority interrupt is being serviced

(executed), the currently executing interrupt routine is suspended, and the higher priority interrupt is serviced. Then the lower priority interrupt is allowed to complete before returning to normal processing.

If an interrupt occurs while a higher priority interrupt is being serviced

(executed), and the pending bit has been set for the lower priority interrupt, the currently executing interrupt routine continues to completion. Then the lower priority interrupt runs before returning to normal processing.

The priorities from highest to lowest are:

highest priority

User Fault Routine

Event Interrupt 0

Event Interrupt 1

High-Speed Counter Interrupt 0

Event Interrupt 2

Event Interrupt 3

High-Speed Counter Interrupt 1

(MicroLogix 1500 only.)


lowest priority



Interrupt Latency

Interrupt Latency is defined as the worst case amount of time elapsed from when an interrupt occurs to when the interrupt subroutine starts to execute. The tables below show the interaction between an interrupt and the controller operating cycle.

Program Scan Activity When an Interrupt Can Occur

Input Scan

Ladder Scan

Output Scan

Communications Service

Between word updates

Start of Rung

Between word updates

Anytime

(1)(2)

Housekeeping Anytime

(1) Communications Services includes 80

µ s to get into a subroutine

(2) Communication Service includes 60

µ s for a time tick.

To determine the interrupt latency:

1. First determine the execution time for the longest executing rung in

your control program (maximum rung time). See MicroLogix 1500

Memory Usage and Instruction Execution Time on page B-1 or

MicroLogix 1500 Memory Usage and Instruction Execution Time on page B-1 for more information.

2. Multiply the maximum rung time by the Communications Multiplier

corresponding to your configuration in the MicroLogix 1200 Scan

Time Worksheet on page A-7, or MicroLogix 1500 Scan Time

Worksheet on page B-6.

Evaluate your results as follows:

Controller If the time calculated in step 2 is: Then the Interrupt Latency is:

MicroLogix 1200 less than 133 µs 411 µs greater than 133 µs

MicroLogix 1500 less than 100 µs greater than 100 µs the value calculated in step 2 plus 278 µs

360 µs the value calculated in step 2 plus 260 µs



User Fault Routine

The user fault routine gives you the option of preventing a controller shutdown when a specific user fault occurs. The fault routine is executed when any recoverable or non-recoverable user fault occurs. The fault routine is not executed for non-user faults.

Faults are classified as recoverable, non-recoverable, and non-user faults.

A complete list of faults is shown in Fault Messages and Error Codes on page D-1. The basic types of faults are described below:

Recoverable Non-Recoverable Non-User Fault

Recoverable Faults are caused by the user and may be recovered from by executing logic in the user fault routine. The user can attempt to clear the Major Error

Halted bit, S:1/13.

Note: You may initiate a MSG instruction from the controller to another device to identify the fault condition of the controller.

Non-Recoverable Faults are caused by the user, and cannot be recovered from. The user fault routine executes when this type of fault occurs.

However, the fault cannot be cleared.

Note: You may initiate a MSG instruction to another device to identify the fault condition of the controller.

Non-User Faults are caused by various conditions that cease ladder program execution. The user fault routine does not execute when this type of fault occurs.

Status File Data Saved

The Arithmetic Flags (Status File word S:0) are saved on entry to the user fault subroutine and re-written upon exiting the subroutine.

Creating a User Fault Subroutine

To use the user fault subroutine:

1. Create a subroutine file. Program Files 3 to 255 can be used.

2. Enter the file number in word S:29 of the status file.

Controller Operation

The occurrence of recoverable or non-recoverable faults causes the controller to read S:29 and execute the subroutine number identified by

S:29. If the fault is recoverable, the routine can be used to correct the problem and clear the fault bit S:1/13. The controller then continues in its current executing mode. The routine does not execute for non-user faults.


User Interrupt

Instructions



INT - Interrupt Subroutine Use this instruction to identify a program file as an interrupt subroutine (INT label) versus a regular subroutine (SBR label). This should be the first instruction in your interrupt subroutine.

STS - Selectable Timed

Start

Use the STS (Selectable Timed Interrupt Start) instruction to the start the STI timer from the control program, rather than starting automatically.

UID - User Interrupt Disable Use the User Interrupt Disable (UID) and the User


Interrupt Enable (UIE) instructions to create zones in which I/O interrupts cannot occur.

UIF - User Interrupt Flush Use the UIF instruction to remove selected pending interrupts from the system.

Page

18-7

18-8

18-9

18-10

18-11

INT - Interrupt

Subroutine

I/O Interrupt


Table 18.1 Execution Time for the INT Instruction


True

MicroLogix 1200 1.0

µ s

MicroLogix 1500 1.0

µ s

False

1.0

µ s

1.0

µ s

The INT instruction is used as a label to identify a user interrupt service routine (ISR). This instruction is placed as the first instruction on a rung and is always evaluated as true. Use of the INT instruction is optional.



STS - Selectable Timed

Start

Selectable Timed Start

Time 1


Table 18.2 Execution Time for the STS Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

57.5

µ s

50.7

µ s

False

0.0

µ s

0.0

µ s

The STS instruction can be used to start and stop the STI function or to change the time interval between STI user interrupts. The STI instruction has one operand:

•

Time - This is the amount of time (in milliseconds) which must expire prior to executing the selectable timed user interrupt. A value of zero disables the STI function. The time range is from 0 to 65,535 milliseconds.

The STS instruction applies the specified set point to the STI function as follows:

•

If a zero set point is specified, the STI is disabled and STI:0/TIE is cleared (0).

•

If the STI is disabled (not timing) and a value greater than 0 is entered into the set point, the STI starts timing to the new set point and STI:0/

TIE is set (1).

•

If the STI is currently timing and the set point is changed, the new setting takes effect immediately and the STI continues to time until it reaches the new set point.

Note that if the new setting is less than the current accumulated time, the STI times-out immediately. For example, if the STI has been timing for 15 microseconds, and the STI set point is changed from 20 microseconds to 10 microseconds, an STI user interrupt occurs at the next start-of-rung.


Table 18.3 STS Instruction Valid Addressing Modes and File Types



Address

(1)

Mode

Parameter

Address

Level

Time • • • • •


• • • •

IMPORTANT



IOS, and DLS files.



UID - User Interrupt

Disable

User Interrupt Disable

Interrupt Types 5


Table 18.4 Execution Time for the UID Instruction


True

MicroLogix 1200 0.8

µ s

MicroLogix 1500 0.8

µ s

False

0.0

0.0

µ

µ s s

The UID instruction is used to disable selected user interrupts. The table below shows the types of interrupts with their corresponding disable bits:

Table 18.5 Types of Interrupts Disabled by the UID Instruction

Interrupt

EII - Event Input Interrupts


HSC - High-Speed Counter




(1)

STI - Selectable Timed Interrupts

Element

Event 0

Event 1

HSC0

Event 2

Event 3

HSC1

Decimal

Value

64

32

16

8

4

2

STI 1 bit 0

Note: Bits 7 to 15 must be set to zero.


Corresponding

Bit

bit 6 bit 5 bit 4 bit 3 bit 2 bit 1

To disable interrupt(s):

1. Select which interrupts you want to disable.

2. Find the Decimal Value for the interrupt(s) you selected.

3. Add the Decimal Values if you selected more than one type of interrupt.

4. Enter the sum into the UID instruction.

For example, to disable EII Event 1 and EII Event 3:

EII Event 1 = 32, EII Event 3 = 4

32 + 4 = 36 (enter this value)



UIE - User Interrupt

Enable

User Interrupt Enable

Interrupt Types 4


Table 18.6 Execution Time for the UIE Instruction


True

MicroLogix 1200 0.8

µ s

MicroLogix 1500 0.8

µ s

False

0.0

µ s

0.0

µ s

The UIE instruction is used to enable selected user interrupts. The table below shows the types of interrupts with their corresponding enable bits:

Table 18.7 Types of Interrupts Disabled by the UIE Instruction

Interrupt







(1)


Element

Event 0

Event 1

HSC0

Event 2

Event 3

HSC1

Decimal

Value

64

32

16

8

4

2

Corresponding

Bit


STI 1 bit 0



To enable interrupt(s):

1. Select which interrupts you want to enable.



4. Enter the sum into the UIE instruction.

For example, to enable EII Event 1 and EII Event 3:



ATTENTION

!





UIF - User Interrupt

Flush

User Interrupt Flush

Interrupt Types 1


Table 18.8 Execution Time for the UIF Instruction

Controller

MicroLogix 1200

MicroLogix 1500

When Rung Is:

True

12.3

µ s

10.6

µ s

False

0.0

µ s

0.0

µ s

The UIF instruction is used to flush (remove pending interrupts from the system) selected user interrupts. The table below shows the types of interrupts with their corresponding flush bits:

Table 18.9 Types of Interrupts Disabled by the UIF Instruction

Interrupt







(1)

Element

Event 0

Event 1

HSC0

Event 2

Event 3

HSC1

Decimal

Value

64

32

16

8

4

2



STI 1 bit 0


Corresponding

Bit


To flush interrupt(s):

1. Select which interrupts you want to flush.



4. Enter the sum into the UIF instruction.

For example, to disable EII Event 1 and EII Event 3:





Using the Selectable

Timed Interrupt (STI)

Function File

The Selectable Timed Interrupt (STI) provides a mechanism to solve time critical control requirements. The STI is a trigger mechanism that allows you to scan or solve control program logic that is time sensitive.

Example of where you would use the STI are:

•

PID type applications, where a calculation must be performed at a specific time interval.

•

A motion application, where the motion instruction (PTO) needs to be scanned at a specific rate to guarantee a consistent acceleration/ deceleration profile.

•

A block of logic that needs to be scanned more often.

How an STI is used is typically driven by the demands/requirements of the application. It operates using the following sequence:

1. The user selects a time interval.

2. When a valid interval is set and the STI is properly configured, the controller monitors the STI value.

3. When the time period has elapsed, the controller’s normal operation is interrupted.

4. The controller then scans the logic in the STI program file.

5. When the STI file scan is completed, the controller returns to where it was prior to the interrupt and continues normal operation.



Selectable Time Interrupt (STI) Function File Sub-Elements Summary

Table 18.10 Selectable Timed Interrupt Function File (STI:0)

Sub-Element Description Address Data Format Type


ER - Error Code

UIX - User Interrupt Executing




TIE - Timed Interrupt Enabled

AS - Auto Start

ED - Error Detected

SPM - Set Point Msec

STI:0.PFN

STI:0.ER

STI:0/UIX

STI:0/UIE

STI:0/UIL

STI:0/UIP

STI:0/TIE

STI:0/AS

STI:0/ED

STI:0.SPM

word (INT) word (INT) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) word (INT) control status status control status status control control status control

User Program

Access

read only read only read only read/write read/write read only read/write read only read only read/write

18-15

18-15

18-15

18-16

18-16

For More

Information

18-13

18-13

18-14

18-14

18-14

STI Function File Sub-Elements

STI Program File Number (PFN)



Address

STI:0.PFN


word (INT)

User Program

Access

control read only

The PFN (Program File Number) variable defines which subroutine is called (executed) when the timed interrupt times out. A valid subroutine file is any program file (3 to 255).

The subroutine file identified in the PFN variable is not a special file within the controller; it is programmed and operates the same as any other program file. From the control program perspective it is unique, in that it is automatically scanned based on the STI set point.

STI Error Code (ER)


ER - Error Code

Address

STI:0.ER


word (INT) status

User Program

Access

read only

Error codes detected by the STI sub-system are displayed in this register.

The table below explains the error codes.

Table 18.11 STI Error Code

Error

Code

1

Recoverable Fault

(Controller)

Invalid Program File

Number

Description

Program file number is less than 3, greater than 255, or does not exist.



STI User Interrupt Executing (UIX)


UIX - User Interrupt Executing STI:0/UIX binary (bit) status

User Program

Access

read only

The UIX (User Interrupt Executing) bit is set whenever the STI mechanism completes timing and the controller is scanning the STI PFN. The UIX bit is cleared when the controller completes processing the STI subroutine.

The STI UIX bit can be used in the control program as conditional logic to detect if an STI interrupt is executing.

STI User Interrupt Enable (UIE)

Sub-Element Description Address

UIE - User Interrupt Enable STI:0/UIE


binary (bit)

User Program

Access

control read/write

The UIE (User Interrupt Enable) bit is used to enable or disable STI subroutine processing. This bit must be set if you want the controller to process the STI subroutine at the configured time interval.

If you need to restrict when the STI subroutine is processed, clear the UIE bit. An example of when this is important is if a series of math calculations need to be processed without interruption. Before the calculations take place, clear the UIE bit. After the calculations are complete, set the UIE bit and STI subroutine processing resumes.

STI User Interrupt Lost (UIL)


UIL - User Interrupt Lost STI:0/UIL


binary (bit) status

User Program

Access

read/write

The UIL (User Interrupt Lost) is a status flag that indicates an interrupt was lost. The controller can process 1 active and maintain up to 2 pending user interrupt conditions before it sets the lost bit.

This bit is set by the controller. It is up to the control program to utilize, track if necessary, and clear the lost condition.



STI User Interrupt Pending (UIP)


UIP - User Interrupt Pending STI:0/UIP


binary (bit) status

User Program

Access

read only

The UIP (User Interrupt Pending) is a status flag that represents an interrupt is pending. This status bit can be monitored or used for logic purposes in the control program if you need to determine when a subroutine cannot execute immediately.

This bit is automatically set and cleared by the controller. The controller can process 1 active and maintain up to 2 pending user interrupt conditions before it sets the lost bit.

STI Timed Interrupt Enabled (TIE)


TIE - Timed Interrupt Enabled STI:0/TIE


binary (bit)

User Program

Access

control read/write

The TIE (Timed Interrupt Enabled) control bit is used to enable or disable the timed interrupt mechanism. When set (1), timing is enabled, when clear (0) timing is disabled. If this bit is cleared (disabled) while the timer is running, the accumulated value is cleared (0). If the bit is then set (1), timing starts.

This bit is controlled by the user program and retains its value through a power cycle.

STI Auto Start (AS)


AS - Auto Start STI:0/AS


binary (bit)

User Program

Access

control read only

The AS (Auto Start) is a control bit that can be used in the control program. The auto start bit is configured with the programming device and stored as part of the user program. The auto start bit automatically sets the STI Timed Interrupt Enable (TIE) bit when the controller enters any executing mode.



STI Error Detected (ED)


ED - Error Detected

Address

STI:0/ED


binary (bit) status

User Program

Access

read only

The ED (Error Detected) flag is a status bit that can be used by the control program to detect if an error is present in the STI sub-system. The most common type of error that this bit represents is a configuration error.

When this bit is set, the user should look at the error code in parameter

STI:0.ER

This bit is automatically set and cleared by the controller.

STI Set Point Milliseconds Between Interrupts (SPM)

Sub-Element

Description

SPM - Set Point

Msec

Address

STI:0.SPM

Data Format

word (INT)

Range

0 to

65,535


Access

control read/write

When the controller transitions to an executing mode, the SPM (set point in milliseconds) value is loaded into the STI. If the STI is configured correctly, and enabled, the program file identified in the STI variable PFN is scanned at this interval. This value can be changed from the control program by using the STS instruction.

NOTE

The minimum value cannot be less than the time required to scan the STI program file (STI:0.PFN) plus the Interrupt

Latency.



Using the Event Input

Interrupt (EII) Function

File

The EII (event input interrupt) is a feature that allows the user to scan a specific program file (subroutine) when an input condition is detected from a field device.

Within the function file section of RSLogix 500, the user sees an EII folder.

Within the folder are four EII elements. Each of these elements (EII:0,

EII:1, EII:2, and EII:3) are identical; this explanation uses EII:0 as shown below.

Each EII can be configured to monitor any one of the first eight inputs

(I1:0.0/0 to I1:0.0/7). Each EII can be configured to detect rising edge or falling edge input signals. When the configured input signal is detected at the input terminal, the controller immediately scans the configured subroutine.

Event Input Interrupt (EII) Function File Sub-Elements Summary

Table 18.12 Event Input Interrupt Function File (EII:0)



ER - Error Code

UIX - User Interrupt Executing




EIE - Event Interrupt Enabled

AS - Auto Start

ED - Error Detected

ES - Edge Select

IS - Input Select

EII:0.PFN

EII:0.ER

EII:0/UIX

EII:0/UIE

EII:0/UIL

EII:0/UIP

EII:0/EIE

EII:0/AS

EII:0/ED

EII:0/ES

EII:0.IS

word (INT) word (INT) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) word (INT) control status status control status status control control status control control

User Program

Access

read only read only read only read/write read/write read only read/write read only read only read only read only

18-20

18-20

18-20

18-21

18-21

For More

Information

18-18

18-18

18-18

18-19

18-19

18-19




EII Function File Sub-Elements

EII Program File Number (PFN)


PFN - Program File Number EII:0.PFN

Data Format

word (INT)


Access

control read only

PFN (Program File Number) defines which subroutine is called (executed) when the input terminal assigned to EII:0 detects a signal. A valid subroutine file is any program file (3 to 255).

The subroutine file identified in the PFN variable is not a special file within the controller. It is programmed and operated the same as any other program file. From the control program perspective it is unique, in that it is automatically scanned based on the configuration of the EII.

EII Error Code (ER)


ER - Error Code EII:0.ER

Data Format

word (INT)

Type

status

User Program

Access

read only

Any ER (Error Code) detected by the EII sub-system is displayed in this register. The table below explains the error codes.

Table 18.13 EII Error Codes

Error

Code

1

2

3

Recoverable Fault

(Controller)

Invalid Program File

Number

Invalid Input

Selection

Input Selection

Overlap

Description

Program file number is less than 3, greater than 255, or does not exist

Valid numbers must be 0, 1, 2, 3, 4, 5, 6, or 7.

EIIs cannot share inputs. Each EII must have a unique input.

EII User Interrupt Executing (UIX)


UIX - User Interrupt Executing EII:0/UIX

Data Format

binary (bit)

Type

status

User Program

Access

read only

The UIX (User Interrupt Executing) bit is set whenever the EII mechanism detects a valid input and the controller is scanning the PFN. The EII mechanism clears the UIX bit when the controller completes its processing of the EII subroutine.

The EII UIX bit can be used in the control program as conditional logic to detect if an EII interrupt is executing.


EII User Interrupt Enable (UIE)


UIE - User Interrupt Enable EII:0/UIE

Data Format

binary (bit)


Access

control read/write

The UIE (User Interrupt Enable) bit is used to enable or disable EII subroutine processing. This bit must be set if you want the controller to process the EII subroutine when an EII event occurs.

If you need to restrict when the EII subroutine is processed, clear the UIE bit. An example of when this is important is if a series of math calculations need to be processed without interruption. Before the calculations take place, clear the UIE bit. After the calculations are complete, set the UIE bit and EII subroutine processing resumes.

EII User Interrupt Lost (UIL)


UIL - User Interrupt Lost EII:0/UIL

Data Format

binary (bit)

Type

status

User Program

Access

read/write

UIL (User Interrupt Lost) is a status flag that represents an interrupt has been lost. The controller can process 1 active and maintain up to 2 pending user interrupt conditions before it sets the lost bit.

This bit is set by the controller. It is up to the control program to utilize, track, and clear the lost condition.

EII User Interrupt Pending (UIP)


UIP - User Interrupt Pending EII:0/UIP

Data Format

binary (bit)

Type

status

User Program

Access

read only

UIP (User Interrupt Pending) is a status flag that represents an interrupt is pending. This status bit can be monitored, or used for logic purposes, in the control program if you need to determine when a subroutine cannot execute immediately.

This bit is automatically set and cleared by the controller. The controller can process 1 active and maintain up to 2 pending user interrupt conditions before it sets the pending bit.



EII Event Interrupt Enable (EIE)


EIE - Event Interrupt Enabled EII:0/EIE

Data Format

binary (bit)


Access

control read/write

EIE (Event Interrupt Enabled) allows the event interrupt function to be enabled or disabled from the control program. When set (1), the function is enabled, when cleared (0, default) the function is disabled.

This bit is controlled by the user program and retains its value through a power cycle.

EII Auto Start (AS)


AS - Auto Start EII:0/AS

Data Format

binary (bit)


Access

control read only

AS (Auto Start) is a control bit that can be used in the control program.

The auto start bit is configured with the programming device and stored as part of the user program. The auto start bit automatically sets the EII

Event Interrupt Enable (EIE) bit when the controller enters any executing mode.

EII Error Detected (ED)


ED - Error Detected EII:0/ED

Data Format

binary (bit)

Type

status

User Program

Access

read only

The ED (Error Detected) flag is a status bit that can be used by the control program to detect if an error is present in the EII sub-system. The most common type of error that this bit represents is a configuration error.

When this bit is set, look at the specific error code in parameter EII:0.ER

This bit is automatically set and cleared by the controller.



EII Edge Select (ES)


ES - Edge Select EII:0/ES

Data Format

binary (bit)


Access

control read only

The ES (Edge Select) bit selects the type of trigger that causes an Event

Interrupt. This bit allows the EII to be configured for rising edge

(off-to-on, 0-to-1) or falling edge (on-to-off, 1-to-0) signal detection. This selection is based on the type of field device that is connected to the controller.

The default condition is 1, which configures the EII for rising edge operation.

EII Input Select (IS)


IS - Input Select EII:0.IS

Data Format

word (INT)


Access

control read only

The IS (Input Select) parameter is used to configure each EII to a specific input on the controller. Valid inputs are 0 to 7, which correspond to

I1:0.0/0 to I1:0.0/7.

This parameter is configured with the programming device and cannot be changed from the control program.




1

The PID Concept

Chapter

19

Process Control Instruction

This chapter describes the MicroLogix 1200 and MicroLogix 1500

Proportional Integral Derivative (PID) instruction. The PID instruction is an output instruction that controls physical properties such as temperature, pressure, liquid level, or flow rate using process loops.

The PID instruction normally controls a closed loop using inputs from an analog input module and providing an output to an analog output module. For temperature control, you can convert the analog output to a time proportioning on/off output for driving a heater or cooling unit. An

example appears on page 19-17.

The PID instruction can be operated in the timed mode or the Selectable

Time Interrupt (STI mode). In the timed mode, the instruction updates its output periodically at a user-selectable rate. In the STI mode, the instruction should be placed in an STI interrupt subroutine. It then updates its output every time the STI subroutine is scanned. The STI time interval and the PID loop update rate must be the same in order for the

equation to execute properly. See Using the Selectable Timed Interrupt

(STI) Function File on page 18-12 for more information on STI interrupts.

PID closed loop control holds a process variable at a desired set point. A flow rate/fluid level example is shown below.

Feed Forward Bias

Set Point

Flow Rate

∑

Error

Process

Variable

PID

Equation

∑

Control

Output

Level

Detector

Control Valve

The PID equation controls the process by sending an output signal to the control valve. The greater the error between the setpoint and process variable input, the greater the output signal. Alternately, the smaller the error, the smaller the output signal. An additional value (feed forward or bias) can be added to the control output as an offset. The PID result

(control variable) drives the process variable toward the set point.


19-2 Process Control Instruction

The PID Equation

The PID instruction uses the following algorithm:

Standard equation with dependent gains:

Output

=

K

C

+

1

T

I

∫

( )

d t

+

T

D

⋅

d PV dt

)

+

bias

Standard Gains constants are:

Term Range (Low to High)

Controller Gain K

C

0.01 to 327.67 (dimensionless)

(1)

Reference

Proportional

Reset Term 1/T

Rate Term T

D

I

327.67 to 0.01 (minutes per repeat)

(1)

0.01 to 327.67 (minutes)

(1)

Integral

Derivative

(1) Applies to MicroLogix 1200 and 1500 PID range when Reset and Gain Range (RG) bit is set to 1. For more information

on reset and gain, see PLC 5 Gain Range (RG) on pa ge19-13.

The derivative term (rate) provides smoothing by means of a low-pass filter. The cut-off frequency of the filter is 16 times greater than the corner frequency of the derivative term.

PD Data File

The PID instruction implemented by the MicroLogix 1200 and 1500 controllers is virtually identical in function to the PID implementation used by the Allen-Bradley SLC 5/03 and higher processors. Minor differences primarily involve enhancements to terminology. The major difference is that the PID instruction now has its own data file. In the SLC family of processors, the PID instruction operated as a block of registers within an integer file. The Micrologix 1200 and 1500 PID instruction utilizes a PD data file.

You can create a PD data file by creating a new data file and classifying it as a PD file type. RSLogix automatically creates a new PD file or a PD sub-element whenever a PID instruction is programmed on a rung. The

PD file then appears in the list of Data Files as shown in the illustration.

Each PD data file has a maximum of 255 elements and each PID instruction requires a unique PD element. Each PD element is composed of 20 sub-elements, which include bit, integer and long integer data. All of the examples in this chapter use PD file 10 sub-element 0.

PD file created by

RSLogix 500.


Process Control Instruction 19-3

PID - Proportional

Integral Derivative

PID

PID File

Process Variable

Control Variable

Setup Screen

PD8:0

N7:0

N7:1


Table 19.1 Execution Time for the PID Instruction


True


µ s


µ s

False

11.0

µ s

8.9

µ s

It is recommended that you place the PID instruction on a rung without any conditional logic. If conditional logic exists, the Control Variable output remains at its last value, and the CVP CV% term and integral term are both cleared when the rung is false.

NOTE

In order to stop and restart the PID instruction, you need to create a false-to-true rung transition.

The example below shows a PID instruction on a rung with RSLogix 500 programming software.

0047

B3:0

0

PID

PID File

Process Variable

Control Variable

Setup Screen

PD8:0

N7:0

N7:1

When programming, the setup screen provides access to the PID instruction configuration parameters. The illustration below shows the

RSLogix 500 setup screen.



Input Parameters

The table below shows the input parameter addresses, data formats, and types of user program access. See the indicated pages for descriptions of each parameter.

Input Parameter Descriptions Address

SPS - Setpoint

PV - Process Variable

MAXS - Setpoint Maximum

MINS - Setpoint Minimum

OSP - Old Setpoint Value

PD10:0.SPS

user defined

PD10:0.MAXS

PD10:0.MINS

PD10:0.OSP


word (INT) word (INT)

0 to 16383

(1) word (INT) 0 to 16383

-32,768 to +32,767

Type User

Program

Access

For More

Information

control read/write

19-4

control control read/write read/write

19-4

19-5

word (INT) -32,768 to +32,767 control read/write

19-5

word (INT) -32,768 to +32,767 status read only

19-5

OL - Output Limit PD10:0/OL binary 1 = enabled

0 = disabled word (INT) 0 to 100% control read/write

19-6

CVH - Control Variable High

Limit

PD10:0.CVH

control read/write

19-6

CVL - Control Variable Low Limit PD10:0.CVL

word (INT) 0 to 100% control read/write

19-6

(1) The range listed in the table is for when scaling is not enabled. With scaling, the range is from minimum scaled (MINS) to maximum scaled (MAXS).

Setpoint (SPS)

Input Parameter

Descriptions


Access

SPS - Setpoint PD10:0.SPS

word (INT)

0 to 16383

(1) control read/write

(1) The range listed in the table is for when scaling is not enabled. With scaling, the range is from minimum scaled

(MINS) to maximum scaled (MAXS).

The SPS (Setpoint) is the desired control point of the process variable.

Process Variable (PV)

Input Parameter

Descriptions

PV - Process

Variable


Access

user defined word (INT) 0 to 16383 control read/write

The PV (Process Variable) is the analog input variable.



Setpoint MAX (MAXS)

Input

Parameter

Descriptions

Address Data

Format

MAXS - Setpoint

Maximum

PD10:0.MAXS

word

(INT)

Range Type User

Program

Access

-32,768 to +32,767 control read/write

If the SPV is read in engineering units, then the MAXS (Setpoint

Maximum) parameter corresponds to the value of the setpoint in engineering units when the control input is at its maximum value.

Setpoint MIN (MINS)

Input Parameter

Descriptions

MINS - Setpoint

Minimum

Address

PD10:0.MINS

Data

Format

word

(INT)

Range Type User

Program

Access


If the SPV is read in engineering units, then the MINS (Setpoint Minimum) parameter corresponds to the value of the setpoint in engineering units when the control input is at its minimum value.

NOTE

MinS - MaxS scaling allows you to work in engineering units. The deadband, error, and SPV are also displayed in engineering units. The process variable, PV, must be within the range of 0 to 16383. Use of MinS - MaxS does not minimize PID PV resolution.

Scaled errors greater than +32767 or less than -32768 cannot be represented. If the scaled error is greater than +32767, it is represented as

+32767. If the scaled error is less than -32768, it is represented as -32768.

Old Setpoint Value (OSP)

Input Parameter

Descriptions

Address Data

Format

OSP - Old

Setpoint Value

PD10:0.OSP

word

(INT)

Range Type User

Program

Access

-32,768 to +32,767 status read only

The OSP (Old Setpoint Value) is substituted for the current setpoint, if the current setpoint goes out of range of the setpoint scaling (limiting) parameters.



Output Limit (OL)

Output Parameter

Descriptions

OL - Output Limit

Address Data

Format

PD10:0/OL binary

Range

1 = enabled

0 = disabled


Access

control read/write

An enabled (1) value enables output limiting to the values defined in

PD10:0.CVH (Control Variable High) and PD10.0.CVL (Control Variable

Low).

A disabled (0) value disables OL (Output Limiting).

Control Variable High Limit (CVH)


Descriptions

CVH - Control

Variable High Limit


Access

PD10:0.CVH

word (INT) 0 to 100% control read/write

When the output limit bit (PD10:0/OL) is enabled (1), the CVH (Control

Value High) you enter is the maximum output (in percent) that the control variable attains. If the calculated CV exceeds the CVH, the CV is set

(overridden) to the CVH value you entered and the upper limit alarm bit

(UL) is set.

When the output limit bit (PD10:0/OL) is disabled (0), the CVH value you enter determines when the upper limit alarm bit (UL) is set.

If CV exceeds the maximum value, the output is not overridden and the upper limit alarm bit (UL) is set.

Control Variable Low Limit (CVL)


Descriptions

Address Data

Format

CVL - Control

Variable Low Limit

PD10:0.CVL

word

(INT)


Access

0 to 100% control read/write

When the output limit bit (PD10:0/OL) is enabled (1), the CVL (Control

Value Low) you enter is the minimum output (in percent) that the Control

Variable attains. If the calculated CV is below the minimum value, the CV is set (overridden) to the CVL value you entered and the lower limit alarm bit (LL) is set.

When the output limit bit (PD10:0/OL) is disabled (0), the CVL value you enter determines when the lower limit alarm bit (LL) is set. If CV is below the minimum value, the output is not overridden and the lower limit alarm bit (LL) is set.



Output Parameters

Output Parameter Descriptions Address

CV - Control Variable

CVP - Control Variable Percent

SPV - Scaled Process Variable

The table below shows the output parameter addresses, data formats, and types of user program access. See the indicated pages for descriptions of each parameter.

User-defined

PD10:0.CVP

PD10:0.SPV

Data Format Range Type User Program

Access

word (INT) 0 to 16,383 control read/write word (INT) 0 to 100 control read/write word (INT) 0 to 16383 status read only

For More

Information

19-7

19-7

19-7

Control Variable (CV)


Descriptions

Address Data

Format


Access

CV - Control Variable User-defined word (INT) 0 to 16,383 control read/write

The CV (Control Variable) is user-defined. See the ladder rung below.

0000 PID

PID File

Process Variable

Control Variable

Setup Screen

PD10:0

N7:0

N7:1

Control Variable Percent (CVP)


Descriptions

Address Data

Format


Access

CVP - Control Variable Percent PD10:0.CVP

word (INT) 0 to 100 control read/write

CVP (Control Variable Percent) displays the control variable as a percentage. The range is 0 to 100%. If the PD10:0/AM bit is off (automatic mode), this value tracks the control variable (CV) output. Any value written by the programming software is overwritten. If the PD10:0/AM bit is on (MANUAL mode), this value can be set by the programming software, and the control variable output tracks the control variable percent value.

Scaled Process Variable (SPV)

Input Parameter

Descriptions

Address Data

Format


Access

SPV - Scaled Process Variable PD10:0.SPV word (INT) 0 to 16383 status read only

The SPV (Scaled Process Variable) is the analog input variable. If scaling is enabled, the range is the minimum scaled value (MinS) to maximum scaled value (MaxS).

If the SPV is configured to be read in engineering units, then this parameter corresponds to the value of the process variable in engineering

units. See Analog I/O Scaling on page 19-17 for more information on

scaling.



Tuning Parameters

Tuning Parameter

Descriptions

KC - Controller Gain - K c

TI - Reset Term - T i

TD - Rate Term - T d

TM - Time Mode

LUT - Loop Update Time

PD10:0.KC

PD10:0.Ti

PD 10:0.TD

PD10:0.TM

PD10:0.LUT

ZCD - Zero Crossing Deadband PD10:0.ZCD

FF - Feed Forward Bias PD10:0.FF

SE - Scaled Error

AM - Automatic/Manual

CM - Control Mode

DB - PV in Deadband

PD10:0.SE

PD10:0/AM

PD10:0/CM

PD10:0/DB

RG - PLC 5 Gain Range

SC - Setpoint Scaling

TF - Loop Update Too Fast

DA - Derivative Action Bit

UL - CV Upper Limit Alarm

LL - CV Lower Limit Alarm

SP - Setpoint Out of Range

PV - PV Out of Range

DN - Done

EN - Enable

IS - Integral Sum

PD10:0/RG

PD10:0/SC

PD10:0/TF

PD10:0/DA

PD10:0/UL

PD10:0/LL

PD10:0/SP

PD10:0/PV

PD10:0/DN

PD10:0/EN

PD10:0.IS

AD - Altered Derivative Term

The table below shows the tuning parameter addresses, data formats, and types of user program access. See the indicated pages for descriptions of each parameter.

Address

PD10:0.AD

word (INT) word (INT) word (INT) binary word (INT) word (INT) word (INT) word (INT) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) binary (bit) long word

(32-bit INT) long word

(32-bit INT)


0 to 32,767

0 to 32,767

0 to 32,767

Type User

Program

Access

control read/write control control read/write read/write

For More

Information

19-9

19-9

19-9

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

0 or 1

1 to 1024 control read/write control read/write

0 to 32,767 control read/write


19-10

19-10

19-11

19-11

-32,768 to +32,767 status read only


0 or 1

0 or 1 control status read/write read/write

19-11

19-12

19-12

19-12

0 or 1

0 or 1

-2,147,483,648 to

2,147,483,647

-2,147,483,648 to

2,147,483,647 control read/write

19-13

control read/write

19-13

status read/write control read/write status read/write status read/write

status read/write status read/write status status status status read only read only read/write read only

19-13

19-14

19-14

19-14

19-14

19-15

19-15

19-15

19-15

19-15



Controller Gain (K

c

)


Descriptions

KC - Controller Gain - K c

Address

PD10:0.KC


word (INT)


Access


Gain K c

(word 3) is the proportional gain, ranging from 0 to 3276.7 (when

RG = 0), or 0 to 327.67 (when RG = 1). Set this gain to one-half the value needed to cause the output to oscillate when the reset and rate terms

(below) are set to zero.

NOTE

Controller gain is affected by the reset and gain range

(RG) bit. For information, see PLC 5 Gain Range (RG) on page 19-13.

Reset Term (T

i

)


Descriptions

TI - Reset Term - T i

Address Data

Format

PD10:0.Ti

word

(INT)

Range

0 to 32,767


Access

control read/write

Reset T i

(word 4) is the Integral gain, ranging from 0 to 3276.7 (when RG

= 0), or 327.67 (when RG = 1) minutes per repeat. Set the reset time equal to the natural period measured in the above gain calibration. A value of 1 adds the maximum integral term into the PID equation.

NOTE

Reset term is affected by the reset and gain range (RG) bit.

For information, see PLC 5 Gain Range (RG) on page 19-13.

Rate Term (T

d

)


Descriptions

TD - Rate Term - T d

Address

PD 10:0.TD

Data Format

word (INT)


Access


Rate T d

(word 5) is the Derivative term. The adjustment range is 0 to

327.67 minutes. Set this value to 1/8 of the integral gain T i

.

NOTE

This word is not effected by the reset and gain range (RG)

bit. For information, see PLC 5 Gain Range (RG) on page 19-13.



Time Mode (TM)


Descriptions

TM - Time Mode

Address Data

Format

PD10:0.TM

binary

Range

0 or 1


Access

control read/write

The time mode bit specifies when the PID is in timed mode (1) or STI mode (0). This bit can be set or cleared by instructions in your ladder program.

When set for timed mode, the PID updates the CV at the rate specified in the loop update parameter (PD10:0.LUT).

When set for STI mode, the PID updates the CV every time the PID instruction is scanned in the control program. When you select STI, program the PID instruction in the STI interrupt subroutine. The STI routine should have a time interval equal to the setting of the PID “loop update” parameter (PD10:0.LUT). Set the STI period in word STI:0.SPM.

For example, if the loop update time contains the value 10 (for 100 ms), then the STI time interval must also equal 100 (for 100 ms).

NOTE

When using timed mode, your processor scan time should be at least ten times faster than the loop update time to prevent timing inaccuracies or disturbances.

Loop Update Time (LUT)


Descriptions


LUT - Loop Update Time PD10:0.LUT

word (INT) 1 to 1024

Type

control

User Program

Access

read/write

The loop update time (word 13) is the time interval between PID calculations. The entry is in 0.01 second intervals. Enter a loop update time five to ten times faster than the natural period of the load. The natural period of the load is determined by setting the reset and rate parameters to zero and then increasing the gain until the output begins to oscillate. When in STI mode, this value must equal the STI time interval value loaded in STI:0.SPM. The valid range is 0.01 to 10.24 seconds.



Zero Crossing Deadband (ZCD)


Descriptions

ZCD - Zero Crossing

Deadband

Address Data

Format


Access

PD10:0.ZCD


The deadband extends above and below the setpoint by the value entered. The deadband is entered at the zero crossing of the process variable and the setpoint. This means that the deadband is in effect only after the process variable enters the deadband and passes through the setpoint.

The valid range is 0 to the scaled maximum, or 0 to 16,383 when no scaling exists.

Feed Forward Bias (FF)


Descriptions

FF - Feed Forward

Bias

Address Data

Format

PD10:0.FF

word

(INT)


Access


The feed forward bias is used to compensate for disturbances that may affect the CV output.

Scaled Error (SE)


Descriptions

Address Data

Format


Access

SE - Scaled Error PD10:0.SE

word (INT) -32,768 to +32,767 status read only

Scaled error is the difference between the process variable and the setpoint. The format of the difference (E = SP-PV or E = PV-SP) is

determined by the control mode (CM) bit. See Control Mode (CM) on page 19-12.



Automatic / Manual (AM)


Descriptions


AM - Automatic/Manual PD10:0/AM binary (bit) 0 or 1

Type

control

User Program

Access

read/write

The auto/manual bit can be set or cleared by instructions in your ladder program. When off (0), it specifies automatic operation. When on (1), it specifies manual operation. In automatic operation, the instruction controls the control variable (CV). In manual operation, the user/control program controls the CV. During tuning, set this bit to manual.

NOTE

Output limiting is also applied when in manual.

Control Mode (CM)


Descriptions


CM - Control Mode PD10:0/CM binary (bit)

Range

0 or 1

Type

control

User Program

Access

read/write

Control mode, or forward-/reverse-acting, toggles the values E=SP-PV and

E=PV-SP.

Forward acting (E=PV-SP) causes the control variable to increase when the process variable is greater than the setpoint.

Reverse acting (E=SP-PV) causes the control variable to decrease when the process variable is greater than the setpoint.

PV in Deadband (DB)


Descriptions


DB - PV in Deadband PD10:0/DB binary (bit)

Range

0 or 1

Type

status

User Program

Access

read/write

This bit is set (1) when the process variable is within the zero-crossing deadband range.



PLC 5 Gain Range (RG)


Descriptions


RG - PLC 5 Gain Range PD10:0/RG binary (bit) 0 or 1

Type

control

User Program

Access

read/write

When set (1), the reset (TI) and gain range enhancement bit (RG) causes the reset minute/repeat value and the gain multiplier (KC) to be divided by a factor of 10. That means a reset multiplier of 0.01 and a gain multiplier of 0.01.

When clear (0), this bit allows the reset minutes/repeat value and the gain multiplier value to be evaluated with a reset multiplier of 0.1 and a gain multiplier of 0.1.

Example with the RG bit set: The reset term (TI) of 1 indicates that the integral value of 0.01 minutes/repeat (0.6 seconds/repeat) is applied to the PID integral algorithm. The gain value (KC) of 1 indicates that the error is multiplied by 0.01 and applied to the PID algorithm.

Example with the RG bit clear: The reset term (TI) of 1 indicates that the integral value of 0.1 minutes/repeat (6.0 seconds/repeat) is applied to the

PID integral algorithm. The gain value (KC) of 1 indicates that the error is multiplied by 0.1 and applied to the PID algorithm.

NOTE

The rate multiplier (TD) is not affected by this selection.

Setpoint Scaling (SC)


Descriptions


SC - Setpoint Scaling PD10:0/SC binary (bit) 0 or 1

Type

control

User Program

Access

read/write

The SC bit is cleared when setpoint scaling values are specified.

Loop Update Too Fast (TF)


Descriptions

TF - Loop Update Too

Fast

Address

PD10:0/TF

Data Format

binary (bit)


Access

0 or 1 status read/write

The TF bit is set by the PID algorithm if the loop update time specified cannot be achieved by the controller due to scan time limitations.

If this bit is set, correct the problem by updating your PID loop at a slower rate or move the PID instruction to an STI interrupt routine. Reset and rate gains will be in error if the instruction operates with this bit set.



Derivative Action Bit (DA)


Descriptions


DA - Derivative Action Bit PD10:0/DA binary (bit) 0 or 1

Type

control

User Program

Access

read/write

When set (1), the derivative (rate) action (DA) bit causes the derivative

(rate) calculation to be evaluated on the error instead of the process variable (PV). When clear (0), this bit allows the derivative (rate) calculation to be evaluated where the derivative is performed on the PV.

CV Upper Limit Alarm (UL)


Descriptions


UL - CV Upper Limit Alarm PD10:0/UL binary (bit) 0 or 1

Type

status

User Program

Access

read/write

The control variable upper limit alarm bit is set when the calculated CV output exceeds the upper CV limit.

CV Lower Limit Alarm (LL)


Descriptions


LL - CV Lower Limit Alarm PD10:0/LL binary (bit) 0 or 1

Type

status

User Program

Access

read/write

The control variable lower limit alarm bit is set (1) when the calculated

CV output is less than the lower CV limit.

Setpoint Out Of Range (SP)


Descriptions


Access

SP - Setpoint Out of Range PD10:0/SP binary (bit) 0 or 1 status read/write

This bit is set (1) when the setpoint:

• exceeds the maximum scaled value, or

• is less than the minimum scaled value.



PV Out Of Range (PV)


Descriptions


PV - PV Out of Range PD10:0/PV binary (bit)

Range

0 or 1

Type

status

User Program

Access

read/write

The process variable out of range bit is set (1) when the unscaled process variable

• exceeds 16,383, or

• is less than zero.

Done (DN)


Descriptions

DN - Done

Address

PD10:0/DN

Data Format

binary (bit)


Access


The PID done bit is set (1) for one scan when the PID algorithm is computed. It resets (0) whenever the instruction is scanned and the PID algorithm was not computed (applies to timed mode only).

Enable (EN)


Descriptions

EN - Enable

Address

PD10:0/EN

Data Format

binary (bit)


Access


The PID enabled bit is set (1) whenever the PID instruction is enabled. It follows the rung state.

Integral Sum (IS)


Descriptions


IS - Integral Sum PD10:0.IS

long word

(32-bit INT)

-2,147,483,648 to

2,147,483,647


Access

status read/write

This is the result of the integration

Kc

T

I

∫

d t

.

Altered Derivative Term (AD)


Descriptions


AD - Altered

Derivative Term

PD10:0.AD

long word

(32-bit INT)

-2,147,483,648 to

2,147,483,647


Access

status read only

This long word is used internally to track the change in the process variable within the loop update time.



Runtime Errors

Error code 0036 appears in the status file when a PID instruction runtime error occurs. Code 0036 covers the following PID error conditions, each of which has been assigned a unique single byte code value that appears in the MSB of the second word of the control block.

Error Code Description of Error Condition or Conditions

11H

12H

13H

1. Loop update time

D t

> 1024

2. Loop update time

D t

= 0

Proportional gain

K c

< 0

Integral gain (reset)

T i

< 0

14H

15H

23H

Derivative gain (rate)

T d

< 0

Feed Forward Bias (FF) is out-of-range.

31H

Scaled setpoint min

MinS > Scaled setpoint max MaxS

If you are using setpoint scaling and

MinS > setpoint SP > MaxS, or

If you are not using setpoint scaling and

0 > setpoint SP > 16383,

41H

51H

52H

53H

Corrective Action

Change loop update time 0 < D t

Change proportional gain K c

Change integral gain (reset) T i

< 1024 to 0 < K to 0 < T

Change derivative gain (rate) T d

Change FF so it is within the range -16383 to +16383.

Change scaled setpoint min MinS to

-32768 < MinS < MaxS < +32767

If you are using setpoint scaling, then change the setpoint SP to MinS < SP < MaxS, or

If you are not using setpoint scaling, then change the setpoint SP to 0 < SP < 16383.

c i to 0 < T d then during the initial execution of the PID loop, this error occurs and bit 11 of word 0 of the control block is set.

However, during subsequent execution of the PID loop if an invalid loop setpoint is entered, the PID loop continues to execute using the old setpoint, and bit 11 of word 0 of the control block is set.

Scaling Selected

1. Deadband < 0, or

Scaling Deselected

1. Deadband < 0, or

2. Deadband

>

(MaxS – MinS)

1. Output high limit < 0, or

2. Output high limit > 100

3. Deadband > 16383

Scaling Selected

Change deadband to

0 < deadband <

(MaxS - MinS) < 16383

Change output high limit to

0 < output high limit < 100

1. Output low limit < 0, or

2. Output low limit > 100

Output low limit > output high limit

Scaling Deselected

Change deadband to

0 < deadband < 16383

Change output low limit to

0 < output low limit < output high limit < 100

Change output low limit to

0 < output low limit < output high limit < 100


Analog I/O Scaling


To configure an analog input for use in a PID instruction, the analog data must be scaled to match the PID instruction parameters. In the MicroLogix

1200 and 1500, the process variable (PV) in the PID instruction is designed to work with a data range of 0 to 16,383. The 1769 Compact I/O analog modules (1769-IF4 and 1769-OF2) are capable of on-board scaling.

Scaling data is required to match the range of the analog input to the input range of the PID instruction. The ability to perform scaling in the

I/O modules reduces the amount of programming required in the system and makes PID setup much easier.

The example shows a 1769-IF4 module. The IF4 has 4 inputs, which are individually configurable. In this example, analog input 0 is configured for

0 to 10V and is scaled in engineering units. Word 0 is not being used in a

PID instruction. Input 1 (word 1) is configured for 4 to 20 mA operation with scaling configured for a PID instruction. This configures the analog data for the PID instruction.

Field Device Input Signal

> 20.0 mA

20.0 mA

4.0 mA

< 4.0 mA

Analog Register Scaled Data

16,384 to 17,406

16,383

0

-819 to -1

The analog configuration screen is accessed from within RSLogix 500.

Simply double click on the I/O configuration item in the “Controller” folder, and then double click on the specific I/O module.

The configuration for the analog output is virtually identical. Simply address the PID control variable (CV) to the analog output address and configure the analog output to “Scaled for PID” behavior.



Application Notes

The following paragraphs discuss:

•

Input/Output Ranges

•

Scaling to Engineering Units

•

Zero-crossing Deadband

•

Output Alarms

•

Output Limiting with Anti-reset Windup

•

The Manual Mode

•

Feed Forward

ATTENTION

!

Do not alter the state of any PID control block value unless you fully understand its function and how it will affect your process. Unexpected operation could result with possible equipment damage and/or personal injury.

Input/Output Ranges

The input module measuring the process variable (PV) must have a full scale binary range of 0 to 16383. If this value is less than 0 (bit 15 set), then a value of zero is used for PV and the “Process var out of range” bit is set (bit 12 of word 0 in the control block). If the process variable is greater than 16383 (bit 14 set), then a value of 16383 is used for PV and the “Process var out of range” bit is set.

The Control Variable, calculated by the PID instruction, has the same range of 0 to 16383. The Control Output (word 16 of the control block) has the range of 0 to 100%. You can set lower and upper limits for the instruction’s calculated output values (where an upper limit of 100% corresponds to a Control Variable limit of 16383).



Scaling to Engineering Units

Scaling lets you enter the setpoint and zero-crossing deadband values in engineering units, and display the process variable and error values in the same engineering units. Remember, the process variable PV must still be within the range 0 to 16383. The PV is displayed in engineering units, however.

Select scaling as follows:

1. Enter the maximum and minimum scaling values MaxS and MinS in the PID control block. The MinS value corresponds to an analog value of zero for the lowest reading of the process variable. MaxS corresponds to an analog value of 16383 for the highest reading.

These values reflect the process limits. Setpoint scaling is selected by entering a non-zero value for one or both parameters. If you enter the same value for both parameters, setpoint scaling is disabled.

For example, if measuring a full scale temperature range of -73°C

(PV=0) to

+

1156°C (PV=16383), enter a value of -73 for MinS and 1156 for MaxS. Remember that inputs to the PID instruction must be 0 to

16383. Signal conversions could be as follows:

Example Values

Process limits

Transmitter output (if used)

Output of analog input module

PID instruction, MinS to MaxS

-73 to

+

1156°C

+4 to +20 mA

0 to 16383

-73 to

+

1156°C

2. Enter the setpoint (word 2) and deadband (word 9) in the same scaled engineering units. Read the scaled process variable and scaled error in these units as well. The control output percentage (word 16) is displayed as a percentage of the 0 to 16383 CV range. The actual value transferred to the CV output is always between 0 and 16383.

When you select scaling, the instruction scales the setpoint, deadband, process variable, and error. You must consider the effect on all these variables when you change scaling.



Zero-Crossing Deadband DB

The adjustable deadband lets you select an error range above and below the setpoint where the output does not change as long as the error remains within this range. This lets you control how closely the process variable matches the setpoint without changing the output.

+DB

SP

-DB

Error range

Time

Zero-crossing is deadband control that lets the instruction use the error for computational purposes as the process variable crosses into the deadband until it crosses the setpoint. Once it crosses the setpoint (error crosses zero and changes sign) and as long as it remains in the deadband, the instruction considers the error value zero for computational purposes.

Select deadband by entering a value in the deadband storage word (word

9) in the control block. The deadband extends above and below the setpoint by the value you enter. A value of zero inhibits this feature. The deadband has the same scaled units as the setpoint if you choose scaling.

Output Alarms

You may set an output alarm on the control variable at a selected value above and/or below a selected output percent. When the instruction detects that the control variable has exceeded either value, it sets an alarm bit (bit LL for lower limit, bit UL for upper limit) in the PID instruction.

Alarm bits are reset by the instruction when the control variable comes back inside the limits. The instruction does not prevent the control variable from exceeding the alarm values unless you select output limiting.

Select upper and lower output alarms by entering a value for the upper alarm (CVH) and lower alarm (CVL). Alarm values are specified as a percentage of the output. If you do not want alarms, enter zero and 100% respectively for lower and upper alarm values and ignore the alarm bits.



Output Limiting with Anti-Reset Windup

You may set an output limit (percent of output) on the control variable.

When the instruction detects that the control variable has exceeded a limit, it sets an alarm bit (bit LL for lower limit, bit UL for upper limit), and prevents the control variable from exceeding either limit value. The instruction limits the control variable to 0 and 100% if you choose not to limit.

Select upper and lower output limits by setting the limit enable bit (bit

OL), and entering an upper limit (CVH) and lower limit (CVL). Limit values are a percentage (0 to 100%) of the control variable.

The difference between selecting output alarms and output limits is that you must select output limiting to enable limiting. Limit and alarm values are stored in the same words. Entering these values enables the alarms, but not limiting. Entering these values and setting the limit enable bit enables limiting and alarms.

Anti-reset windup is a feature that prevents the integral term from becoming excessive when the control variable reaches a limit. When the sum of the PID and bias terms in the control variable reaches the limit, the instruction stops calculating the integral sum until the control variable comes back in range. The integral sum is contained in element, IS.

The Manual Mode

In the MANUAL mode, the PID algorithm does not compute the value of the control variable. Rather, it uses the value as an input to adjust the integral sum (IS) so that a smooth transfer takes place upon re-entering the AUTO mode.

In the MANUAL mode, the programmer allows you to enter a new CV value from 0 to 100%. This value is converted into a number from 0 to

16383 and written to the Control Variable address. If your ladder program sets the manual output level, design your ladder program to write to the

CV address when in the MANUAL mode. Remember that the new CV value is in the range of 0 to 16383, not 0 to 100. Writing to the CV percent

(CVP) with your ladder program has no effect in the MANUAL mode.

PID Rung State

If the PID rung is false, the integral sum (IS) is cleared and CV remains in its last state.



Feed Forward or Bias

Applications involving transport lags may require that a bias be added to the CV output in anticipation of a disturbance. This bias can be accomplished using the processor by writing a value to the Feed Forward

Bias element (word FF). (See page 19-11.) The value you write is added to

the output, allowing a feed forward action to take place. You may add a bias by writing a value between -16383 and +16383 to word 6 with your programming terminal or ladder program.

Application Examples

PID Tuning

PID tuning requires a knowledge of process control. If you are inexperienced, it will be helpful if you obtain training on the process control theory and methods used by your company.

There are a number of techniques that can be used to tune a PID loop.

The following PID tuning method is general and limited in terms of handling load disturbances. When tuning, we recommend that changes be made in the MANUAL mode, followed by a return to AUTO. Output limiting is applied in the MANUAL mode.

NOTE

•

This method requires that the PID instruction controls a non-critical application in terms of personal safety and equipment damage.

•

The PID tuning procedure may not work for all cases.

It is strongly recommended to use a PID Loop tuner package for the best result (i.e. RSTune, Rockwell

Software catalog number 9323-1003D).



Procedure

1. Create your ladder program. Make certain that you have properly scaled your analog input to the range of the process variable PV and that you have properly scaled your control variable CV to your analog output.

2. Connect your process control equipment to your analog modules.

Download your program to the processor. Leave the processor in the program mode.

ATTENTION

!

Ensure that all possibilities of machine motion have been considered with respect to personal safety and equipment damage. It is possible that your output CV may swing between 0 and 100% while tuning.

NOTE

If you want to verify the scaling of your continuous system and/or determine the initial loop update time of

your system, go to the procedure on page 19-25.

3. Enter the following values: the initial setpoint SP value, a reset T i of 0, a rate T d

of 0, a gain K c of 1, and a loop update of 5.

Set the PID mode to STI or Timed, per your ladder diagram. If STI is selected, ensure that the loop update time equals the STI time interval.

Enter the optional settings that apply (output limiting, output alarm,

MaxS - MinS scaling, feed forward).

4. Get prepared to chart the CV, PV, analog input, or analog output as it varies with time with respect to the setpoint SP value.

5. Place the PID instruction in the MANUAL mode, then place the processor in the RUN mode.

6. While monitoring the PID display, adjust the process manually by writing to the CO percent value.

7. When you feel that you have the process under control manually, place the PID instruction in the AUTO mode.

8. Adjust the gain while observing the relationship of the output to the setpoint over time.

9. When you notice that the process is oscillating above and below the setpoint in an even manner, record the time of 1 cycle. That is, obtain the natural period of the process.

Natural Period

≅

4x deadtime

Record the gain value. Return to the MANUAL mode (stop the process if necessary).



10. Set the loop update time (and STI time interval if applicable) to a value of 5 to 10 times faster than the natural period.

For example, if the cycle time is 20 seconds, and you choose to set the loop update time to 10 times faster than the natural rate, set the loop update time to 200, which would result in a 2-second rate.

11. Set the gain K c value to 1/2 the gain needed to obtain the natural period of the process. For example, if the gain value recorded in step

9 was 80, set the gain to 40.

12. Set the reset term T i to approximate the natural period. If the natural period is 20 seconds, as in our example, you would set the reset term to 3 (0.3 minutes per repeat approximates 20 seconds).

13. Now set the rate T d equal to a value 1/8 that of the reset term. For our example, the value 4 is used to provide a rate term of 0.04 minutes per repeat.

14. Place the process in the AUTO mode. If you have an ideal process, the PID tuning is complete.

15. To make adjustments from this point, place the PID instruction in the

MANUAL mode, enter the adjustment, then place the PID instruction back in the AUTO mode.

This technique of going to MANUAL, then back to AUTO, ensures that most of the “gain error” is removed at the time each adjustment is made. This allows you to see the effects of each adjustment immediately. Toggling the PID rung allows the PID instruction to restart itself, eliminating all of the integral buildup. You may want to toggle the PID rung false while tuning to eliminate the effects of previous tuning adjustments.



Verifying the Scaling of Your Continuous System

To ensure that your process is linear, and that your equipment is properly connected and scaled, do the following:

1. Place the PID instruction in MANUAL and enter the following parameters:

– type:

0

for MinS

– type:

100

for MaxS

– type:

0

for CO%

2. Enter the REM RUN mode and verify that PV=0.

3. Type:

20

in CO%

4. Record the PV = _______

5. Type:

40

in CO%.


7. Type:

60

in CO%.


9. Type:

80

in CO%.

10. Record the PV = _______

11. The values you recorded should be offset from CO% by the same amount. This proves the linearity of your process. The following example shows an offset progression of fifteen.

– CO 20% = PV 35%

– CO 40% = PV 55%

– CO 60% = PV 75%

– CO 80% = PV 95%

If the values you recorded are not offset by the same amount:

•

Either your scaling is incorrect, or

• the process is not linear, or

• your equipment is not properly connected and/or configured.

Make the necessary corrections and repeat steps 2-10.



Determining the Initial Loop Update Time

To determine the approximate loop update time that should be used for your process, perform the following:

1. Place the normal application values in MinS and MaxS.

2. Type:

50

in CO%.

3. Type:

60

in CO% and immediately start your stopwatch.

4. Watch the PV. When the PV starts to change, stop your stopwatch.

Record this value. It is the deadtime.

5. Multiply the deadtime by 4. This value approximates the natural period. For example, if deadtime = 3 seconds, then 4 x 3 = 12 seconds (

≅ natural period)

6. Divide the value obtained in step 5 by 10. Use this value as the loop updated time. For example, if: natural period = 12 seconds, then 12/10 = 1.2 seconds.

Therefore, the value 120 would be entered as the loop update time.

(120 x 10 ms = 1.2 seconds)

7. Enter the following values: the initial setpoint SP value, a reset T i of 0, a rate T d

of 0, a gain K c of 1, and the loop update time determined in step 17.

Set the PID mode to STI or Timed, per your ladder diagram. If STI is selected, ensure that the loop update time equals the STI time interval.

Enter the optional settings that apply (output limiting, output alarm,

MaxS - MinS scaling, feed forward).

8. Return to page 19-23 and complete the tuning procedure starting with

step 4.


1

Chapter

20


General Information

This chapter contains general information about the ASCII instructions and explains how they function in your control program. This chapter is arranged into the following sections:

•

Instruction Types and Operation on page 20-2

•

Protocol Overview on page 20-4

•

String (ST) Data File on page 20-5

•

Control Data File on page 20-6


The ASCII instructions are arranged so that the Write instructions precede the Read instructions.

Instruction

ACL - ASCII Clear Buffer

AIC - Integer to String

AWA - ASCII Write with

Append

AWT - ASCII Write

ABL - Test Buffer for Line

ACB - Number of Characters in Buffer

ACI - String to Integer

ACN - String Concatenate

AEX - String Extract

Function

Clear the receive and/or transmit buffers.

Convert an integer value to a string.

Valid Controller(s)

•

•

MicroLogix 1200

MicroLogix 1500 Series B, FRN 4 or later

Page

20-7

20-8

20-9

Write a string with user-configured characters appended.

Write a string.

Determine the number of characters in the buffer, up to and including the end-of-line character.

20-11

•

•



20-14

20-15

Determine the total number of characters in the buffer.

Convert a string to an integer value.

20-16

Link two strings into one.

Extract a portion of a string to create a new string.

AHL - ASCII Handshake Lines Set or reset modem handshake lines.

ARD - ASCII Read Characters Read characters from the input buffer and place them into a string.

20-18

20-19

20-20

20-22

ARL - ASCII Read Line Read one line of characters from the input buffer and place them into a string.

ASC - String Search Search a string.

ASR - ASCII String Compare Compare two strings.

20-23

20-25

20-26


20-2 ASCII Instructions

Instruction Types and

Operation

There are two types of ASCII instructions, ASCII string control and ASCII port control. The string control instruction type is used for manipulating data and executes immediately. The port control instruction type is used for transmitting data and makes use of the ASCII queue. More details are provided below.

ASCII String Control

These instructions are used to manipulate string data. When a string control instruction is encountered in a ladder logic program, it executes immediately. It is never sent to the ASCII queue to wait for execution. The following tables list the ASCII string control instructions used by the

MicroLogix 1200 and 1500 controllers:

MicroLogix 1200 Series A

AIC (Integer to String)

MicroLogix 1200 Series B, FRN 3 and later


ACI (String to Integer)

ACN (String Concatenate)

AEX (String Extract)

AIC (Integer to String)

ASC (String Search)

ASR (ASCII String Compare)

ASCII Port Control

These instructions use or alter the communication channel for receiving or transmitting data. The following tables list the ASCII port control instructions used by the MicroLogix 1200 and 1500 controllers:

MicroLogix 1200 Series A

(1)

ACL (ASCII Clear Buffer)

AWA (ASCII Write with Append)

AWT (ASCII Write)

(1) For the MicroLogix 1200 Series A, these instructions only transmit data.



ABL (Test Buffer for Line)

ACB (Number of Characters in Buffer)

ACL (ASCII Clear Buffer)

AHL (ASCII Handshake Lines)

ARD (ASCII Read Characters)

ARL (ASCII Read Line)

AWA (ASCII Write with Append)

AWT (ASCII Write)

When the ACL (ASCII Clear Buffer) instruction is encountered in a ladder logic program, it executes immediately and causes all instructions to be removed from the ASCII queue, including stopping execution of the ASCII instruction currently executing. The ER (error) bit is set for each instruction that is removed from the ASCII queue.


ASCII Instructions 20-3

When any of the other port control instructions are encountered in a ladder logic program, it may or may not execute immediately depending on the contents of the ASCII queue. The ASCII queue is a FIFO (first-in, first-out) queue which can contain up to 16 instructions. The ASCII queue operates as follows:

•

When the instruction is encountered on a rung and the ASCII queue is empty, the instruction executes immediately. It may take several program scans for the instruction to complete.

•

When the instruction is encountered on a rung and there are from 1 to

15 instructions in the ASCII queue, the instruction is put into the ASCII queue and is executed when the preceding instructions are completed. If the ASCII queue is full, the instruction waits until the next program scan to determine if it can enter the ASCII queue. The controller continues executing other instructions while the ASCII port control instruction is waiting to enter the queue.

Programming ASCII Instructions

When programming ASCII output instructions, always precede the ASCII instruction with conditional logic that detects when new data needs to be sent or, send data on a time interval. If sent on a time interval, use an interval of 0.5 second or greater. Do not continuously generate streams of

ASCII data out of a communications port.

IMPORTANT

If ASCII write instructions execute continuously, you may not be able to re-establish communications with RSLogix

500 when the controller is placed into the RUN mode.



Protocol Overview

MicroLogix 1200 Series A and later, and

MicroLogix 1500 Series B, FRN 4 or later

The AWA and AWT instructions only successfully transmit an ASCII string out of the RS-232 port when the channel is configured for DF1

Full-Duplex protocol. If the RS-232 port is configured for any protocol other than DF1 Full-Duplex, the AWA and AWT instructions will error out with an error code of 9.

DF1 Full-Duplex packets take precedence over ASCII strings, so if an AWA or AWT instruction is triggered while a DF1 Full-Duplex packet is being transmitted, the ASCII instruction will error out with an error code of 5.

See Table E.2 on page E-5 for the DF1 Full-Duplex protocol parameters

that you set via the Channel 0 configuration screens in your programming software. Configuration of the two append characters for the AWA instruction can be found in the General tab of Channel Configuration option in RSLogix 500.

MicroLogix 1200 Series B, FRN 3 and later, and


For the AWA and AWT instructions, you can use DF1 Full-Duplex protocol as described above. To use the full ASCII instruction set, use ASCII protocol as described below.

See Table E.9 on page E-14 for the ASCII parameters that you set via the

Channel 0 (and Channel 1 for the 1764-LRP) configuration screens in your programming software. Configuration of the two append characters for the AWA instruction can be found in the General tab of Channel

Configuration option in RSLogix 500.



String (ST) Data File


The string data file is used by the ASCII instructions to store ASCII character data. The ASCII data can be accessed by the source and destination operands in the ASCII instructions. The string data file can also be used by the copy (COP) and move (MOV, MVM) instructions.

String files consist of 42-word elements. One string file element is shown below. You can have up to 256 of these elements in the string file.

Table 20.1 String Data File Structure

0

1

2

↓

40

41

String Element

Bit 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Word

upper byte lower byte

String Length - number of characters (range is from 0 to 82) character 0 character 2

↓ character 78 character 80 character 1 character 3

↓ character 79 character 81

Addressing String Files

The addressing scheme for the string data file is shown below.

Format

STf:e.s

Explanation f

ST

String file

File number The valid file number range is from 3 to 255.

: e

Element delimiter

Element number The valid element number range is from 0 to 255.

Each element is 42 words in length as shown in Table 20.1.

.

s

Subelement delimiter

Subelement number The valid subelement number range is from 0 to 41. You can also specify .LEN for word 0.

The subelement represents a word address.

Examples: ST9:2

ST17:1.LEN

String File 9, Element 2

String File 17, Element 1, LEN Variable



Control Data File


The control data element is used by ASCII instructions to store control information required to operate the instruction. The control data element for ASCII instructions includes status and control bits, an error code byte, and two character words as shown below:

Table 20.2 ASCII Instructions Control Data File Elements

Control Element

Word 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

0

1

EN

(1)

EU

(2)

DN

(3)

EM

(4)

ER

(5)

UL

(6)

RN

(7)

FD

(8) Error Code Byte

Number of characters specified to be sent or received (LEN)

2 Number of characters actually sent or received (POS)

(1) EN = Enable Bit - indicates that an instruction is enabled due to a false-to-true transition. This bit remains set until the instruction completes execution or generates an error.

(2) EU = Queue Bit - when set, indicates that an ASCII instruction was placed in the ASCII queue. This action is delayed if the queue is already filled.

(3) DN = Asynchronous Done Bit - is set when an instruction successfully completes its operation.

(4) EM = Synchronous Done Bit - not used

(5) ER = Error Bit - when set, indicates that an error occurred while executing the instruction.

(6) UL = Unload Bit - when this bit is set by the user, the instruction does not execute. If the instruction is already executing, operation ceases. If this bit is set while an instruction is executing, any data already processed is sent to the destination and any remaining data is not processed. Setting this bit will not cause instructions to be removed from the ASCII queue. This bit is only examined when the instruction is ready to start executing.

(7) RN = Running Bit - when set, indicates that the queued instruction is executing.

(8) FD = Found Bit - when set, indicates that the instruction has found the end-of-line or termination character in the buffer. (only used by the ABL and ACB instructions)

Addressing Control Files

The addressing scheme for the control data file is shown below.

Format

R:e.s/b

Explanation f

R

Control file

File number The valid file number range is from 3 to 255.

.

s

: e

Element delimiter

Element number The valid element number range is from 0 to 255.

Each element is 3 words in length as shown in Table 20.2.

Subelement delimiter

Subelement number The valid subelement number range is from 0 to 2. You can also specify .LEN or .POS.

/

Bit delimiter

b

Bit number

Examples: R6:2

R6:2.0/13

R18:1.LEN

R18:1.POS

The valid bit number range is from 0 to 15.

The bit number is the bit location within the string file element.

Bit level addressing is not available for words 1 and 2 of the control element.

Element 2, control file 6

Bit 13 in sub-element 0 of element 2, control file 6

Specified string length of element 1, control file 1 8

Actual string length of element 1, control file 18



ACL - ASCII Clear

Buffers

Ascii Clear Buffers

Channel

Transmit Buffer

Receive Buffer

0

Yes

No


Table 20.3 Execution Time for the ACL Instruction


True

MicroLogix 1200 clear buffers: both 249.1

µ s receive 28.9

µ s transmit 33.6

µ s

MicroLogix 1500 Series B, FRN 4 or later clear buffers: both 203.9

µ s receive 24.7

µ s transmit 29.1

µ s

False

0.0

µ s

0.0

µ s

The ACL instruction clears the Receive and/or Transmit buffer(s). This instruction also removes instructions from ASCII queue.

This instruction executes immediately upon the rung transitioning to a true state. Any ASCII transmissions in progress are terminated when the

ACL instruction executes.

NOTE

The ASCII queue may contain up to 16 instructions that are waiting to run.

Entering Parameters

Enter the following parameters when programming this instruction:

•

Channel is the number of the RS-232 port, Channel 0. (For the

1764-LRP only, you can select either Channel 0 or Channel 1).

•

Receive Buffer clears the Receive buffer when set to “Yes” and removes the Receive ASCII port control instructions (ARL and ARD) from the ASCII queue.

•

Transmit Buffer clears the Transmit buffer when set to “Yes” and removes the Transmit ASCII port control instructions (AWA and AWT) from the ASCII queue.




Table 20.4 ACL Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Receive Buffer

Transmit Buffer

(1) The Control data file is the only valid file type for the Control Element.

•

•

•

•

•

•

Instruction Operation

When Clear Receive Buffer and Clear Transmit Buffer are both set to Yes, all Receive and Transmit instructions (ARL, ARD, AWA, and AWT) are removed from the ASCII queue.

When instructions are removed from the ASCII queue, the following bits are set: ER = 1, RN = 0, EU = 0, and ERR = 0x0E.

AIC - ASCII Integer to

String

Dest

AIC AIC

Integer to String

Source N7:0

ST14:1


Table 20.5 Execution Time for the AIC Instruction

Controller Data Size When Instruction Is:

True False

MicroLogix 1200 word 29.3

µ s + 5.2

µ s/character 0.0

µ s long word 82.0

µ s 0.0

µ s

MicroLogix 1500 Series B, FRN 4 or later word 25

µ s + 4.3

µ s/character long word 68.7

µ s

0.0

0.0

µ

µ s s

The AIC instruction converts an integer or long word value (source) to an

ASCII string (destination). The source can be a constant or an address.

The source data range is from -2,147,483,648 to 2,147,483,647.




Table 20.6 AIC Instruction Valid Addressing Modes and File Types



Address

Mode

Parameter

Address

Level

Source

Destination

• • • • •

•

• • •

•

• •

•

AWA - ASCII Write with

Append

ASCII Write Append

Channel

Source

Control

String Length

Characters Sent

Error

ST14:3

0

R6:2

12

0

0

EN

DN

ER


Table 20.7 Execution Time for the AWA Instruction

Controller

MicroLogix 1200


When Instruction Is:

True False

268

µ s + 12

µ s/character 14.1

µ s

236

µ s + 10.6

µ s/character 12.5

µ s

Use the AWA instruction to write characters from a source string to an external device. This instruction adds the two appended characters that you configure on the Channel Configuration screen. The default is a carriage return and line feed appended to the end of the string.

NOTE

You configure append characters via the Channel

Configuration screen. The default append characters are carriage return and line feed.

Programming AWA Instructions

When programming ASCII output instructions, always precede the ASCII instruction with conditional logic that detects when new data needs to be sent or, send data on a time interval. If sent on a time interval, use an interval of 0.5 second or greater. Do not continuously generate streams of

ASCII data out of a communications port.

IMPORTANT

If ASCII write instructions execute continuously, you may not be able to re-establish communications with RSLogix

500 when the controller is placed into the RUN mode.

This instruction will execute on either a false or true rung. However, if you want to repeat this instruction, the rung must go from false-to-true.




When using this instruction you can also perform in-line indirection. See

page 20-29 for more information.



•



•

Source is the string element you want to write.

•

Control is the control data file. See page 20-6.

•

String Length (.LEN) is the number of characters you want to write from the source string (0 to 82). If you enter a 0, the entire string is written. This is word 1 in the control data file.

•

Characters Sent (.POS) is the number of characters that the controller sends to an external device. This is word 2 in the control data file.

Characters Sent (.POS) is updated after all characters have been transmitted.

The valid range for .POS is from 0 to 84. The number of characters sent to the destination may be smaller or greater than the specified

String Length (.LEN) as described below:

– Characters Sent (.POS) may be smaller than String Length (.LEN) if the length of the string sent is less than what was specified in the

String Length (.LEN) field.

– Characters Sent (.POS) can be greater than the String Length

(.LEN) if the appended characters or inserted values from in-line indirection are used. If the String Length (.LEN) is greater than 82, the string written to the destination is truncated to 82 characters plus the number of append characters (this number could be 82,

83, or 84 depending on how many append characters are used).

•

Error displays the hexadecimal error code that indicates why the ER

bit was set in the control data file. See page 20-30 for error code

descriptions.


Table 20.8 AWA Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Source

Control •

•


•

•

•

•

•

•


Example

[

I:1

[

10

If input slot 1, bit 10 is set, read 25 characters from

ST37:42 and write it to the display device. Then write a carriage return and line feed (default).

AWA

ASCII WRITE APPEND

Channel

Source

Control

String Length

Characters Sent

Error

0

ST37:42

R6:23

25

0

00

EN

DN

ER

In this example, when the rung goes from false-to-true, the control element Enable (EN) bit is set. When the instruction is placed in the ASCII queue, the Queue bit (EU) is set. The Running bit (RN) is set when the instruction is executing. The DN bit is set on completion of the instruction.

The controller sends 25 characters from the start of string ST37:42 to the display device and then sends user-configured append characters. The

Done bit (DN) is set and a value of 27 is present in .POS word of the

ASCII control data file.

When an error is detected, the error code is written to the Error Code Byte

and the Error Bit (ER) is set. See ASCII Instruction Error Codes on page 20-30 for a list of the error codes and recommended action to take.

NOTE

For information on the timing of this instruction, see the

timing diagram on page 20-28.

AWT - ASCII Write

ASCII Write

Channel

Source

Control

String Length

Characters Sent

Error

ST14:4

0

R6:1

40

0

0

EN

DN

ER


Table 20.9 Execution Time for the AWT Instruction


True False

MicroLogix 1200 268

µ s + 12

µ s/character 14.1

µ s

MicroLogix 1500 Series B, FRN 4 or later 237

µ s + 10.6

µ s/character 12.8

µ s

Use the AWT instruction to write characters from a source string to an external device.

Programming AWT Instructions

When programming ASCII output instructions, always precede the ASCII instruction with conditional logic that either detects when new data needs


20-12 ASCII Instructions to be sent or, send data on a time interval. If sent on a time interval, use an interval of 0.5 second or greater.

IMPORTANT

Do not continuously generate streams of ASCII data out of a communications port. If ASCII write instructions execute continuously, you may not be able to re-establish communications with RSLogix 500 when the controller is placed into the RUN mode.

This instruction executes on a true rung. Once started, if the rung goes false, the instruction continues to completion. If you want to repeat this instruction, the rung must transition from false-to-true.

When using this instruction you can also perform in-line indirection. See

page 20-29 for more information.



•



•

Source is the string element you want to write.

•


•

String Length (.LEN) is the number of characters you want to write from the source string (0 to 82). If you enter a 0, the entire string is written. This is word 1 in the control data file.

•

Characters Sent (.POS) is the number of characters that the controller sends to an external device. This is word 2 in the control data file.

Characters Sent (.POS) is updated after all characters have been transmitted.

The valid range for .POS is from 0 to 82. The number of characters sent to the destination may be smaller or greater than the specified

String Length (.LEN) as described below:

– Characters Sent (.POS) may be smaller than String Length (.LEN) if the length of the string sent is less than what was specified in the

String Length (.LEN) field.

– Characters Sent (.POS) can be greater than the String Length

(.LEN) if inserted values from in-line indirection are used. If the

String Length (.LEN) is greater than 82, the string written to the destination is truncated to 82 characters.

•



descriptions.




Table 20.10 AWT Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Source

Control •

•


Example

[

I:1

[

10

If input slot 1, bit 10 is set, write 40 characters from

ST37:20 to the display device.

AWT

ASCII WRITE

Channel

Source

Control

String Length

Characters Sent

Error

•

•

•

•

0

ST37:20

R6:23

40

0

0

EN

DN

ER

•

•

In this example, when the rung goes from false-to-true, the control element Enable (EN) bit is set. When the instruction is placed in the ASCII queue, the Queue bit (EU) is set. The Running bit (RN) is set when the instruction is executing. The DN bit is set on completion of the instruction.

Forty characters from string ST37:40 are sent through channel 0. The

Done bit (DN) is set and a value of 40 is present in the POS word of the

ASCII control data file.

When an error is detected, the error code is written to the Error Code Byte

and the Error Bit (ER) is set. See ASCII Instruction Error Codes on page 20-30 for a list of the error codes and recommended action to take.

NOTE





ABL - Test Buffer for Line

Ascii Test For Line

Channel

Control

Characters

Error

R6:0

0

1<

0<

EN

DN

ER


Table 20.11 Execution Time for the ABL Instruction


True False


µ s + 8.6

µ s/character 12.5

µ s


µ s + 7.6

µ s/character 11.4

µ s

The ABL instruction is used to determine the number of characters in the receive buffer of the specified communication channel, up to and including the end-of-line characters (termination). This instruction looks for the two termination characters that you configure via the channel configuration screen. On a false-to-true transition, the controller reports the number of characters in the POS field of the control data file. The channel configuration must be set to ASCII.



•



•


•

Characters are the number of characters in the buffer that the controller finds (0 to 1024). This parameter is read-only and resides in word 2 of the control data file.

•



descriptions.


Table 20.12 ABL Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Control •


•

•

•

•




When the rung goes from false-to-true, the Enable bit (EN) is set. The instruction is put in the ASCII instruction queue, the Queue bit (EU) is set, and program scan continues. The instruction is then executed outside of the program scan. However, if the queue is empty the instruction executes immediately. Upon execution, the Run bit (RN) is set.

The controller determines the number of characters (up to and including the termination characters) and puts this value in the POS field of the control data file. The Done bit (DN) is then set. If a zero appears in the

POS field, no termination characters were found. The Found bit (FD) is set if the POS field is set to a non-zero value.

ACB - Number of

Characters in Buffer

Ascii Chars In Buffer

Channel

Control

Characters

Error

0

R6:1

2<

0<

EN

DN

ER


Table 20.13 Execution Time for the ACB Instruction

Controller




True

103.1

84.2

µ s

False

12.1

11.0

µ s

Use the ACB instruction to determine the number of characters in the buffer. On a false-to-true transition, the controller determines the total number of characters and records it in the POS field of the control data file. The channel configuration must be set to ASCII.



•



•


•

Characters are the number of characters in the buffer that the controller finds (0 to 1024). This parameter is read-only.

•


bit was set in the control data file. See page 20-30 for error

descriptions.




Table 20.14 ACB Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Control •


•

•

•

•


When the rung goes from false-to-true, the Enable bit (EN) is set. When the instruction is placed in the ASCII queue, the Queue bit (EU) is set. The

Running bit (RN) is set when the instruction is executing. The Done bit

(DN) is set on completion of the instruction.

The controller determines the number of characters in the buffer and puts this value in the POS field of the control data file. The Done bit (DN) is then set. If a zero appears in the POS field, no characters were found. The

Found bit (FD) is set when the POS filed is set to a non-zero value

ACI - String to Integer

String to Integer

Source

Dest

ST10:0

N7:0

0<


Table 20.15 Execution Time for the ACI Instruction

Controller

MicroLogix 1200 Series B,

FRN 3 or later

MicroLogix 1500 Series B,

FRN 4 or later

Data Size When Instruction Is:

True False

word 17.6

µ s + 7.2

µ s/character 0.0

µ s long word 24.6

µ s + 11.6

µ s/character 0.0

µ s

14.2

µ s + 6.3

µ s/character 0.0

µ s

Use the ACI instruction to convert a numeric ASCII string to an integer

(word or long word) value.





•

Source - The contents of this location are converted to an integer value.

•

Destination - This is the location which receives the result of the conversion. The data range is from -32,768 to 32,767 if the destination is a word and from -2,147,483,648 to 2,147,483,647 if the destination is a long word.


Table 20.16 ACI Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Source

Destination • • • •

•

•


•

• • •

•


The controller searches the source (file type ST) for the first character between 0 and 9. All numeric characters are extracted until a non-numeric character or the end of the string is reached. Action is taken only if numeric characters are found. The string length is limited to 82 characters.

Commas and signs (

+,

-) are allowed in the string. However, only the minus sign is displayed in the data table.

This instruction sets the following math flags in the controller status file:

Math Flag

S:0/1 Overflow (V)

S:0/2 Zero (Z)

Description

Flag is set if the result is outside of the valid range.

Flag is set if the result is zero.

S:0/3 Sign (S)

S:5/0 Overflow Trap

Flag is set if the result is negative.

Flag is set when the Overflow flag (S:0/1) is set.

S:5/15 ASCII String

Manipulation Error

Flag is set if the Source string exceeds 82 characters.

When S:5/15 is set, the Invalid String Length Error (1F39H) is written to the Major Error Fault Code (S:6).



ACN - String

Concatenate

String Concatenate

Source A ST10:11

Source B

Dest

ST10:12

ST10:10


Table 20.17 Execution Time for the ACN Instruction


True False

MicroLogix 1200 Series B, FRN 3 or later 22.6

µ s + 11.5

µ s/character 0.0

µ s


µ s + 10.2

µ s/character 0.0

µ s

The ACN instruction combines two ASCII strings. The second string is appended to the first and the result stored in the destination.



•

Source A is the first string in the concatenation procedure.

•

Source B is the second string in the concatenation procedure.

•

Destination is where the result of Source A and B is stored.


Table 20.18 ACN Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Source A

Source B

Destination

•

•

•


•

•

•


This instruction executes on a false-to-true rung transition. Source B is appended to Source A and the result is put in the Destination. Only the first 82 characters (0 to 81) are written to the destination. If the string length of Source A, Source B, or Destination is greater than 82, the ASCII

String Manipulation Error bit S:5/15 is set and the Invalid String Length

Error (1F39H) is written to the Major Error Fault Code word (S:6).

•

•

•



AEX - String Extract

String Extract

Source

Index

Number

Dest

ST10:0

1

5

ST10:3


Table 20.19 Execution Time for the AEX Instruction


True False


µ s + 2.9

µ s/character 0.0

µ s


µ s + 2.6

µ s/character 0.0

µ s

The AEX instruction creates a new string by taking a portion of an existing string and storing it in a new string.



•

Source is the existing string. The Source value is not affected by this instruction.

•

Index is the starting position (from 1 to 82) of the string you want to extract. (An index of 1 indicates the left-most character of the string.)

•

Number is the number of characters (from 1 to 82) you want to extract, starting at the indexed position. If the Index plus the Number is greater than the total characters in the source string, the Destination string will be the characters from the Index to the end of the Source string.

•

Destination is the string element (ST) where you want the extracted string stored.


Table 20.20 AEX Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Source

Index

Number

Destination

• •

• •

• • •

• • •

•

•


•

•

•

•

•

•

•

•




This instruction executes on a true rung.

The following conditions cause the controller to set the ASCII String

Manipulation Error bit (S:5/15):

•

Source string length is less than 1 or greater than 82

•

Index value is less than 1 or greater than 82

•

Number value is less than 1 or greater than 82

•

Index value greater than the length of the Source string

The Destination string is not changed in any of the above error conditions. When the ASCII String Manipulation Error bit (S:5/15) is set, the Invalid String Length Error (1F39H) is written to the Major Error Fault

Code word (S:6).

AHL - ASCII Handshake

Lines

Ascii Handshake Lines

Channel

AND Mask

OR Mask

Control

Channel Status

Error

0002h

0000h

R6:2

0

0000h<

0<

EN

DN

ER


Table 20.21 Execution Time for the AHL Instruction

Controller




True

109.4

µ s

89.3

µ s

False

11.9

µ s

10.8

µ s

The AHL instruction is used to set or reset the RS-232 Request to Send

(RTS) handshake control line for a modem. The controller uses the two masks to determine whether to set or reset the RTS control line, or leave it unchanged. The channel configuration must be set to ASCII.

NOTE

Make sure the automatic modem control used by the port does not conflict with this instruction.



•


1764-LRP only, you can select either Channel 0 or Channel 1.)



•

AND Mask is the mask used to reset the RTS control line. Bit 1 corresponds to the RTS control line. A value of “1” in the AND mask resets the RTS control line; a value of “0” leaves the line unchanged.

The valid data range for the mask is from 0000 to FFFF hexadecimal.

•

OR Mask is the mask used to set the RTS control line. Bit 1 corresponds to the RTS control line. A value of “1” in the OR mask sets the RTS control line; a value of “0” leaves the line unchanged. The valid data range for the mask is from 0000 to FFFF hexadecimal.

•


•

Channel Status displays the current status (0000 to 001F) of the handshake lines for the specified channel. This status is read-only and resides in the .POS field in the control data file. The following shows how to determine the channel status value. In this example, the value is 001F.

Channel

Status Bit

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Handshake

Control Line

Setting reserved --

DCD

0 0 0 0 0 0 0 0 0 0 0 1 1

(1)

-RTS CTS

1 1 1

F Channel

Status

0 0 1

Word 2 of the Control Element = 001F

(1) The DCD handshake line is only supported on Channel 1.

•



descriptions.


Table 20.22 AHL Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

AND Mask

OR Mask

Control

• •

• •

• • •

• • •

•


•

• •

• •

•


This instruction executes on either a false or true rung. However a false-to-true rung transition is required to set the EN bit to repeat the instruction.

•

•

•

•



ARD - ASCII Read

Characters

ASCII Read

Channel

Dest

Control

String Length

Characters Read

Error

ST10:4

0

R6:3

10<

0<

0<

EN

DN

ER


Table 20.23 Execution Time for the ARD Instruction


True False


µ s + 49.7

µ s/character 11.8

µ s


µ s + 44

µ s/character 10.7

µ s

Use the ARD instruction to read characters from the buffer and store them in a string. To repeat the operation, the rung must go from false-to-true.



•



•

Destination is the string element where you want the characters stored.

•


•

String Length (LEN) is the number of characters you want to read from the buffer. The maximum is 82 characters. If you specify a length larger than 82, only the first 82 characters will be read. If you specify 0 characters, LEN defaults to 82. This is word 1 in the control data file.

•

Characters Read (POS) is the number of characters that the controller moved from the buffer to the string (0 to 82). This field is updated during the execution of the instruction and is read-only. This is word 2 in the control data file.

•



descriptions.


Table 20.24 ARD Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Destination

Control •

•


•

•

•

•

•

•




When the rung goes from false-to-true, the Enable bit (EN) is set. When the instruction is placed in the ASCII queue, the Queue bit (EU) is set. The

Running bit (RN) is set when the instruction is executing. The DN bit is set on completion of the instruction.

Once the requested number of characters are in the buffer, the characters are moved to the destination string. The number of characters moved is put in the POS field of the control data file. The number in the POS field is continuously updated and the Done bit (DN) is not set until all of the characters are read.

NOTE



ARL - ASCII Read Line

ASCII Read Line

Channel

Dest

Control

String Length

Characters Read

Error

0

ST10:5

R6:4

15<

0<

0<

EN

DN

ER


Table 20.25 Execution Time for the ARL Instruction


True False


µ s + 50.1

µ s/character 11.7

µ s


µ s + 44.3

µ s/character 10.6

µ s

Use the ARL instruction to read characters from the buffer, up to and including the Termination characters, and store them in a string. The

Termination characters are specified via the Channel Configuration screen.



•



•

Destination is the string element where you want the string stored.

•


•

String Length (LEN) is the number of characters you want to read from the buffer. The maximum is 82 characters. If you specify a length larger than 82, only the first 82 characters are read and moved to the destination. (A length of “0” defaults to 82.) This is word 1 in the control data file.



•

Characters Read (POS) is the number of characters that the controller moved from the buffer to the string (0 to 82). This field is read-only and resides in word 2 of the control data file.

•



descriptions.


Table 20.26 ARL Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Channel

Destination

Control •

•


•

•

•

•

•

•


When the rung goes from false-to-true, the control element Enable (EN) bit is set. When the instruction is placed in the ASCII queue, the Queue bit (EU) is set. The Running bit (RN) is set when the instruction is executing. The DN bit is set on completion of the instruction.

Once the requested number of characters are in the buffer, all characters

(including the Termination characters) are moved to the destination string.

The number of characters moved is stored in the POS word of the control data file. The number in the Characters Read field is continuously updated and the Done bit (DN) is not set until all of the characters have been read.

Exception: If the controller finds termination characters before done reading, the Done bit (DN) is set and the number of characters found is stored in the POS word of the control data file.

NOTE





ASC - String Search

String Search

Source

Index

String Search

Result

ST10:6

ST10:7

5

N7:1

0<


Table 20.27 Execution Time for the ASC Instruction


True False


µ s + 4.0

µ s/matching character 0.0

µ s


µ s + 3.5


µ s

Use the ASC instruction to search an existing string for an occurrence of the source string. This instruction executes on a true rung.



•

Source is the address of the string you want to find.

•

Index is the starting position (from 1 to 82) within the search string.

(An index of 1 indicates the left-most character of the string.)

•

Search is the address of the string you want to examine.

•

Result is the location (from 1 to 82) that the controller uses to store the position in the Search string where the Source string begins. If no match is found, result is set equal to zero.


Table 20.28 ASC Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Source

Index

Search

Result

• •

• •

• • •

• • •

•

•


• •

•

•

•

•

•

•

•



Example

I:1

10

If input slot 1, bit 10 is set, search the string in ST52:80 starting at the 36th character, for the string found in ST38:40. In this example, the position result is stored in N10:0.

String Search

Source

Index

String Search

Result

ST38:40

35

ST52:80

N10:0

Error Conditions

The following conditions cause the controller to set the ASCII Error bit

(S:5/15).

•

Source string length is less than 1 or greater than 82.

•

Index value is less than 1 or greater than 82.

•

Index value is greater than Source string length.

The destination is not changed in any of the above conditions. When the

ASCII String Manipulation Error bit (S:5/15) is set, the Invalid String

Length Error (1F39H) is written to the Major Error Fault Code word (S:6).

ASR - ASCII String

Compare

ASCII String Compare

Source A

Source B

ST10:8

ST10:9


Table 20.29 Execution Time for the ASR Instruction


True False


µ s + 4.0


µ s


µ s + 3.5


µ s

Use the ASR instruction to compare two ASCII strings. The controller looks for a match in length and upper/lower case characters. If two strings are identical, the rung is true; if there are any differences, the rung is false.





•

Source A is the location of the first string used for comparison.

•

Source B is the location of the second string used for comparison.


Table 20.30 ASR Instruction Valid Addressing Modes and File Types


Data Files

(1)

Function Files

Address

Mode

Parameter

Address

Level

Source A

Source B

•

•


•

•

•

•


If the string length of Source A or Source B exceeds 82 characters, the

ASCII String Manipulation Error bit (S:5/15) is set and the rung goes false.



Timing Diagram for ARD,

ARL, AWA, and AWT

Instructions

Rung Condition

ON

OFF

Enable Bit (EN)

ON

OFF

Queue Bit (EU)

ON

OFF

Running Bit (RN)

ON

OFF

Done Bit

Error Bit

(DN or ER)

ON

OFF

1 2 6 3 4 5 1 5

1 - rung goes true

2 - instruction successfully queued

3 - instruction execution complete

4 - instruction scanned for the first time after execution is complete

5 - rung goes false

6 - instruction execution starts

2 6 3 4



Using In-line Indirection

This allows you to insert integer and long word values into ASCII strings.

The Running bit (RN) must be set before the string value can be used.

The following conditions apply to performing in-line indirection:

•

All valid integer (N) and long word (L) files can be used.

Valid range is from 3 to 255.

•

File types are not case sensitive and can include either a colon (:) or semicolon (;)

•

Positive value symbol (+) and leading zeros are not printed. Negative values (-) are printed with a leading minus sign. Commas are not inserted where they would normally appear in numbers greater than one thousand.

Examples

For the following examples:

N7:0 = 25

N7:1 = -37

L8:0 = 508000

L8:1 = 5

.

Valid in-line direction:

Input: Flow rate is currently [N7:0] liters per minute and contains [L8:0] particles per liter contaminants.

Output: Flow rate is currently 25 liters per minute and contains 508000 particles per liter contaminants.

Input: Current position is [N7:1] at a speed of [L8:1] RPM.

Output: Current position is -37 at a speed of 5 RPM.

Invalid in-line indirection:

Input: Current position is [N5:1] at a speed of [L8:1] RPM.

Output: Current position is [N5:1] at a speed of 5 RPM.

NOTE

Truncation occurs in the output string if the indirection causes the output to exceed 82 characters. The appended characters are always applied to the output.



ASCII Instruction Error

Codes

The following error codes indicate why the Error bit (ER) is set in the control data file.

Error Code decimal hexadecimal

0 0x00

3 0x03

5

7

8

9

10

11

12

13

14

15

0x05

0x07

0x08

0x09

0x0A

0x0B

0x0C

0x0D

0x0E

0x0F

Description

No error. The instruction completed successfully.

Recommended Action

None Required.

The transmission cannot be completed because the

CTS signal was lost.

Check the modem and modem connections.

While attempting to perform an ASCII transmission, a conflict with the configured communications protocol was detected.

Reconfigure the channel and retry operation.

The instruction cannot be executed because the communications channel has been shut down via the channel configuration menu.


The instruction cannot be executed because another

ASCII transmission is already in progress.

Resend the transmission.

Type of ASCII communications operation requested is not supported by the current channel configuration.


None required.

The unload bit (UL) is set, stopping instruction execution.

The requested number of characters for the ASCII read was too large or negative.

Enter a valid string length and retry operation.

The length of the Source string is invalid (either a negative number or a number greater than 82).

The requested length in the Control field is invalid

(either a negative number or a number greater than

82).

Execution of an ACL instruction caused this instruction to abort.

Enter a valid string length and retry operation.

Enter a valid length and retry operation.

None required.

Communications channel configuration was changed while instruction was in progress.

None required.



ASCII Character Set

The table below lists the decimal, hexadecimal, octal, and ASCII conversions.

Table 20.31 Standard ASCII Character Set

Column 1 Column 2 Column 3 Column 4

CtrlDEC HEX OCT ASC DEC HEX OCT ASC DEC HEX OCT ASC DEC HEX OCT ASC

^T

Û

^V

^W

^X

^Y

^N

Ô

^P

^Q

^R

^S

^Z

^[

^\

^]

^^

^_

^H

Î

^J

^K

^L

^M

^@

Â

^B

^C

^D

Ê

^F

^G

20

21

22

23

24

25

14

15

16

17

18

19

26

27

28

29

30

31

08

09

10

11

12

13

00

01

02

03

04

05

06

07

14

15

16

17

18

19

0E

0F

10

11

12

13

1A

1B

1C

1D

1E

1F

08

09

0A

0B

0C

0D

00

01

02

03

04

05

06

07

024

025

026

027

030

031

016

017

020

021

022

023

032

033

034

035

036

037

010

011

012

013

014

015

000

001

002

003

004

005

006

007

NUL

SOH

STX

ETX

EOT

ENQ

ACK

BEL

BS

HT

LF

VT

FF

CR

SO

SI

DLE

DC1

DC2

DC3

DC4

NAK

SYN

ETB

CAN

EM

SUB

ESC

FS

GS

RS

US

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

20

21

22

23

24

25

26

27

28

29

2A

2B

2C

2D

2E

2F

30

31

32

33

34

35

36

37

38

39

3A

3B

3C

3D

3E

3F

040

041

042

043

044

045

046

047

050

051

052

053

054

055

056

057

060

061

062

063

064

065

066

067

070

071

072

073

074

075

076

077

;

:

/

.

-

,

)

(

'

!

SP

“

#

$

%

&

*

+

0

1

2

3

4

5

6

7

8

9

<

=

>

?

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

40

41

42

43

44

45

46

47

48

49

4A

4B

4C

4D

4E

4F

50

51

52

53

54

55

56

57

58

59

5A

5B

5C

5D

5E

5F

100

101

102

103

104

105

106

107

110

111

112

113

114

115

116

117

120

121

122

123

124

125

126

127

130

131

132

133

134

135

136

137

]

\

[

I

@

A

B

C

D

E

F

G

H

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

^

_ t u r s p q n o j k l m g i h

}

|

{ z x y v w

~

DEL f d e b c

\ a

120

121

122

123

124

125

126

127

112

113

114

115

116

117

118

119

104

105

106

107

108

109

110

111

96

97

98

99

100

101

102

103

7C

7D

7E

7F

78

79

7A

7B

74

75

76

77

70

71

72

73

6C

6D

6E

6F

68

69

6A

6B

64

65

66

67

60

61

62

63

170

171

172

173

174

175

176

177

160

161

162

163

164

165

166

167

150

151

152

153

154

155

156

157

140

141

142

143

144

145

146

147

The standard ASCII character set includes values up to 127 decimal

(7F hex). The MicroLogix 1200 and 1500 Controllers also support an extended character set (decimal 128 to 255). However, the extended character set may display different characters depending on the platform you are using.

Decimal values 0 through 31 are also assigned Ctrl- codes.




Chapter

21

Communications Instructions

This chapter contains information about the Message (MSG) and Service

Communications (SVC), communication instructions. This chapter provides information on:

• how messaging works

• what the instructions look like

• how to configure and use the instructions

• examples and timing diagrams

The communication instructions read or write data to another station.


MSG Transfer data from one device to another.

SVC

Page

21-3

Interrupt the program scan to execute the service communications part of the operating cycle. The scan then resumes at the instruction following the SVC instruction.

21-26

1

Messaging Overview

The communication architecture is comprised of three primary components:

•

Ladder Scan

•

Communications Buffers

•

Communication Queue

These three components determine when a message is transmitted by the controller. For a message to transmit, it must be scanned on a true rung of logic. When scanned, the message and the data defined within the message (if it is a write message) are placed in a communication buffer.

The controller continues to scan the remaining user program. The message is processed and sent out of the controller via the communications port after the ladder logic completes, during the Service

Communications part of the operating cycle, unless an SVC is executed.

If a second message instruction is processed before the first message completes, the second message and its data are placed in one of the three remaining communication buffers. This process repeats whenever a message instruction is processed, until all four buffers are in use.

When a buffer is available, the message and its associated data are placed in the buffer immediately. If all four buffers for the channel are full when the next (fifth) message is processed, the message request, not the data, is placed in the channel’s communications queue. The queue is a message


21-2 Communications Instructions storage area that keeps track of messages that have not been allocated a buffer. The queue operates as a first-in first-out (FIFO) storage area. The first message request stored in the queue is the message that is allocated a buffer as soon as a buffer becomes available. The queue can accommodate all MSG instructions in a ladder program.

When a message request in a buffer is completed, the buffer is released back to the system. If a message is in the queue, that message is then allocated a buffer. At that time, the data associated with the message is read from within the controller.

NOTE

If a message instruction was in the queue, the data that is actually sent out of the controller may be different than what was present when the message instruction was first processed.

The buffer and queue mechanisms are completely automatic. Buffers are allocated and released as the need arises, and message queuing occurs if buffers are full.

The controller initiates read and write messages through available communication channels when configured for the following protocols:

•

DH-485

•

DF1 Full-Duplex

•


For a description of valid communication protocols, see Protocol

Configuration on pag eE-1.


Communications Instructions 21-3

MSG - Message

Read/Write Message

MSG File MG9:0

Setup Screen

EN

DN

ER


Table 21.1 Execution Time for the MSG Instruction

Controller Rung Condition When Rung Is:

True

MicroLogix 1200 Steady State True 20.0

µ s

False-to-True Transition for Reads 230.0

µ s

False-to-True Transition for Writes 264

µ s + 1.6

µ s per word

MicroLogix 1500 Steady State True 17.0

µ s

False-to-True Transition for Reads 198.0

µ s

False-to-True Transition for Writes 226

µ s + 1.4

µ s per word

False

6.0

µ s

6.0

µ s

Any preceding logic on the message rung must be solved true before the message instruction can be processed. The example below shows a message instruction.

If B3/0 is on (1), the MSG rung is true, and MG11:0 is not already processing a message; then MG11:0 is processed. If one of the four buffers is available, the message and its associated data are processed immediately.

NOTE

How quickly the message is actually sent to the destination device depends on a number of issues, including the selected channel’s communication protocol, the baud rate of the communications port, the number of retries needed (if any), and the destination device's readiness to receive the message.


21-4 Communications Instructions

The Message File

The MSG instruction built into the controller uses a MG data file to process the message instruction. The MG data file, shown at left, is accessed using the MG prefix. Each message instruction utilizes an element within a MG data file. For example, MG11:0 is the first element in message data file 11.

Message File Sub-Elements

Each MSG instruction must use a unique Element in a MSG File. The MSG element for each MSG instruction holds all of the parameters and status information for that particular MSG instruction.

Each MSG File Element consists of Sub-Elements 0 through 24 as shown in the following table.

Message File Element

Sub-

Element

6

7

8

4

5

0 to 2

3

8

9

10

11

12

16

17

18

13

14

15

Name Description

Reserved bits 07-00: CMD code, bits 15-08: FNC code

Reserved

MG11:0.RBL

Remote Bridge Link ID

MG11:0.LBN

Local Bridge Node Address

MG11:0.RBN

Remote Bridge Node Address

MG11:0.CHN

Channel - 0 (channel 0)

Always 0 for MicroLogix 1200 Controllers and MicroLogix 1500

1764-LSP Processors

MG11:0.CHN

Channel - 0 (channel 0) or 1 (channel 1)

MicroLogix 1500 1764-LRP Processors

MG11:0.NOD Target Node Number

MG11:0.MTO Message timeout setting or preset in seconds

Reserved

Target Location information (See tables on page 21-5 for options)

MG11:0.TFN

MG11:0.ELE

Parameter Size User Program

Access

(1)

derived

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Control bits (See Control Bits table on page 21-5 for details)

N

Status bits and Range parameter (See table on page 21-6 for details)

Mixed

MG11:0.ERR

Error code (See Error Codes on page 21-21)

N

Word read only

Word read only

Word read only

Word read only

Word read only

Word read only

Word read only

Word

Word read/write read/write

Word read/write

Word read only

Word read only

Word read/write

Word read/write

Word read only

16-bits read/write

16-bits read only

Word read only

19

20

21

Time since message started in seconds

Reserved

Internal message start time in seconds

N Word read only

Word read only

Word read only

22 to 24 Reserved

N

N Word read only

(1) User access refers to user program access (MSG File word or bit used as an operand for an instruction in a ladder program) or access via Comms while in any mode other than download (via Programming Software or Memory Module).



The Target file information contained in Sub-Elements 12 through 15 of the MSG File Element depend upon the message type, as shown in the tables below.

12

13

14

15

Message File Target Location Information

Target Device = 485 CIF

Sub-

Element

Name Description

Reserved

MG11:0.TFN

Target File Number

MG11:0.ELE

Offset in elements into CIF Y

Reserved Y

Y

Y


Access

Word read only

Word read/write

Word read/write

Word read only

Message File Target Location Information

Target Device = 500CPU or PLC 5

Sub-

Element

12

13

14

Address Description

Target File Type

MG11:0.TFN Target File Number (1) Y

MG11:0.ELE Target File Element Number for B,

S, N, T, C, R, L, ST and RTC

(2) files; or Target File Slot Number for O and I files.

Y


Access

Y Word read only

Word read/write

Word read/write

15 Target File Element Number for O and I files.

Y

Set to zero for any file other than

O or I.

Word read only

(1) The file number for RTC function files is set to 0 by the programming software.

(2) RTC and ST are only permitted in the MSG instruction for MicroLogix 1200 and 1500 Series B Controllers.

The Control Bits, Sub-Element 16, of the MSG File Element are defined below:

Message File Sub-Element 16 - Control Bits

Bit Address Description Parameter Size User Program

Access

N bit read/write 15 MG11:0.0/EN Enable

1=MSG enabled

0=MSG not enabled

9 to

14

Reserved

8 MG11:0.0/TO Time Out

1=MSG time out by user

0=no user MSG time out

0 to

7

Reserved

N

N

N bit read/write bit read/write bit read/write



The Status Bits, Sub-Element 17, of the MSG File Element are defined below.

Message File Sub-Element 17 - Status bits

Bit Address Description

N

N

Parameter Size User

Program

Access

bit bit read only read only

15 Reserved

14 MG11:0.0/ST Start:

1 = MSG transmitted and acknowledged by target device

0 = MSG has not been received by target

13 MG11:0.0/DN Done

1 = MSG completed successfully

0 = MSG not complete

12 MG11:0.0/ER Error

1 = error detected

0 = no error detected

11 Reserved

10 MG11:0.0/EW Enabled and Waiting:

1=MSG Enabled and Waiting

0=MSG not Enabled and Waiting

1 to

9

Reserved

0 MG11:0.0/R Range 1=Local, 0=Remote

N

N

N

N

N

Y bit read only bit read only bit read only bit read only bit read only bit read only



Local Messages

The controller is capable of communicating using local or remote messages. With a local message, all devices are accessible without a separate device acting as a bridge. Different types of electrical interfaces may be required to connect to the network, but the network is still classified as a local network. Remote messages use a remote network, where devices are accessible only by passing or routing through a device

to another network. Remote networks are discussed on page 21-16.

Local Networks

The following three examples represent different types of local networks.

Example 1 - Local DH-485 Network with AIC+ (1761-NET-AIC) Interface

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

A-B PanelView

SLC 5/04

PanelView 550

DH-485 Network

AIC+

TX

TERM

COM

SHLD

CHS GND

TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TX

TERM

COM

SHLD

CHS GND

TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

Personal

Computer

MicroLogix 1000 MicroLogix 1200 MicroLogix 1500

Example 2 - Local DeviceNet Network with DeviceNet Interface (1761-NET-DNI)

DNI SLC 5/03 with 1747-SDN DNI PanelView 550

A-B PanelView

DANGER DANGER

DeviceNet Network

DNI

DANGER DANGER

DNI

DANGER

Master

DNI

DANGER

DNI

Personal

Computer

MicroLogix 1000 MicroLogix 1200 MicroLogix 1500



Rockwell Software RSLinx 2.0 (or higher), SLC 5/03, SLC 5/04, and

SLC 5/05, or PLC-5 processors configured for DF1 Half-Duplex

Master.

Example 3 - Local DF1 Half-Duplex Network

RS-232

(DF1 Half-Duplex Protocol)

Modem

MicroLogix

1000 (Slave)

MicroLogix

1200 (Slave)

MicroLogix

1500 (Slave)

NOTE

SLC 5/04 (Slave) SLC 5/03 with 1747-KE

Interface Module (Slave)

It is recommended that isolation (1761-NET-AIC) be provided between the controller and the modem.


Configuring a Local

Message


Message Setup Screen

The rung below shows a MSG instruction preceded by conditional logic.

Access the message setup screen by double-clicking Setup Screen.

0000

B3:0

0

Read/Write Message

MSG File MG11:0

Setup Screen

EN

DN

ER

The RSLogix Message Setup Screen is shown below. This screen is used to setup “This Controller”, “Target Device”, and “Control Bits”. Descriptions of each of the elements follow.



“This Controller” Parameters

Communication Command

The controller supports six different types of communications commands.

If the target device supports any of these command types, the controller should be capable of exchanging data with the device. Supported commands include:

Table 21.2 Communication Command Types

Communication

Command

500CPU Read

Description

500CPU Write

485CIF Read

485CIF Write

PLC5 Read

PLC5 Write

(1)

(1)

The target device is compatible with and supports the

SLC 500 command set (all MicroLogix controllers).


SLC 500 command set (all MicroLogix controllers).


485CIF (PLC2).


485CIF (PLC2).


PLC5 command set.


PLC5 command set.

(1) See Important note below.

Used For

reading data sending data reading data sending data reading data sending data

IMPORTANT

The Common Interface File (CIF) in the MicroLogix 1200,

1500, and SLC 500 processors is File 9. The CIF in the

MicroLogix 1000 controller is Integer File 7.

Table 21.3 Communication Commands

Command

0x01

0x08

0x0F

Function

0x00

0x01

0x67

0x68

0xA1

0xA2

0xA3

0xA7

0xA9

0xAA

0xAB

0xAF

Description

unprotected read unprotected write word range write word range read

PLC typed write

PLC typed read logical read with 2 address fields logical read with 3 address fields scattered read file read logical write with 2 address fields logical write with 3 address fields logical write with 4 address fields file write



Data Table Address

This variable defines the starting address in the local controller. Valid file types for the Data Table Address are shown below:

Message Read

Bit (B)

Timer (T)

Counter (C)

Control (R)

Integer (N)

Long Word (L)

Message Write

Output (O)

Input (I)

Bit (B)

Timer (T)

Counter (C)

Control (R)

Integer (N)

Long Word (L)

String (ST)

(1)(2)

Real-Time Clock (RTC)

(1)(3)

(1) Applies to MicroLogix 1200 Series B and later, and 1500 Series B and later only.

(2) 485CIF write ST-to-485CIF only.

(3) 500CPU write RTC-to-Integer or RTC-to-RTC only.

Size in Elements

This variable defines the amount of data (in elements) to exchange with the target device.

The maximum amount of data that can be transferred via a MSG instruction is 103 words (206 bytes) and is determined by the destination data type. The destination data type is defined by the type of message: read or write.

•

For Read Messages: When a read message is used, the destination file is the data file in the local or originating processor.

NOTE

Input, output, string, and RTC file types are not valid for read messages.

•

For Write Messages: When a write message is used, the destination file is the data file in the target processor.

The maximum number of elements that can be transmitted or received are shown in the following table. You cannot cross file types when sending messages. For example, you cannot read a timer into an integer file and you cannot write counters to a timer file. The only exceptions to this rule are that:

• long integer data can be read from or written to bit or integer files, and

•

RTC files can be written to integer files (MicroLogix 1200 Series B and

later, and 1500 Series B and later only).



NOTE

The table below is not intended to illustrate file compatibility, only the maximum number of elements that can be exchanged in each case.

Message Type File Type

485CIF

500CPU

PLC5

O, I, B, N

L

T, C, R

ST

L

O, I, B, N

T, C, R

RTC

O, I, B, N

L

T

Element Size

1-word

2-word

3-word

42-word

1-word

2-word

3-word

8-word

1-word

2-word

5-word

Maximum Number of Elements per Message

103

51

34

2 (write only)

103

51

34

1 (write only)

103

51

20

Channel

This variable defines the communication channel that is used to transmit the message request. For controllers with only one communication channel, this value is factory-set to channel 0 and cannot be changed. For controllers with 2 channels (1764-LRP processor installed), the channel can be 0 or 1.

“Target Device” Parameters

Message Timeout

This value defines how long, in seconds, the message instruction has to complete its operation once it has started. Timing begins when the false-to-true rung transition occurs, enabling the message. If the timeout period expires, the message errors out. The default value is 5 seconds.

The maximum timeout value is 255 seconds.

If the message timeout is set to zero, the message instruction will never timeout. Set the Time Out bit (TO = 1) to flush a message instruction from its buffer if the destination device does not respond to the communications request.



Data Table Address/Offset

This variable defines the starting address in the target controller. The data table address is used for a 500CPU and PLC5 type messages. A valid address is any valid, configured data file within the target device whose file type is recognized by the controller. Valid combinations are shown below:

Message Type

500CPU and PLC5

T

C

Local File Type

O, I, B, N, L

T

C

Target File Type

O, I, S, B, N, L

R

RTC

(1)

R

N, RTC

(1) 500CPU write RTC-to-Integer or RTC-to-RTC only. Applies to MicroLogix 1200 Series B and later, and 1500 Series B and later only.

The data table offset is used for 485CIF type messages. A valid offset is any value in the range 0 to 255 and indicates the word or byte offset into the target's Common Interface File (CIF). The type of device determines whether it is a word or byte offset. MicroLogix controllers and SLC processors use word offset; PLC-5 uses byte offset.

Local Node Address

This is the destination device's node number if the devices are on a

DH-485 (using 1761-NET-AIC), DeviceNet (using 1761-NET-DNI), or DF1

Half-Duplex network.

NOTE

To initiate a broadcast message on a DH-485 network, set the local node address to -1.

Local/Remote

This variable defines the type of communications that is used. Use local when you need point-to-point communications via DF1 Full-Duplex or network communications such as DH-485 (using 1761-NET-AIC),

DeviceNet (using 1761-NET-DNI), or DF1 Half-Duplex.



“Control Bits” Parameters

Ignore if Timed Out (TO)

Address

MG11:0/TO

Data Format

Binary

Range

On or Off


Control Read / Write

The Timed Out Bit (TO) can be set in your application to remove an active message instruction from processor control. You can create your own timeout routine by monitoring the EW and ST bits to start a timer.

When the timer times out, you can set the TO bit, which removes the message from the system. The controller resets the TO bit the next time the associated MSG rung goes from false to true.

An easier method is to use the message timeout variable described on

page 21-12, because it simplifies the user program. This built-in timeout

control is in effect whenever the message timeout is non-zero. It defaults to 5 seconds, so unless you change it, the internal timeout control is automatically enabled.

When the internal timeout is used and communications are interrupted, the MSG instruction will timeout and error after the set period of time expires. This allows the control program to retry the same message or take other action, if desired.

To disable the internal timeout control, enter zero for the MSG instruction timeout parameter. If communications are interrupted, the processor waits indefinitely for a reply. If an acknowledge (ACK) is received, indicated by the ST bit being set, but the reply is not received, the MSG instruction appears to be locked up, although it is actually waiting for a reply from the target device.

Enable (EN)

Address

MG11:0/EN

Data Format

Binary

Range

On or Off


Control Read / Write

The Enable Bit (EN) is set when rung conditions go true and the MSG is enabled. The MSG is enabled when the command packet is built and put into one of the MSG buffers, or the request is put in the MSG queue. It remains set until the message transmission is completed and the rung goes false. You may clear this bit when either the ER or DN bit is set in order to re-trigger a MSG instruction with true rung conditions on the next scan.

IMPORTANT

Do not set this bit from the control program.



Enabled and Waiting (EW)

Address

MG11:0/EW

Data Format

Binary

Range Type

On or Off Status

User Program Access

Read Only

The Enabled and Waiting Bit (EW) is set after the enable bit is set and the message is in the buffer (not in the queue) and waiting to be sent. The

EW bit is cleared after the message has been sent and the processor receives acknowledgement (ACK) from the target device. This is before the target device has processed the message and sent a reply.

Error (ER)

Address

MG11:0/ER

Data Format

Binary

Range Type

On or Off Status


Read Only

The Error Bit (ER) is set when message transmission has failed. An error code is written to the MSG File. The ER bit and the error code are cleared the next time the associated rung goes from false to true.

Done (DN)

Address

MG11:0/DN

Data Format

Binary

Range Type

On or Off Status


Read Only

The Done Bit (DN) is set when the message is transmitted successfully.

The DN bit is cleared the next time the associated rung goes from false to true.

Start (ST)

Address

MG11:0/ST

Data Format

Binary

Range Type

On or Off Status


Read Only

The Start Bit (ST) is set when the processor receives acknowledgment

(ACK) from the target device. The ST bit is cleared when the DN, ER, or

TO bit is set.



Remote Messages

The controller is also capable of remote or off-link messaging. Remote messaging is the ability to exchange information with a device that is not connected to the local network. This type of connection requires a device on the local network to act as a bridge or gateway to the other network.

Remote Networks

DH-485 and DH+ Networks

The illustration below shows two networks, a DH-485 and a DH+ network. The SLC 5/04 processor at DH-485 node 17 is configured for passthru operation. Devices that are capable of remote messaging and are connected on either network can initiate read or write data exchanges with devices on the other network, based on each device's capabilities. In this example, node 12 on DH-485 is a MicroLogix 1500. The MicroLogix

1500 can respond to remote message requests from nodes 40 or 51 on the

DH+ network and it can initiate a message to any node on the DH+ network.

NOTE

The MicroLogix 1000 can respond to remote message requests, but it cannot initiate them.

NOTE

The MicroLogix 1200 capabilities are the same as the

MicroLogix 1500 in this example.

This functionality is also available on Ethernet by replacing the SLC 5/04 at DH-485 node 17 with an SLC 5/05 processor.

Figure 21.1 DH-485 and DH+ Networks

TERM

TX

COM

SHLD

CHS GND

TX

AIC+

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

A-B PanelView

SLC 5/04

PanelView 550

DH-485 Network

AIC+

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

Node 12

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+ AIC+

Node 17

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

MicroLogix 1000

DH+ Network

Node 51

MicroLogix 1200 MicroLogix 1500

Node 40

SLC 5/04

Node 19

SLC 5/04 PLC-5



DeviceNet and Ethernet Networks

The illustration below shows a DeviceNet network using DeviceNet

Interfaces (1761-NET-DNI) connected to an Ethernet network using an

SLC 5/05. In this configuration, controllers on the DeviceNet network can reply to requests from devices on the Ethernet network, but cannot initiate communications to devices on Ethernet.

Figure 21.2 DeviceNet and Ethernet Networks

DNI

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

DNI

TX

TERM

COM

SHLD

CHS GND

TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

A-B PanelView

SLC 5/03

PanelView 550

DeviceNet Network

TX

TERM

COM

SHLD

CHS GND

TX

DNI

TX PWR

DC SOURCE

CABLE

EXTERNAL

TX

TERM

COM

SHLD

CHS GND

TX

DNI

TX PWR

DC SOURCE

CABLE

EXTERNAL

TX

TERM

COM

SHLD

CHS GND

TX

DNI

TX PWR

DC SOURCE

CABLE

EXTERNAL

DNI

TERM

TX

COM

SHLD

CHS GND

TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

MicroLogix 1000

Ethernet Network

MicroLogix 1200 MicroLogix 1500 SLC 5/05

SLC 5/05 PLC-5E



Configuring a Remote

Message

You configure for remote capability in the RSLogix 500 Message Setup screen.

Example Configuration Screen and Network

The message configuration shown below is for the MicroLogix 1500 at node 12 on the DH-485 network. This message reads five elements of data from the SLC 5/04 (node 51 on the DH+ network) starting at address

N:50:0. The SLC 5/04 at Node 23 of the DH+ network is configured for passthru operation.

NOTE

The MicroLogix 1200 capabilities are the same as the

MicroLogix 1500 in this example.



Figure 21.3 DH-485 and DH+ Example Network

Node 10

DH-485 Network

AIC+

Node 11

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

TERM

TX

COM

SHLD

CHS GND

TX

AIC+

TX PWR

DC SOURCE

CABLE

EXTERNAL

SLC 5/03

Node 5

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

Node 12

TERM

COM

SHLD

CHS GND

TX TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

AIC+

TERM

COM

SHLD

CHS GND

TX TX

AIC+

TX PWR

DC SOURCE

CABLE

EXTERNAL

A-B PanelView

Node 22

AIC+

TX

TERM

COM

SHLD

CHS GND

TX

TX PWR

DC SOURCE

CABLE

EXTERNAL

Node 17

PanelView 550

Link ID = 1

MicroLogix 1000

DH+ Network

MicroLogix 1200

Node 63 octal (51 decimal)

MicroLogix 1500

SLC 5/04



Link ID = 100

SLC 5/04 PLC-5

“This Controller” Parameters

See “Target Device” Parameters on page 21-12.

“Control Bits” Parameters

See “Control Bits” Parameters on page 21-14.

“Target Device” Parameters

Message Timeout

See Message Timeout on page 21-12.

Data Table Address

See Data Table Address/Offset on page 21-13.

Local Bridge Address

This variable defines the bridge address on the local network. In the example, DH-485 node 12 (MicroLogix 1500 on Link ID 1) is writing data to node 51 (SLC 5/04 on Link ID 100). The SLC 5/04 at node 17 is the bridge device.

This variable sends the message to local node 17.



Remote Bridge Address

This variable defines the remote node address of the bridge device. In this example, the remote bridge address is set to zero, because the target device, SLC 5/04 at node 63 (octal) is a remote-capable device. If the target device is remote-capable, the remote bridge address is not required.

If the target device is not remote-capable (SLC 500, SLC 5/01, SLC 5/02, and MicroLogix 1000 Series A, B and C), the remote bridge address is required.

Remote Station Address

This variable is the final destination address of the message instruction. In this example, integer file 50 elements 0 to 4 of the SLC 5/04 on Link ID

100 at node 63 (octal) receives data from the MicroLogix 1500 controller at node 12 on Link ID 1.

Remote Bridge Link ID

This variable is a user-assigned value that defines the remote network as a number. This number must be used by any device initiating remote messaging to that network. In the example, any controller on Link ID 1 sending data to a device on Link ID 100 must use the remote bridge link

ID of the passthru device. In this example, the SLC 5/04 on Link ID1, node 17 is the passthru device.

Passthru Link ID

Set the Passthru Link ID in the General tab on the Channel Configuration screen. The Link ID value is a user-defined number between 1 and

65,535. All devices that can initiate remote messages and are connected to the local network must have the same number for this variable.



MSG Instruction Error

Codes

When the processor detects an error during the transfer of message data, the processor sets the ER bit and enters an error code that you can monitor from your programming software.

D1H

D2H

D3H

D4H

D5H

45H

50H

60H

70H

80H

90H

B0H

C0H

D0H

21H

30H

37H

39H

3AH

40H

12H

13H

15H

16H

17H

18H

07H

08H

09H

0BH

0CH

10H

Error Code Description of Error Condition

02H Target node is busy. NAK No Memory retries by link layer exhausted.

03H

04H

05H

06H

Target node cannot respond because message is too large.

Target node cannot respond because it does not understand the command parameters OR the control block may have been inadvertently modified.

Local processor is off-line (possible duplicate node situation).

Target node cannot respond because requested function is not available.

Target node does not respond.

Target node cannot respond.

Local modem connection has been lost.

Target node does not accept this type of MSG instruction.

Received a master link reset (one possible source is from the DF1 master).

Target node cannot respond because of incorrect command parameters or unsupported command.

Local channel configuration protocol error exists.

Local MSG configuration error in the Remote MSG parameters.

Local channel configuration parameter error exists.

Target or Local Bridge address is higher than the maximum node address.

Local service is not supported.

Broadcast is not supported.

Bad MSG file parameter for building message.

PCCC Description: Remote station host is not there, disconnected, or shutdown.

Message timed out in local processor.

Local communication channel reconfigured while MSG active.

STS in the reply from target is invalid.

PCCC Description: Host could not complete function due to hardware fault.

MSG reply cannot be processed. Either Insufficient data in MSG read reply or bad network address parameter.

Target node is out of memory.

Target node cannot respond because file is protected.

PCCC Description: Processor is in Program Mode.

PCCC Description: Compatibility mode file missing or communication zone problem.

PCCC Description: Remote station cannot buffer command.

PCCC Description: Remote station problem due to download.

PCCC Description: Cannot execute command due to active IPBs.

One of the following:

•

•

•

•

No IP address configured for the network.

Bad command - unsolicited message error.

Bad address - unsolicited message error.

No privilege - unsolicited message error.

Maximum connections used - no connections available.

Invalid internet address or host name.

No such host / Cannot communicate with the name server.

Connection not completed before user–specified timeout.

Connection timed out by the network.



FBH

FCH

FDH

FFH

F7H

F8H

F9H

FAH

F2H

F3H

F4H

F5H

F6H

EEH

EFH

F0H

F1H

E6H

E7H

E8H

E9H

EAH

EBH

ECH

EDH

E1H

E2H

E3H

E4H

E5H

Error Code Description of Error Condition

D7H Connection refused by destination host.

D8H

D9H

DAH

Connection was broken.

Reply not received before user–specified timeout.

No network buffer space available.

PCCC Description: Illegal Address Format, a field has an illegal value.

PCCC Description: Illegal Address format, not enough fields specified.

PCCC Description: Illegal Address format, too many fields specified.

PCCC Description: Illegal Address, symbol not found.

PCCC Description: Illegal Address Format, symbol is 0 or greater than the maximum number of characters support by this device.

PCCC Description: Illegal Address, address does not exist, or does not point to something usable by this command.

Target node cannot respond because length requested is too large.

PCCC Description: Cannot complete request, situation changed (file size, for example) during multi–packet operation.

PCCC Description: Data or file is too large. Memory unavailable.

PCCC Description: Request is too large; transaction size plus word address is too large.

Target node cannot respond because target node denies access.

Target node cannot respond because requested function is currently unavailable.

PCCC Description: Resource is already available; condition already exists.

PCCC Description: Command cannot be executed.

PCCC Description: Overflow; histogram overflow.

PCCC Description: No access.

Local processor detects illegal target file type.

PCCC Description: Invalid parameter; invalid data in search or command block.

PCCC Description: Address reference exists to deleted area.

PCCC Description: Command execution failure for unknown reason; PLC-3 histogram overflow.

PCCC Description: Data conversion error.

PCCC Description: The scanner is not able to communicate with a 1771 rack adapter. This could be due to the scanner not scanning, the selected adapter not being scanned, the adapter not responding, or an invalid request of a “DCM BT (block transfer)”.

PCCC Description: The adapter is not able to communicate with a module.

PCCC Description: The 1771 module response was not valid size, checksum, etc.

PCCC Description: Duplicated Label.

Target node cannot respond because another node is file owner (has sole file access).

Target node cannot respond because another node is program owner (has sole access to all files).

PCCC Description: Disk file is write protected or otherwise inaccessible (off-line only).

PCCC Description: Disk file is being used by another application; update not performed (off-line only).

Local communication channel is shut down.

NOTE

For 1770-6.5.16 DF1 Protocol and Command Set

Reference Manual users: The MSG error code reflects the

STS field of the reply to your MSG instruction.

•

Codes E0 to EF represent EXT STS codes 0 to F.

•

Codes F0 to FC represent EXT STS codes 10 to 1C.



Timing Diagram for the

MSG Instruction

The following section describes the timing diagram for a message instruction.

(1) Rung goes true.

(3) Target node receives packet.

(1)

(2) (3)

(5) Target node processes packet successfully and returns data (read) or acknowledges receipt (write).

(5) (6)

EN

1

0

EW

1

0

ST

1

0

DN

ER

1

0

1

0

TO

1

0

1. If there is room in any of the four active message buffers when the

MSG rung becomes true and the MSG is scanned, the EN and EW bits for this message are set. If this is a MSG write instruction, the source data is transferred to the message buffer at this time.

(Not shown in the diagram.) If the four message buffers are in use, the message request is put in the message queue and only the EN bit is set. The message queue works on a first-in, first-out basis that allows the controller to remember the order in which the message instructions were enabled. When a buffer becomes available, the first message in the queue is placed into the buffer and the EW bit is set

(1).

NOTE

The control program does not have access to the message buffers or the communications queue.

Once the EN bit is set (1), it remains set until the entire message process is complete and either the DN, ER, or TO bit is set (1). The

MSG Timeout period begins timing when the EN bit is set (1). If the timeout period expires before the MSG instruction completes its function, the ER bit is set (1), and an error code (37H) is placed in the

MG File to inform you of the timeout error.



2. At the next end of scan, REF, or SVC instruction, the controller determines if it should examine the communications queue for another instruction. The controller bases its decision on the state of the channel’s Communication Servicing Selection (CSS) and Message

Servicing Selection (MSS) bits, the network communication requests from other nodes, and whether previous message instructions are already in progress. If the controller determines that it should not access the queue, the message instruction remains as it was. Either the

EN and EW bits remain set (1) or only the EN bit is set (1) until the next end of scan, REF, or SVC instruction.

If the controller determines that it has an instruction in the queue, it unloads the communications queue entries into the message buffers until all four message buffers are full. If an invalid message is unloaded from the communications queue, the ER bit in the MG file is set (1), and a code is placed in the MG file to inform you of an error.

When a valid message instruction is loaded into a message buffer, the

EN and EW bits for this message are set (1).

The controller then exits the end of scan, REF, or SVC portion of the scan. The controller’s background communication function sends the messages to the target nodes specified in the message instruction.

Depending on the state of the CSS and MSS bits, you can service up to four active message instructions per channel at any given time.

3. If the target node successfully receives the message, it sends back an acknowledge (ACK). The ACK causes the processor to clear (0) the

EW bit and set (1) the ST bit. The target node has not yet examined the packet to see if it understands your request.

Once the ST bit is set (1), the controller waits for a reply from the target node. The target node is not required to respond within any given time frame.

NOTE

If the Target Node faults or power cycles during the message transaction, you will never receive a reply.

This is why you should use a Message Timeout value in your MSG instruction.



4. Step 4 is not shown in the timing diagram. If you do not receive an

ACK, step 3 does not occur. Instead, either no response or a negative acknowledge (NAK) is received. When this happens, the ST bit remains clear (0).

No response may be caused by:

• the target node is not there

• the message became corrupted in transmission

• the response was corrupted in response transmission

A NAK may be caused by:

• target node is busy

• target node received a corrupt message

• the message is too large

When a NAK occurs, the EW bit is cleared (0), and the ER bit is set

(1), indicating that the message instruction failed.

5. Following the successful receipt of the packet, the target node sends a reply packet. The reply packet contains one of the following responses:

• successful write request.

• successful read request with data

• failure with error code

At the next end of scan, REF, or SVC instruction, following the target node’s reply, the controller examines the message from the target device. If the reply is successful, the DN bit is set (1), and the ST bit is cleared (0). If it is a successful read request, the data is written to the data table. The message instruction function is complete.

If the reply is a failure with an error code, the ER bit is set (1), and the

ST bit is cleared (0). The message instruction function is complete.

6. If the DN or ER bit is set (1) and the MSG rung is false, the EN bit is cleared (0) the next time the message instruction is scanned.

See MSG Instruction Ladder Logic on page 21-28 for examples using the

message instruction.



SVC - Service

Communications

Service Communications

Channel Select 1


Table 21.4 Execution Time for the EQU and NEQ Instructions

Controller

When Rung Is:

(1)

MicroLogix 1200

True False

208

µ s + 1.6

µ s per word 0.0

µ s

166

µ s + 1.4

µ s per word 0.0

µ s MicroLogix 1500 1764-LSP or

1764-LRP with one channel selected

MicroLogix 1500 1764-LRP Processor with both channels selected

327

µ s + 1.4

µ s per word 0.0

µ s

(1) This value for the SVC instruction is for when the communications servicing function is accessing a data file. The time increases when accessing a function file.

Under normal operation the controller processes communications once every time it scans the control program. If you require the communications port to be scanned more often, or if the ladder scan is long, you can add an SVC (Service Communications) instruction to your control program. The SVC instruction is used to improve communications performance/throughput, but also causes the ladder scan to be longer.

Simply place the SVC instruction on a rung within the control program.

When the rung is scanned, the controller services any communications that need to take place. You can place the SVC instruction on a rung without any preceding logic, or you can condition the rung with a

number of communications status bits. The table on page 21-27 shows the

available status file bits.

NOTE

The amount of communications servicing performed is controlled by the Communication Servicing Selection Bit

(CSS) and Message Servicing Selection Bit (MSS) in the

Channel 0 Communication Configuration File.

For best results, place the SVC instruction in the middle of the control program. You may not place an SVC instruction in a Fault, DII, STI, or I/O

Event subroutine.

Channel Select

When using the SVC instruction, you must select the channel to be serviced. The channel select variable is a one-word bit pattern that determines which channel is serviced. Each bit corresponds to a specific channel. For example, bit 0 equals channel 0. When any bit is set (1), the corresponding channel is serviced.



Controller

MicroLogix 1200

MicroLogix 1500 with 1764-LSP Processor 1

Channel Select Setting Channel(s) Serviced

1 0

0

MicroLogix 1500 with 1764-LRP Processor 1

2

3

0

1 both 0 and 1

Communication Status Bits

The following communication status bits allow you to customize or

monitor communications servicing. See General Channel Status Block on page 3-14 for additional status information.

Table 21.5 Communication Status Bits

Address

CS0:4/0

CS0:4/1

CS0:4/2

CS0:4/4

Description

ICP - Incoming Command Pending

MRP - Incoming Message Reply Pending

MCP - Outgoing Message Command Pending

CAB - Communications Active Bit

Application Example

The SVC instruction is used when you want to execute a communication function, such as transmitting a message, prior to the normal service communication portion of the operating scan.

0000

CS0:4

MCP

Service Communications

Channel Select 0001h

You can place this rung after a message write instruction. CS0:4/MCP is set when the message instruction is enabled and put in the communications queue. When CS0:4/MCP is set (1), the SVC instruction is evaluated as true and the program scan is interrupted to execute the service communication’s portion of the operating scan. The scan then resumes at the instruction following the SVC instruction.

The example rung shows a conditional SVC, which is processed only when an outgoing message is in the communications queue.

NOTE

You may program the SVC instruction unconditionally across the rungs. This is the normal programming technique for the SVC instruction.



MSG Instruction Ladder

Logic

Enabling the MSG Instruction for Continuous Operation

The message instruction is enabled during the initial processor program scan and each time the message completes. For example, when the DN or

ER bit is set.

0000

0001

Message Done Bit

MG11:0

DN

Message Error Bit

MG11:0

ER

0002

Read/Write Message

MSG File MG11:0

Setup Screen

EN

DN

ER

Message Enable Bit

MG11:0

U

EN

END

Enabling the MSG Instruction Via User Supplied Input

This is an example of controlling when the message instruction operates.

Input I:1/0 could be any user-supplied bit to control when messages are sent. Whenever I:1/0 is set and message MG11:0 is not enabled, the message instruction on rung 0001 is enabled.

0000

User Supplied

Input

I:1

0

Message

Enable Bit

MG11:0

EN

0001

The message instruction is enabled with each false-to-true transition of bit B3:0/0

B3:0

0

Read/Write Message

MSG File MG11:0

Setup Screen

B3:0

L

0

EN

DN

ER

0002

Message Done Bit

MG11:0

DN

B3:0

U

0

Message Error Bit

MG11:0

ER

0003 END



Local Messaging

Examples

Three examples of local messaging are shown in this section:

•

500CPU message type

•

485CIF message type

•

PLC5 message type

A summary of the message instruction configuration parameters is shown below.

Parameter

This Controller Communication

Command

Data Table Address For a Read, this is the starting address which receives data.

Valid file types are B, T, C, R, N, and L.

For a Write, this is the starting address which is sent to the target device.

Valid file types are O, I, B, T, C, R, N, L, ST

(1)(2)

, and RTC

(1)(3)

.

Size in elements

Channel

Description

Specifies the type of message. Valid types are:

•

•

•

•

•

•

500CPU Read

500CPU Write

485CIF Read

485CIF Write

PLC5 Read

PLC5 Write

Defines the length of the message in elements.

•

•

•

•

•

•

1-word elements; valid size: 1 to 103.

2-word elements; valid size: 1 to 51.

8-word elements; valid size: 1

42-word elements; valid size 1 to 2

Timer (500CPU and 485CIF), Counter, and Control elements; valid size: 1 to 34.

PLC-5 Timer elements; valid size: 1 to 20

Identifies the communication channel. Always Channel 0 (or Channel 1 for MicroLogix 1500

1764-LRP Processor only.)

Target Device Message Timeout

Data Table Address

(500CPU and PLC5 message types)

Defines the amount of time the controller waits for the reply before the message errors. A timeout of 0 seconds means that the controller waits indefinitely for a reply. Valid range is from

0 to 255 seconds.

For a Read, this is the address in the processor which is to return data.

Valid file types are S, B, T, C, R, N, and L.

Data Table Offset

(485CIF message types)

For a Write, this is the address in the processor which receives data.

Valid file types are I, O, S, B, T, C, R, N, L, and RTC

(1)(3)

.

This is the word offset value in the common interface file (byte offset for PLC device) in the target processor, which is to send the data.

Local Node Address Specifies the node number of the device that is receiving the message. Valid range is 0 to 31 for DH-485 protocol, 0 to 254 for DF1 protocol, or 0 to 63 for DeviceNet™.

Local/Remote Specifies whether the message is local or remote.

(1) Applies to MicroLogix 1200 Series B and later, and 1500 Series B and later.

(2) 485CIF write ST-to-485CIF only.

(3) 500CPU write RTC-to-Integer or RTC-to-RTC only.



Example 1 - Local Read from a 500CPU

Message Instruction Setup


In this example, the controller reads 10 elements from the target’s (Local

Node 2) N7 file, starting at word N7:50. The 10 words are placed in the controller’s integer file starting at word N7:0. If five seconds elapse before the message completes, error bit MG11:0/ER is set, indicating that the message timed out.

Valid File Type Combinations

Valid transfers between file types are shown below for MicroLogix messaging:

T

C

Local Data Types Communication Type Target Data Types

O

(1)

, I

(1)

, B, N, L

<---> read/write O, I, S, B, N, L

<--->

<---> read/write read/write

T

C

R

RTC

(2)

<---> read/write

---> write

R

N, RTC

(1) Output and input data types are not valid local data types for read messages.

(2) 500CPU write RTC-to-Integer or RTC-to-RTC only. Applies to MicroLogix 1200 Series B and later, and 1500 Series B and later only.

Example 2 - Local Read from a 485CIF



In this example, the controller reads five elements (words) from the target device’s (Local Node 2) CIF file, starting at word 20 (or byte 20 for non-SLC 500 devices). The five elements are placed in the controller’s integer file starting at word N7:0. If 15 seconds elapse before the message completes, error bit MG11:0/ER is set, indicating that the message timed out.



T

C


O

(1)

, I

(1)

, B, N, L

<---> read/write 485CIF

R

ST

(2)

<--->

<--->

<---> read/write read/write read/write

---> write

485CIF

485CIF

485CIF

485CIF


(2) Applies to MicroLogix 1200 Series B and later, and 1500 Series B and later only.



Example 3 - Local Read from a PLC-5



In this example, the controller reads 10 elements from the target device’s

(Local Node 2) N7 file, starting at word N7:50. The 10 words are placed in the controller’s integer file starting at word N7:0. If five seconds elapse before the message completes, error bit MG11:0/ER is set, indicating that the message timed out.



T

C


O

(1)

, I

(1)

, B, N, L

<---> read/write O, I, S, B, N, L

R

<--->

<--->

<---> read/write read/write read/write

T

C

R


1

Chapter

22

Data Logging

(MicroLogix 1500 1764-LRP Processor only)

Data Logging allows you to capture (store) application data as a record for retrieval at a later time. Each record is stored in a user-configured queue in battery backed memory (B-Ram). Records are retrieved from the

1764-LRP processor via communications. This chapter explains how Data

Logging is configured and used.

This chapter contains the following topics:

•

Queues and Records on page 22-2

•

Configuring Data Log Queues on pag e22-6

•

DLG - Data Log Instruction on pa ge22-8

•

Data Log Status File on pag e22-9

•

Retrieving (Reading) Records on page 22-11


22-2 Data Logging (MicroLogix 1500 1764-LRP Processor only)

Queues and Records

The 1764-LRP processor has 48K bytes (48 x 1024) of additional memory for data logging purposes. Within this memory, you can define up to 256

(0 to 255) data logging queues. Each queue is configurable by size

(maximum number of records stored), and by length (each record is 1 to

80 characters). The length and the maximum number of records determine how much memory is used by the queue. You can choose to have one large queue or multiple small queues.

The memory used for data logging is independent of the rest of the processor memory and cannot be accessed by the User Program. Each record is stored as the instruction is executed and is non-volatile

(battery-backed) to prevent loss during power-down.

Program Files

2

3

Data Files

0

1

4

2

5

6 to 255

3

4 to 255

Function Files

HSC

PTO

PWM

STI

EII

RTC

Specialty Files

Q0

Q1

Q2

Q3

Q4 to 255


Data Logging (MicroLogix 1500 1764-LRP Processor only) 22-3

Example Queue 0

This queue is used to show how to calculate the string length of each record and maximum number of records.

Table 22.1 Queue 0 (Date =

✔

, Time =

✔

, Delimiter = ,)

Record 0

Record 1

Record 2

Record 3

Record 4

Record 5

Record 6

Record 7

Record 8

Record 9

Date

01/10/2000 ,

Time

20:00:00 ,

N7:11

2315 ,

L14:0

103457 ,

T4:5.ACC

200

01/10/2000 , 20:30:00 , 2400 , 103456 , 250

01/10/2000 , 21:00:00 , 2275 , 103455 , 225

01/10/2000 , 21:30:00 , 2380 , 103455 , 223

01/10/2000 , 22:00:00 , 2293 , 103456 , 218

01/10/2000 , 22:30:00 , 2301 , 103455 , 231

01/10/2000 , 23:00:00 , 2308 , 103456 , 215

01/10/2000 , 23:30:00 , 2350 , 103457 , 208

01/11/2000 , 00:00:00 , 2295 , 103457 , 209

01/11/2000 , 00:30:00 , 2395 , 103456 , 211

Record 10 01/11/2000 , 01:00:00 , 2310 , 103455 , 224

Record 11 01/11/2000 , 01:30:00 , 2295 , 103456 , 233

I1:3.0

, 8190

, 8210

, 8150

, 8195

, 8390

, 8400

, 8100

, 8120

, 8145

, 8190

, 8195

, 8190

B3:2

, 4465

, 4375

, 4335

, 4360

, 4375

, 4405

, 4395

, 4415

, 4505

, 4305

, 4455

, 4495

String Length of Record

The size of a record is limited so that the length of the maximum formatted string does not exceed 80 characters. The following table can be used to determine the formatted string length.

Data

delimiter word long word date time

Memory Consumed

0 bytes

2 bytes

4 bytes

2 bytes

2 bytes

Formatted String Size

1 character

6 characters

11 characters

10 characters

8 characters

For queue 0, the formatted string length is 59 characters, as shown below:

Data

Characters 10

Date

1 8

Time

1 6

N7:11

1 11

L14:0

= 10 + 1 + 8 + 1 + 6 + 1 + 11 + 1 + 6 + 1 + 6 + 1 + 6

= 59 characters

T4:5.ACC

1 6 1 6

I1:3.0

1 6

I1:2.1



Number of Records

Using Queue 0 as an example, each record consumes:

Record Field

Date

Time

N7:11

L14:0

T4:5.ACC

I1:3.0

B3:2

Integrity Check

Total

Memory Consumption

2 bytes

2 bytes

2 bytes

4 bytes

2 bytes

2 bytes

2 bytes

2 bytes

18 bytes

In this example, each record consumes 18 bytes. So if one queue was configured, the maximum number of records that could be stored would be 2730. The maximum number of records is calculated by:

Maximum Number of Records = Data Log File Size/Record Size

= 48K bytes/18 bytes

= (48)(1024)/18

= 2730 records

Example Queue 5

Table 22.2 Queue 5 (Time =

✔

, Delimiter = TAB)

Record 0

Record 1

Record 2

Record 3

Record 4

Record 5

Record 6

Time

20:00:00

20:30:00

21:00:00

21:30:00

22:00:00

22:30:00

23:00:00

TAB

TAB

TAB

TAB

TAB

TAB

TAB

2315

N7:11

2400

2275

2380

2293

2301

2308

TAB 8190

I1:3.0

TAB 8210

TAB 8150

TAB 8195

TAB 8390

TAB 8400

TAB 8100

TAB

TAB

TAB

TAB

TAB

TAB

TAB

4465

I1:2.1

4375

4335

4360

4375

4405

4395

String Length of Record

The size of a record is limited so that the length of the maximum formatted string does not exceed 80 characters. The following table can be used to determine the formatted string length.

Data

delimiter word long word date time

Memory Consumed

0 bytes

2 bytes

4 bytes

2 bytes

2 bytes

Formatted String Size

1 character

6 characters

11 characters

10 characters

8 characters



For queue 5, the formatted string length is 29 characters, as shown below:

Data

Characters 8

Time

1 6

N7:11

1 6

I1:3.0

1 6

I1:2.1

= 8 + 1 + 6 + 1 + 6 + 1 + 6 = 29 characters

Number of Records

Using Queue 5 as an example, each record consumes:

Record Field

Time

N7:11

I1:3.0

I1:2.1

Integrity Check

Total

Memory Consumption

2 bytes

2 bytes

2 bytes

2 bytes

2 bytes

10 bytes

Each record consumes 10 bytes. So if only one queue was configured, the maximum number of records that could be stored would be 4915. The maximum number of records is calculated by:

Maximum Number of Records = Data Log File Size/Record Size

= 48K bytes/10 bytes

= (48)(1024)/10

= 4915 records



Configuring Data Log

Queues

Data Logging is configured using RSLogix 500 programming software version V4.00.00 or later.

1. Open a 1764-LRP application. The first step in using Data Logging is to configure the data log queue(s). Access to this function is provided via the RSLogix 500 Project tree:

Double-click

Configuration to access Data Log

Configuration.

2. The Data Log Que window appears. Double-click on Data Log

Configuration.

Appearance of Data

Log Que Configuration window before creating a queue.

3. The Data Log Que dialog box appears as shown below. Use this dialog box to enter the queue information.



Enter the following information:

Data Log Queue

Configuration Parameter

Description

Number of Records Defines the number of records (data sets) in the queue.

Separator Character

Date Stamp (optional)

Choose the character to act as the separator for the data in this queue (tab, comma, or space). The separator character may be the same or different for each queue configured.

if selected, the date is recorded in mm/dd/yyyy format

(1)

.

Time Stamp (optional)

Address to Log

if selected, the time is recorded in hh:mm:ss format

(1)

.

Enter the address of an item to be recorded and click on Accept to add the address to the Current Address List. The address can be any 16 or 32-bit piece of data.

Current Address List This is the list of items to be recorded. Record size can be up to 80 bytes. You can use the Delete button to remove items from this list.

See page 22-3 for information on record size.

A record consists of configured Date Stamp, Time Stamp, Current Address List, and Separator

Characters.

(1) If the real-time clock is not present on the controller and Date Stamp and Time Stamp are selected (enabled), the date is recorded as 00/00/0000 and the time as 00:00:00.

4. After entering all the information for the data log queue, click on OK.

The queue is added to the Data Log Que window with a corresponding queue number. This is the queue number to use in the

DLG instruction.



DLG - Data Log

Instruction

Data Log queue number 0


Table 22.3 Execution Time for the DLG Instruction


True

MicroLogix 1500 1764-LRP 67.5

µ s + 11.8

µ s/date stamp

+ 12.4

µ s/time stamp

+ 9.1

µ s/word logged

+ 16.2

µ s/long word logged

False

6.7

µ s

IMPORTANT

You must configure a data log queue before programming a DLG instruction into your ladder program.

The DLG instruction triggers the saving of a record. The DLG instruction has one operand:

Queue Number - Specifies which data log queue captures a record.

The DLG instruction only captures data on a false-to-true rung transition.

The DLG rung must be reset (scanned false) before it will capture data again. Never place the DLG instruction alone on a rung. It should always have preceding logic, as shown below:

DLG



Data Log Status File


There is a Data Log Status (DLS) file element for each Data Log Queue.

The DLS file does not exist until a data log queue has been configured.

The Data Log Status file has 3-word elements. Word 0 is addressable by bit only through ladder logic. Words 1 and 2 are addressable by word and/or bit through ladder logic.

The number of DLS file elements depends upon the number of queues specified in the application. The status bits and words are described below.

Table 22.4 Data Log Status (DLS) File Elements

Control Element

Word 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

0

1

EN

(1) 0

DN

(2)

OV

(3) 0 0 0

FSZ = File Size (number of records allocated)

0 0 0 0 0 0 0 0 0

2 RST = Records Stored (number of records recorded)

(1) EN = Enable Bit

(2) DN = Done Bit

(3) OV = Overflow Bit

Data Logging Enable (EN)

When the DLG instruction rung is true, the Data Logging Enable (EN) is set (1) and the DLG instruction records the defined data set. To address this bit in ladder logic, use the format: DLS0:Q/EN, where Q is the queue number.

Data Logging Done (DN)

The Data Logging Done (DN) bit is used to indicate when the associated queue is full. This bit is set (1) by the DLG instruction when the queue becomes full. This bit is cleared when a record is retrieved from the queue. To address this bit in ladder logic, use the format: DLS0:Q/DN, were Q is the queue number.

Data Logging Overflow (OV)

The Data Logging Overflow (OV) bit is used to indicate when a record gets overwritten in the associated queue. This bit is set (1) by the DLG instruction when a record is overwritten. Once set, the OV bit remains set until you clear (0) it. To address this bit in ladder logic, use the format:

DLS0:Q/OV, where Q is the queue number.



File Size (FSZ)

File Size (FSZ) shows the number of records that are allocated for this queue. The number of records is set when the data log queue is configured. FSZ can be used with RST to determine how full the queue is.

To address this word in ladder logic, use the format: DLS0:Q.FSZ, where

Q is the queue number.

Records Stored (RST)

Records Stored (RST) specifies how many data sets are in the queue. RST is decremented when a record is read from a communications device. To address this word in ladder logic, use the format: DLS0:Q.RST, where Q is the queue number.

NOTE

If a queue is full and another record is saved, the oldest record is over-written. Queue behavior is the same as a

FIFO stack—first in, first out. If a queue is full and an additional record is saved, the “first” record is deleted.

DLS information can be used in the following types of instructions:

Instruction Type

Relay (Bit)

Compare

Math

Logical

Move

Operand

Destination Output Bit

Source A

Source B

Low Limit (LIM instruction)

Test (LIM instruction)

High Limit (LIM instruction)

Source (MEQ instruction)

Mask (MEQ instruction)

Compare (MEQ instruction)

Source A

Source B

Input (SCP instruction)

Source A

Source B

Source



Retrieving (Reading)

Records

Data is retrieved from a data logging queue by sending a logical read command that addresses the Data Log retrieval file. The oldest record is retrieved first and then, deleted. The record is deleted as soon as it is queued for transmission. If there is a power failure before the transmission is complete, the record is lost.

The data is retrieved as an ASCII string with the following format:

<date><UDS><time><UDS><1 st

Data><UDS><2 nd

Data><UDS>…<UDS><Last Data><NUL>

• where:

<date> = mm/dd/yyyy - ASCII characters (date is optional)

<time> = hh:mm:ss - ASCII characters (time is optional)

<UDS> = User Defined Separator (TAB, COMMA, or SPACE)

<X Data> = ASCII decimal representation of the value of the data

<NUL> = record string is null terminated

•

If the Real Time Clock module is not present in the controller, <date> is formatted as 00/00/0000, and

<time> is formatted as 00:00:00.

•

The Communications Device determines the number of sets of data that have been recorded but not

retrieved. See the Data Log Status File on p age22-9.

•

The controller performs a the data integrity check for each record. If the data integrity check is invalid, a failure response is sent to the Communications Device. The data set is deleted as soon as the failure response is queued for transmission.

NOTE

For easy use with Microsoft Excel, use the TAB character as the separator character.

Accessing the Retrieval

File

You can use a dedicated retrieval tool or create your own application.

Retrieval Tools

There are a number of retrieval tools designed for use with Palm™ OS,

Windows™ CE, Windows 9x, and Windows NT. You can download these free tools from our web site. Visit http://www.ab.com/micrologix.



Information for Creating Your Own Application

Table 22.5 Command Structure

DST SRC CMD 0f STS

Controller Receives Communications Packet

TNS FNC A2 Byte Size File No.

File Tpe Ele. No.

S/Ele. No.

Field

DST

SRC

CMD

STS

TNS

FNC

Byte Size

File Number

File Type

Element Number

Sub/Element Number

Function

Destination Node

Source Node

Command Code

Status Code

Transaction Number

Function Code

Number of bytes to be read

Description

Set to zero (0)

Always 2 bytes

Queue number

Formatted string length (see equation below)

Always set to zero (0)

Must be A5 (hex)

Determines the queue to be read (0 to 255)

Always set to zero (0)

Table 22.6 Equation

Record Field 1 + Record Field 2 + Record Field 3 … + Record Field 7 = Formatted

String Length

Table 22.7 Record Field Sizes

Data Type

Word

Long Word

Date Field

Time Field

Maximum Size

7 bytes (characters)




NOTE

The formatted string length cannot exceed 80 bytes in length.

NOTE

The last byte will be a zero value representing the terminator character.



Controller Responds with Reply

Field

SRC

DST

CMD

STS

TNS

DATA

Table 22.8 Reply Structure

SRC DST CMD 4f

Function

Source Node

Destination Node

Command Code

Status Code

Transaction Number

STS TNS

Description

Always 2 bytes

Formatted string

DATA EXT STS

If the data integrity check fails, the record is deleted and an error is sent with STS of 0xF0 and ext STS of 0x0E.

For more information on writing a DF1 protocol, refer to Allen-Bradley publication 1770-6.5.16, DF1 Protocol and Command Set Reference

Manual (available from www.theautomationbookstore.com).

Conditions that Will

Erase the Data Retrieval

File

IMPORTANT

The data in the retrieval file can only be read once.

Then it is erased from the processor.

The following conditions will cause previously logged data to be lost:

•

Program download from RSLogix 500 to controller.

•

Memory Module transfer to controller except for Memory Module

autoload of the same program.

•

Full Queue - when a queue is full, new records are recorded over the existing records, starting at the beginning of the file. You can put the following rung in your ladder program to prevent this from happening:

B3:1

1

Less Than or Eql (A<=B)

Source A DLS0:5.RST

Source B DLS0:5.FSZ





1

Appendix

A

MicroLogix 1200 Memory Usage and Instruction

Execution Time

This appendix contains a complete list of the MicroLogix 1200 programming instructions. The list shows the memory usage and instruction execution time for each instruction. Execution times using indirect addressing and a scan time worksheet are also provided.

Programming

Instructions Memory

Usage and Execution

Time

.

The table below lists the execution times and memory usage for the programming instructions. These values depend on whether you are using word or long word as the data format

Table A.1 MicroLogix 1200 Memory Usage and Instruction Execution Time for Programming Instructions

Programming Instruction

ASCII Test Buffer for Line

(1)

Instruction

Mnemonic

ABL

ACB

Word

Execution Time in µs Memory

False True

Usage in

Words

12.5

3.3

False True

Memory

Usage in

Words

Long Word addressing level does not apply.

12.1

115 + 8.6/ char.

103.1

3.3

Long Word

Execution Time in µs

ASCII Number of Characters in

Buffer

(1)

ASCII String to Integer

(1)

ACI

0.0

0.0

24.6 + 11.6/char.

1.5

ASCII Clear Buffer

ASCII String Concatenate

(1)

Add

ASCII String Extract

(1)

ASCII Handshake Lines

(1)

ASCII Integer to String

And

ASCII Read Characters

(1)

ASCII Read Line

(1)

ACL

ACN

ADD

AEX

AHL

AIC

AND

ARD

ARL

0.0

0.0

0.0

0.0

11.9

0.0

0.0

11.8

11.7

17.6 + 7.2/ char.

clear: both 249.1

receive 28.9

transmit 33.6

22.6 + 11.5/ char.

2.7

14.8 + 2.9/ char.

109.4

1.5

1.2

2.0

3.3

2.5

5.3

1.4

29.3 +5.2/ char.

2.2

132.3 + 49.7/ char.

139.7 + 50.1/ char.

2.8

4.3

4.3


0.0

11.9

3.5


0.0

82.0

1.6

0.0

9.2

3.0



A-2 MicroLogix 1200 Memory Usage and Instruction Execution Time



ASCII String Search

Bit Shift Left

Bit Shift Right

Clear

File Copy

Count Down

Count Up

Decode 4-to-1 of 16

Divide

Encode 1-of-16 to 4

Equal

FIFO Load

FIFO Unload

Fill File

Convert from BCD

Interrupt Subroutine

Jump

Less Than

LIFO Load

LIFO Unload

Limit

(1)

ASCII String Compare

Jump to Subroutine

Label

Less Than or Equal To

Master Control Reset

(1)

ASCII Write with Append

ASCII Write

Greater Than or Equal To

Greater Than

High-Speed Load

Immediate Input with Mask

Immediate Output with Mask

Instruction

Mnemonic

ASC

ASR

AWA

AWT

BSL

BSR

CLR

COP

CTD

CTU

DCD

DIV

ENC

EQU

FFL

FFU

FLL

FRD

GEQ

GRT

HSL

IIM

INT

IOM

JMP

JSR

LBL

LEQ

LES

LFL

LFU

1.3

1.3

0.0

0.0

9.0

9.2

0.0

0.0

0.0

1.1

11.1

10.4

0.0

0.0

1.1

1.1

0.0

0.0

1.0

0.0

0.0

0.0

1.0

1.1

Word


False True

Usage in

Words

0.0

6.0

16.2 + 4.0/ matching char.

0.0

14.1


1.8

268 + 12/char. 3.4

14.1

268 + 12/char. 3.4

Long Word


False True

Memory

Usage in

Words


1.1

10.4

10.4

LIM

6.1

MCR (Start) 1.2

MCR (End)

1.6

Masked Comparison for Equal MEQ

Move MOV

1.8

0.0

32 + 1.3/word 3.8

32 + 1.3/word 3.8

1.3

1.0

19 + 0.8/word 2.0

9.0

9.0

1.9

12.2

7.2

1.3

11.3

2.4

2.4

1.9

2.0

1.5

1.3

3.4

33 + 0.8/word 3.4

14 + 0.6/word 2.0

14.1

1.5

1.3

1.3

46.7

26.4

1.0

22.3

1.0

8.4

1.0

1.3

1.3

25.5

29.1

6.4

1.2

1.6

1.9

2.4

1.3

1.3

7.3

3.0

0.3

3.0

0.5

1.5

0.5

1.3

1.3

3.4

3.4

2.3

1.0

1.5

1.8

2.5

0.0


0.0

1.9

11.2

10.4

0.0


2.7

2.7

0.0


2.7

2.7

10.4

10.4

15 + 1.2/long word 2.5

2.8

2.8

47.3

2.8

2.8

31.6

31.6

2.9

2.4

7.8

2.9

2.9

3.9

3.4

13.6

14.4

4.0


3.1

0.0

6.3

42.8

2.8

11.7

1.0

3.5


2.6

3.9

36 + 1.5/long word 3.4

3.9

8.3

3.5

2.0


MicroLogix 1200 Memory Usage and Instruction Execution Time A-3



Message, Steady State

Message, False-to-True

Transition for Reads


Transition for Writes

Multiply

Masked Move

Negate

Not Equal

Not

One Shot

Or

One Shot Falling

One Shot Rising

Output Enable

Output Latch

Output Unlatch

Proportional Integral Derivative PID


(1)

PTO


Reset Accumulator

(1)

PWM

RAC

OR

OSF

OSR

OTE

OTL

OTU

I/O Refresh

Reset

Return

Retentive Timer On

Subroutine

Scale

Scale with Parameters

Sequencer Compare

Sequencer Load

Sequencer Output

Subtract

Suspend

Service Communications

Swap

(1)

Temporary End

Instruction

Mnemonic

MSG

MUL

MVM

NEG

NEQ

NOT

ONS

REF

RES

RET

RTO

SBR

SCL

SCP

SQC

SQL

SQO

Square Root SQR

Selectable Timed Interrupt Start STS

SUB

SUS

SVC

SWP

TND

Word


False True

Usage in

Words

6.0

20.0

2.9

230.0

Long Word


False True

Memory

Usage in

Words


0.0

0.0

0.0

1.1

0.0

1.9

0.0

3.7

3.0

1.1

0.0

0.0

11.0

24.4

264 + 1.6/ word

6.8

7.8

2.9

1.3

2.4

2.6

2.2

2.8

3.4

1.4

1.0

1.1

295.8

85.6

24.7

126.6

1.9

0.0

0.0

0.0

n/a

0.0

0.0

7.1

7.0

7.1

0.0

2.4

1.0

0.0

Word addressing level does not apply.

0.0

0.0

see p. A-7

5.9

0.5

1.0

1.0

18.0

1.0

10.5

0.3

3.4

0.3

2.5

0.0

0.0

31.5

23.5

21.7

23.2

26.0

57.5

3.4

n/a

208 + 1.6/ word

(2)

13.7 + 2.2/ swapped word

0.9

1.5

0.5

1.5

1.0

3.3

1.5

1.0

3.8

3.9

3.4

3.9

2.8

5.4

5.4

1.6

0.6

0.6

2.4

1.9

2.0

2.0

3.0

1.3

2.5

3.5

0.0

0.0

0.0

2.7

0.0


0.0


0.0


0.0

7.1

7.1

7.1

0.0

31.9

11.8

12.1

2.5

9.2

9.2

21.2

52.2

26.3

24.3

26.6

30.9

3.5

3.0

3.0

2.5

2.5

3.0

2.0

6.0

4.4

3.9

4.4

2.5


0.0

12.9

3.5





Programming Instruction Instruction

Mnemonic

Convert to BCD

Off-Delay Timer

On-Delay Timer

User Interrupt Disable

User Interrupt Enable

TOD

TOF

TON

UID

UIE

User Interrupt Flush

Examine if Closed

Examine if Open

UIF

XIC

XIO

Exclusive Or XOR

(1) Only valid for MicroLogix 1200 Series B Controllers.

Word


False True

Usage in

Words

0.0

17.2

1.8

13.0

2.9

3.9

3.0

0.0

0.0

0.0

0.8

0.8

0.0

18.0

0.8

0.8

12.3

0.9

0.9

3.0

3.9

0.9

0.9

0.9

1.0

1.0

2.8

Long Word


False True

Memory

Usage in

Words


0.0

9.9

3.0




Indirect Addressing

The following sections describe how indirect addressing affects the execution time of instructions for the Micrologix 1200 controllers. The timing for an indirect address is affected by the form of the indirect address.

For the address forms in the following table, you can interchange the following file types:

•

Input (I) and Output (O)

•

Bit (B), Integer (N)

•

Timer (T), Counter (C), and Control (R)

Execution Times for the Indirect Addresses

For most types of instructions that contain an indirect address(es), look up the form of the indirect address in the table below and add that time to the execution time of the instruction.

[*] indicates that an indirect reference is substituted.

Table A.2 MicroLogix 1200 Instruction Execution Time Using Indirect Addressing

T[*]:[*]

T4:[*].ACC

T[*]:1.ACC

T[*]:[*].ACC

O:1.[*]/2

O:[*].0/2

O:[*].[*]/2

O:1.0/[*]

O:1.[*]/[*]

O:[*].0/[*]

O:[*].[*]/[*]

B3:[*]/2

B[*]:1/2

B[*]:[*]/2

Address Form

O:1.[*]

O:[*].0

O:[*].[*]

B3:[*]

B[*]:1

B[*]:[*]

L8:[*]

L[*]:1

L[*]:[*]

T4:[*]

T[*]:1

15.9

6.8

7.6

16.6

16.9

6.3

24.5

25.3

24.2

6.5

24.4

24.9

6.3

15.2

24.5

6.1

24.4

24.3

6.0

24.0

Operand Time (µs) Address Form

5.8

B3:1/[*]

15.0

B3:[*]/[*]

15.1

5.8

24.3

B[*]:1/[*]

B[*]:[*]/[*]

L8:[*]/2

L[*]:1/2

L[*]:[*]/2

L8:1/[*]

L8:[*]/[*]

L[*]:1/[*]

L[*]:[*]/[*]

T4:[*]/DN

T[*]:1/DN

T[*]:[*]/DN

T4:[*].ACC/2

T[*]:1.ACC/2

T[*]:[*].ACC/2

T4:1/[*]

T4:[*]/[*]

T[*]:1/[*]

T[*]:[*]/[*]

T4:1.ACC/[*]

T4:[*].ACC/[*]

T[*]:1.ACC/[*]

T[*]:[*].ACC/[*]

6.5

8.3

26.1

26.8

6.9

8.9

26.1

27.3

6.6

24.4

24.9

7.4

24.4

25.9

24.6

25.3

6.8

7.7

26.0

25.9

Operand Time (µs)

6.8

7.6

25.9

26.2

6.5



Execution Time Example – Word Level Instruction Using and Indirect Address

ADD Instruction Addressing

•

Source A: N7:[*]

•

Source B: T4:[*].ACC

•

Destination: N[*]:[*]

ADD Instruction Times

•

ADD Instruction: 2.7 µs

•

Source A: 5.8

µ s

•

Source B: 6.5

µ s

•

Destination: 24.5

µ s

Total = 36.5

µ s

Execution Time Example – Bit Instruction Using an Indirect Address

XIC B3/[*]

•

XIC: 0.9

µ s + 5.8

µ s = 6.7

µ s True case

•

XIC: 0.9

µ s + 5.8

µ s = 6.7

µ s False case



MicroLogix 1200

Scan Time Worksheet

Calculate the scan time for your control program using the worksheet below.

Input Scan (sum of below)

Overhead (if expansion I/O is used)

Expansion Input Words X 10 µs (or X 14 µs if Forcing is used)

Number of modules with Input words X 80 µs

= 55 µs

=

=

Input Scan Sub-Total =

Program Scan

Add execution times of all instructions in your program when executed true

Program Scan Sub-Total

Output Scan (sum of below)

Overhead (if expansion I/O used)

=

= 30 µs

=

Expansion Output Words X 3 µs (or X 7 µs if Forcing is used) =

Output Scan Sub-Total =

Communications Overhead

(1)

Worst Case

Typical Case

=1470 µs

= 530 µs

Use this number if the communications port is configured, but not communicating to any other device.

= 200 µs

Use this number if the communications port is in “Shutdown” mode.

= 0 µs

Communications Overhead Sub-Total =

System Overhead

Add this number if your system includes a 1762-RTC or 1762-MM1RTC.

Housekeeping Overhead

= 100 µs

= 270 µs

System Overhead Sub-Total =

Totals

Sum of all sub-totals

Multiply by Communications Multiplier from Table X

Total Estimated Scan Time =

(1) Communications Overhead is a function of the device connected to the controller. This will not occur every scan.

Communications Multiplier Table

Protocol

Multiplier at Various Baud Rates

38.4K

19.2K

9.6K

DF1 Full-Duplex 1.50

DF1 Half Duplex Slave 1.21

DH-485 N/A

1.27

1.14

1.16

1.16

1.10

1.11

4.8K

1.12

1.09

N/A

2.4K

1.10

1.08

N/A

1.2K

1.09

1.08

N/A

600

1.09

1.08

N/A

300

1.08

1.07

N/A

Modbus™

Shut Down

1.22

1.00

1.13

1.00

1.10

1.00

1.09

1.00

1.09

1.00

1.09

1.00

1.09

1.00

1.09

1.00

(1) Inactive is defined as No Messaging and No Data Monitoring. For DH-485 protocol, inactive means that the controller is not connected to a network.

Inactive

(1)

1.00

1.01

1.10 at 19.2K

1.07 at 9.6K

1.00

1.00




Appendix

B

MicroLogix 1500 Memory Usage and Instruction

Execution Time

This appendix contains a complete list of the MicroLogix 1500 programming instructions. The list shows the memory usage and instruction execution time for each instruction. Execution times using indirect addressing and a scan time worksheet are also provided.

1

Programming

Instructions Memory usage and Execution

Time

The tables below lists the execution times and memory usage for the programming instructions. These values depend on whether you are using word or long word as the data format.

Table B.1 MicroLogix 1500 Controllers -

Memory Usage and Instruction Execution Time for Programming Instructions


ASCII Test Buffer for Line

(1)

ASCII Number of Characters in

Buffer

(1)

ASCII String to Integer

(1)

Instruction

Mnemonic

ABL

ACB

Word Long Word


False True

Usage in

Words

11.4

94 + 7.6/char. 3.3


False True

Memory

Usage in

Words


11.0

84.2

3.3

ACI

0.0

0.0

20.3 + 9.5/char.

1.5

ASCII Clear Buffer

(1)

ASCII String Concatenate

(1)

Add

ASCII String Extract

(1)

ASCII Handshake Lines

(1)

ASCII Integer to String

(1)

And

ASCII Read Characters

(1)

ASCII Read Line

(1)

ASCII String Search

(1)

ACL

ACN

ADD

AEX

AHL

AIC

AND

ARD

ARL

ASC

0.0

0.0

0.0

0.0

10.8

0.0

0.0

10.7

10.6

0.0

14.2 + 6.3/ char.

clear: both 203.9

receive 24.7

transmit 29.1

17.9 + 10.2/ char.

2.5

12.4 + 2.6/ char.

89.3

1.5

1.2

2.0

3.3

2.5

5.3

25 + 4.3/char. 1.4

2.0

2.8

108 + 44/char. 4.3

4.3

114 + 44.3/ char.


6.0


0.0

10.4

3.5


0.0

68.7

1.6

0.0

7.9

3.0



B-2 MicroLogix 1500 Memory Usage and Instruction Execution Time




ASCII String Compare

ASCII Write

Clear

File Copy

Count Down

Count Up

Decode 4-to-1 of 16

Divide

Data Log

Encode 1-of-16 to 4

Equal

FIFO Load

FIFO Unload

Convert from BCD

Greater Than or Equal To

Greater Than

High-Speed Load

Immediate Input with Mask

Interrupt Subroutine

Immediate Output with Mask

Jump

Jump to Subroutine

Label

Less Than or Equal To

Less Than

(1)

(1)

ASCII Write with Append

Bit Shift Left

Bit Shift Right

Fill File

(1)

FRD

GEQ

GRT

HSL

IIM

INT

IOM

JMP

JSR

LBL

LEQ

LES

CTD

CTU

DCD

DIV

DLG

Instruction

Mnemonic

ASR

AWA

AWT

BSL

BSR

CLR

COP

ENC

EQU

FFL

FFU

FLL

0.0

0.0

1.0

0.0

0.0

0.0

1.1

1.1

0.0

0.0

1.0

1.1

1.1

Word


False True

Usage in

Words

0.0


1.8

Long Word


False True

Memory

Usage in

Words


12.5

3.4

12.8

1.4

1.4

0.0

0.0

236 + 10.6/ char.

237 + 10.6/ char.

26.4 + 1.06/ word

26.1 + 1.07/ word

1.2

3.4

3.8

3.8

1.0

2.0

0.0

5.5

1.0


8.5

8.5

15.9 + 0.67/ word

7.5

6.4

2.4

2.4

0.0

0.0

6.7

0.0

1.1

9.8

9.7

0.9

10.3

67.5 + 11.8/ date stamp

+12.4/time stamp

+9.1/word logged

6.8

1.2

10.0

27.7 + 0.65/ word

1.9

2.0

2.4

1.5

1.3

3.4

3.4

0.0

6.7

36.7

67.5 + 11.8/date stamp

+12.4/time stamp

+16.2/long word logged

3.5

2.4


1.9

9.7

9.7

2.6

10.9

29.4 + 1.25/long word

2.6

3.9

3.4

19.4

1.0

8.0

1.0

1.2

1.2

12.1 + 0.43/ word

12.3

1.2

1.2

39.7

22.5

1.0

2.0

1.5

1.3

1.3

7.3

3.0

0.3

3.0

0.5

1.5

0.5

1.3

1.3

0.0

12.3 + 0.8/long word

2.5


2.5

2.6

2.9

2.5

0.0

2.6

40.3

2.4

7.8


2.5

2.5

2.6

2.6

2.9

2.9


MicroLogix 1500 Memory Usage and Instruction Execution Time B-3




LIFO Load

LIFO Unload

Limit

Master Control Reset

Instruction

Mnemonic

Word


False True

Usage in

Words

LFL

LFU

9.7

9.7

LIM

5.3

MCR (Start) 0.8

22.2

25.6

5.5

0.8

3.4

3.4

2.3

1.0

Long Word


False

9.7

9.7

True

27.4

27.4

Memory

Usage in

Words

3.9

3.4

11.7

12.2

4.0


MCR (End)

1.0

Masked Comparison for Equal MEQ

1.7

Move

Message, Steady State


Transition for Reads

MOV

MSG

0.0

6.0

1.0

1.7

2.3

17.0

198.0

1.5

1.8

2.5

2.9

2.9

0.0

3.5

6.8

3.5

2.0



Transition for Writes

Multiply

Masked Move

Negate

Not Equal

Not

One Shot

Or

One Shot Falling

One Shot Rising

Output Enable

Output Latch

Output Unlatch


Reset Accumulator

I/O Refresh

Reset

Return

Retentive Timer On

Subroutine

Scale

Scale with Parameters

Sequencer Compare

Sequencer Load

Sequencer Output

Square Root

MUL

MVM

NEG

NEQ

NOT

ONS

OR

OSF

OSR

OTE

OTL

OTU

Proportional Integral Derivative PID

Pulse Train Output PTO

PWM

RAC

REF

RES

RET

RTO

SBR

SCL

SCP

SQC

SQL

SQO

SQR

Selectable Timed Interrupt Start STS

0.0

0.0

0.0

1.1

0.0

1.7

0.0

3.4

2.8

0.0

0.0

0.0

8.9

21.1

226 + 1.4/ word

5.8

7.2

1.9

1.2

2.4

2.2

2.0

2.7

3.2

1.2

0.9

0.9

251.8

72.6

2.0

2.0

3.0

1.3

2.5

3.5

2.8

5.4

5.4

1.6

0.6

0.6

2.4

1.9

21.1

107.4

1.9

Word addressing level does not apply.

0.0

see p. B-6

0.5

0.0

4.8

1.0

0.0

2.2

1.0

0.0

0.0

6.3

6.3

6.3

0.0

0.0

1.0

15.8

1.0

8.7

27.0

20.1

19.1

20.0

22.3

50.7

0.3

3.4

0.3

2.5

3.8

3.9

3.4

3.9

1.5

1.0

0.1

0.0

0.0

2.5

0.0


0.0


0.0


0.0

6.3

6.3

6.3

0.0

27.6

10.0

10.4

2.3

8.1

7.9

17.8

44.7

22.7

21.1

23.1

26.0

3.5

3.0

3.0

2.5

2.5

3.0

2.0

6.0

4.4

3.9

4.4

2.5







Subtract

Suspend


(service one channel)


(service two channels)

Swap

(1)

Temporary End

Convert to BCD

Off-Delay Timer

On-Delay Timer

User Interrupt Disable

User Interrupt Enable

User Interrupt Flush

Examine if Closed

Examine if Open

Exclusive Or

Instruction

Mnemonic

SUB

SUS

SVC

SWP

UID

UIE

UIF

XIC

TND

TOD

TOF

TON

XIO

XOR

(2)

0.0

0.0

0.0

0.0

Word


False True

Usage in

Words

0.0

N/A

0.0

2.9

N/A

166 + 1.4/ word

3.3

1.5

1.0

Long Word


False True

Memory

Usage in

Words

0.0

11.2

3.5


0.0

1.0

0.0

0.0

0.0

10.9

2.5

0.0

0.0

0.8

0.8

10.6

0.9

0.9

2.3

1.0

14.3

2.5

15.5

327 + 1.4/ word

11.7 + 1.8/ swapped word

1.5

0.5

1.8

3.9

3.9

0.9

0.9

0.9

1.0

1.0

2.8

0.0

8.9

3.0

(1) Only valid for MicroLogix 1500 Series B Processors.


Indirect Addressing

The following sections describe how indirect addressing affects the execution time of instructions in the Micrologix 1500 processor. The timing for an indirect address is affected by the form of the indirect address.

For the address forms in the following table, you can interchange the following file types:

•

Input (I) and Output (O)

•

Bit (B), Integer (N)

•

Timer (T), Counter (C), and Control (R)


MicroLogix 1500 Memory Usage and Instruction Execution Time B-5

Execution Times for the Indirect Addresses

For most types of instructions that contain an indirect address(es), look up the form of the indirect address in the table below and add that time to the execution time of the instruction.

[*] indicates that an indirect reference is substituted.

Table B.2 MicroLogix 1500 Controllers

Instruction Execution Time Using Indirect Addressing

Address

Form

O:1.[*]

O:[*].0

O:[*].[*]

B3:[*]

B[*]:1

B[*]:[*]

L8:[*]

L[*]:1

L[*]:[*]

T4:[*]

T[*]:1

T[*]:[*]

4.9

19.7

19.8

T4:[*].ACC

T[*]:1.ACC

5.1

19.9

T[*]:[*].ACC

20.5

O:1.[*]/2

O:[*].0/2

5.4

12.8

4.8

19.9

20.1

5.2

20.4

20.1

Operand

Time (µs)

4.8

12.3

12.4

Address

Form

O:[*].[*]/2

O:1.0/[*]

O:1.[*]/[*]

O:[*].0/[*] 14.1

O:[*].[*]/[*] 14.5

B3:[*]/2 5.4

B[*]:1/2

B[*]:[*]/2

B3:1/[*]

20.4

21.0

5.9

Operand

Time (µs)

13.3

5.9

6.5

B3:[*]/[*]

B[*]:1/[*]

B[*]:[*]/[*]

L8:[*]/2

L[*]:1/2

L[*]:[*]/2

L8:1/[*]

L8:[*]/[*]

6.5

21.6

22.3

5.5

20.4

21.0

5.9

6.5

Address

Form

L[*]:1/[*]

L[*]:[*]/[*]

T4:[*]/DN

T[*]:1/DN 20.4

T[*]:[*]/DN 20.7

T4:[*].ACC/2 6.4

T[*]:1.ACC/2 20.4

T[*]:[*].ACC/2 21.6

T4:1/[*] 5.9

Operand

Time (µs)

21.6

21.9

5.7

T4:[*]/[*]

T[*]:1/[*]

T[*]:[*]/[*]

7.1

21.8

22.4

T4:1.ACC/[*] 6.0

T4:[*].ACC/[*] 7.5

T[*]:1.ACC/[*] 21.8

T[*]:[*].ACC/[*] 22.9

Execution Time Example – Word Level Instruction Using an Indirect Address

ADD Instruction Addressing

Source A: N7:[*]

Source B: T4:[*].ACC

Destination: N[*]:[*]

ADD Instruction Times

ADD Instruction: 2.5 µs

Source A: 4.8

µ s

Source B: 5.1

µ s

Destination: 20.1

µ s

Total = 32.5

µ

s

Execution Time Example – Bit Instruction Using an Indirect Address

XIC B3/[*]

•

XIC: 0.9

µ s + 4.8

µ s = 5.7

µ s True case

•

XIC: 0.0

µ s + 4.8

µ s = 4.8

µ s False case



MicroLogix 1500

Scan Time Worksheet

Calculate the scan time for your control program using the worksheet below.

Input Scan (sum of below)

Overhead (if expansion I/O is used)

Expansion Input Words X 3 µs (or X 7.5 µs if Forcing is used)

Number of modules with Input words X 10 µs

= 53 µs

=

=

Input Scan Sub-Total =

Program Scan

Add execution times of all instructions in your program when executed true =

Program Scan Sub-Total =

Output Scan (sum of below)

Overhead (if expansion I/O used)

Expansion Output Words X 2 µs (or X 6.5 µs if Forcing is used)

= 29 µs

=

Output Scan Sub-Total =

Communications Overhead

(1)

Worst Case

Typical Case

= 1100 µs

= 400 µs

Use this number if the communications port is configured, but not communicating to any other device

= 150 µs

Use this number if the communications port is in Shutdown mode = 0 µs

System Overhead

Add this number if your system includes a 1764-RTC, 1764-MM1RTC, or MM2RTC. = 80 µs

Add this number if your system includes a 1764-DAT = 530 µs

Housekeeping Overhead = 240 µs 240

System Overhead Sub-Total =

Totals

Pick one of the four numbers for Channel 0

Pick one of the four numbers for Channel 1

Communications Overhead Sub-Total=

Sum of all

Multiply by Communications Multiplier from Table X

Time Tick Multiplier (X1.02)

Total Estimated Scan Time =

(1) Communications Overhead is a function of the device connected to the controller. This will not occur every scan.

Communications Multiplier Table

Protocol

Multiplier at Various Baud Rates

38.4K

DF1 Full Duplex 1.39

DF1 Half Duplex 1.18

DH-485 N/A

19.2K

1.20

1.12

1.14

9.6K

1.13

1.09

1.10

4.8K

1.10

1.08

N/A

2.4K

1.09

1.07

N/A

1.2K

1.08

1.07

N/A

600

1.08

1.06

N/A

300

1.08

1.06

N/A

Modbus

(2)

ASCII

(2)

Shut Down

1.21

1.52

1.00

1.12

1.33

1.00

1.09

1.24

1.00

1.08

1.20

1.00

1.08

1.19

1.00

1.08

1.18

1.00

1.08

1.18

1.00

1.08

1.17

1.00

(1) Inactive is defined as No Messaging and No Data Monitoring. For DH-485 protocol, inactive means that the controller is not conne cted to a network.

(2) Applies to MicroLogix 1500 Series B Processors only.

Inactive

(1)

1.00

1.01

1.06 at 19.2K

1.09 at 9.6K

1.00

1.00

1.00


Appendix

C

System Status File

The status file lets you monitor how your controller works and lets you direct how you want it to work. This is done by using the status file to set up control bits and monitor both hardware and programming device faults and other status information.

IMPORTANT

Do not write to reserved words in the status file. If you intend writing to status file data, it is imperative that you first understand the function fully.


C-2 System Status File

Status File Overview

The status file (S:) contains the following words:

S:42

S:53

S:57

S:58

S:59

S:60

S:36/10

S:37

S:38

S:39

S:40

S:41

S:61

S:62

S:63

S:64L

S:64H

S:22

S:29

S:30

S:31

S:33

S:35

S:8

S:9

S:10

S:13, S:14

S:15L

S:15H

Address

S:0

S:1

S:2

S:2/9

S:2/15

S:3H

S:4

S:5

S:6

S:7

Function

Arithmetic Flags

Controller Mode

STI Mode

Memory Module Program Compare

Math Overflow Selection

Watchdog Scan Time

Free Running Clock

Minor Error Bits

Major Error Code

Suspend Code

Suspend File

Active Nodes (Nodes 0 to 15)

Active Nodes (Nodes 16 to 31)

Math Register

Node Address

Baud Rate

Maximum Scan Time

User Fault Routine File Number

STI Set Point

STI File Number

Channel 0 Communications

Last 100 µSec Scan Time

Data File Overwrite Protection Lost

RTC Year

RTC Month

RTC Day of Month

RTC Hours

RTC Minutes

RTC Seconds

RTC Day of Week

OS Catalog Number

OS Series

OS FRN

Processor Catalog Number

Processor Series

Processor Revision

User Program Functionality Type

Compiler Revision - Build Number

Compiler Revision - Release

C-19

C-19

C-20

C-20

C-20

C-20

C-18

C-18

C-18

C-18

C-19

C-19

C-20

C-20

C-21

C-21

C-21

C-15

C-16

C-16

C-16

C-16

C-17

C-14

C-14

C-14

C-15

C-15

C-15

C-10

C-10

C-10

C-11

C-13

C-14

Page

C-3

C-4

C-9

C-9


Status File Details

System Status File C-3

Arithmetic Flags

The arithmetic flags are assessed by the processor following the execution of any math, logical, or move instruction. The state of these bits remains in effect until the next math, logical, or move instruction in the program is executed.

Carry Flag


S:0/0 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) if a mathematical carry or borrow is generated.

Otherwise the bit remains cleared (0). When a STI, High-Speed Counter,

Event Interrupt, or User Fault Routine interrupts normal execution of your program, the original value of S:0/0 is restored when execution resumes.

OverFlow Flag


S:0/1 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) when the result of a mathematical operation does not fit in the destination. Otherwise the bit remains cleared (0). Whenever this bit is set (1), the overflow trap bit S:5/0 is also set (1). When an STI,

High-Speed Counter, Event Interrupt, or User Fault Routine interrupts normal execution of your program, the original value of S:0/1 is restored when execution resumes.

Zero Flag


S:0/2 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) when the result of a mathematical operation or data handling instruction is zero. Otherwise the bit remains cleared (0). When an STI, High-Speed Counter, Event Interrupt, or User Fault Routine interrupts normal execution of your program, the original value of S:0/2 is restored when execution resumes.

Sign Flag


S:0/3 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) when the result of a mathematical operation or data handling instruction is negative. Otherwise the bit remains cleared (0).

When a STI, High-Speed Counter, Event Interrupt, or User Fault Routine interrupts normal execution of your program, the original value of S:0/3 is restored when execution resumes.



Controller Mode

User Application Mode


S:1/0 to S:1/4 binary

Range Type

0 to 1 1110 status

Bits 0 through 4 function as follows:

S:1/0 to S:1/4

S:1/4 S:1/3 S:1/2 S:1/1 S:1/0

0

0

0

1

1

1

0

0

0

1

0

0

0

0

0

1

0

0

1

1

0

0

0

1

1

0

0

0

0

1

0

0

1

1

1

0

0

0

1

1

0

1

1

0

1

0

0

1

1

0

0

1

3

6

7

8

Mode

ID

Controller Mode

16

17

27

30 remote download in progress remote program mode remote suspend mode

(operation halted by execution of the SUS instruction) remote run mode remote test continuous mode remote test single scan mode download in progress program mode suspend mode

(operation halted by execution of the SUS instruction) run mode

(1) Valid modes are indicated by the (

•

) symbol. N/A indicates an invalid mode for that controller.

•

•

•

N/A

N/A

N/A


read only

Use by MicroLogix Controller

(1)

1200

•

•

•

1500

•

•

•

N/A

•

•

•

•

•

•

•

Forces Enabled


S:1/5 binary

Range

1

Type

status


read only

This bit is always set (1) by the controller to indicate that forces are enabled.

Forces Installed


S:1/6 binary

Range

0 or 1

Type

status


read only

This bit is set (1) by the controller to indicate that 1 or more inputs or outputs are forced. When this bit is clear, a force condition is not present within the controller.



Fault Override At Power-Up


S:1/8 binary 0 or 1

Type

control


read only

When set (1), causes the controller to clear the Major Error Halted bit (S:1/

13) at power-up. The power-up mode is determined by the controller mode switch (MicroLogix 1500 only) and the Power-Up Mode Behavior

Selection bit (S:1/12).

See also: FO - Fault Override on page 3-7.

Startup Protection Fault


S:1/9 binary

Range

0 or 1

Type

control


read only

When set (1) and the controller powers up in the RUN or REM RUN mode, the controller executes the User Fault Routine prior to the execution of the first scan of your program. You have the option of clearing the Major Error Halted bit (S:1/13) to resume operation. If the

User Fault Routine does not clear bit S:1/13, the controller faults and does not enter an executing mode. Program the User Fault Routine logic accordingly.

NOTE

When executing the startup protection fault routine, S:6

(major error fault code) contains the value 0016H.

Load Memory Module On Error Or Default Program


S:1/10 binary

Range

0 or 1

Type

control


read only

For this option to work, you must set (1) this bit in the control program before downloading the program to a memory module. When this bit it set in the memory module and power is applied, the controller downloads the memory module program when the control program is corrupt or a default program exists in the controller

.

NOTE

If you clear the controller memory, the controller loads the default program.

The mode of the controller after the transfer takes place is determined by the controller mode switch (MicroLogix 1500 only) and the Power-Up

Mode Behavior Selection bit (S:1/12).

See also: LE - Load on Error on pa ge3-8.



Load Memory Module Always


S:1/11 binary

Range

0 or 1

Type

control


read only

For this option to work, you must set (1) this bit in the control program before downloading the program to a memory module. When this bit is set in the memory module and power is applied, the controller downloads the memory module program.

The mode of the controller after the transfer takes place is determined by the controller mode switch (MicroLogix 1500 only) and the Power-Up

Mode Behavior Selection bit (S:1/12).

See also: LA - Load Always on page 3-8.

Power-Up Mode Behavior


S:1/12 binary

Range

0 or 1

Type

control


read only

If Power-Up Mode Behavior is clear (0 = Last State), the mode at power-up is dependent upon the:

• position of the mode switch (MicroLogix 1500 only)

• state of the Major Error Halted flag (S:1/13)

• mode at the previous power down

If Power Up Mode Behavior is set (1 = Run), the mode at power-up is dependent upon the:

• position of the mode switch (MicroLogix 1500 only)

• state of the Major Error Halted flag (S:1/13)

IMPORTANT

If you want the controller to power-up and enter the Run mode, regardless of any previous fault conditions, you must also set the Fault Override bit (S:1/8) so that the

Major Error Halted flag is cleared before determining the power up mode.



The following table shows the Power-Up Mode under various conditions

MicroLogix 1200

Remote

Major Error

Halted

False

MicroLogix 1500 -

Mode Switch Position at Power-Up

Program

True

Major Error

Halted

False

True

Remote

False

Power-Up

Mode Behavior

Last State

Run

Don’t Care

Power-Up

Mode Behavior

Don’t Care

Run

Don’t Care

Last State

Mode at Last Power-Down

REM Download, Download, REM Program,

Program or Any Test mode

REM Suspend or Suspend

REM Run or Run

Don’t Care

Don’t Care

Mode at Last Power-Down

Don’t Care

Power-Up Mode

REM Program

REM Suspend

REM Run

REM Run

REM Program w/Fault

Power-Up Mode

Program

Program w/Fault

REM Program

Run

True

False

Last State REM Download, Download, REM Program,

Program or Any Test mode

REM Suspend or Suspend REM Suspend

REM Run or Run

Don’t Care

Don’t Care

REM Run

REM Run

REM Program w/Fault

REM Suspend or Suspend Suspend

Any Mode except REM Suspend or Suspend Run

Run Don’t Care Run

True Don’t Care Don’t Care

Run w/Fault

(1)

(1) Run w/Fault is a fault condition, just as if the controller were in the Program /w Fault mode (outputs are reset and the controller program is not being executed). However, the controller enters Run mode as soon as the Major Error Halted flag is cleared.

See also: MB - Mode Behavior on page 3-8.




Major Error Halted


S:1/13 binary

Range

0 or 1

Type

status


read/write

The controller sets (1) this bit when a major error is encountered. The controller enters a fault condition and word S:6 contains the Fault Code that can be used to diagnose the condition. Any time bit S:1/13 is set, the controller:

• turns all outputs off and flashes the FAULT LED,

• or, enters the User Fault Routine allowing the control program to attempt recovery from the fault condition. If the User Fault Routine is able to clear S:1/13 and the fault condition, the controller continues to execute the control program. If the fault cannot be cleared, the outputs are cleared and the controller exits its executing mode and the FAULT LED flashes.

ATTENTION

!

If you clear the Major Error Halted bit (S:1/13) when the controller mode switch (MicroLogix 1500 only) is in the

RUN position, the controller immediately enters the RUN mode.

Future Access (OEM Lock)


S:1/14 binary

Range

0 or 1

Type

status


read only

When this bit is set (1), it indicates that the programming device must have an exact copy of the controller program.

See Allow Future Access Setting (OEM Lock) on page 2-10 for more

information.

First Scan Bit


S:1/15 binary

Range

0 or 1

Type

status


read/write

.

When the controller sets (1) this bit, it indicates that the first scan of the user program is in progress (following entry into an executing mode). The controller clears this bit after the first scan.

NOTE

The First Scan bit (S:1/15) is set during execution of the start-up protection fault routine. Refer to S:1/9 for more information.


STI Mode

STI Pending

Address

(1)

S:2/0

Data Format

binary

Range

0 or 1

Type

status


read only

(1) This bit can only be accessed via ladder logic. It cannot be accessed via communications (such as a Message instruction from another device).

This address is duplicated at STI:0/UIP. See Using the Selectable Timed

Interrupt (STI) Function File on page 18-12 for more information.

STI Enabled

Address

(1)

S:2/1

Data Format

binary

Range

0 or 1

Type

control


read/write


This address is duplicated at STI:0/TIE. See Using the Selectable Timed


STI Executing

Address

(1)

S:2/2

Data Format

binary

Range

0 or 1

Type

control


read only


This address is duplicated at STI:0/UIX. See Using the Selectable Timed


Memory Module Program Compare


S:2/9 binary

Range

0 or 1

Type

control


read only

When this bit is set (1) in the controller, its user program and the memory module user program must match for the controller to enter an executing mode.

If the user program does not match the memory module program, or if the memory module is not present, the controller faults with error code

0017H on any attempt to enter an executing mode.

An RTC module does not support program compare. If program compare is enabled and an RTC-only module is installed, the controller does not enter an executing mode.

See also: LPC - Load Program Compare on page 3-7.




Math Overflow Selection


S:2/14 binary

Range

0 or 1

Type

control


read/write

Set (1) this bit when you intend to use 32-bit addition and subtraction.

When S:2/14 is set, and the result of an ADD, SUB, MUL, or DIV instruction cannot be represented in the destination address (underflow or overflow),

• the overflow bit S:0/1 is set,

• the overflow trap bit S:5/0 is set,

• and the destination address contains the unsigned truncated least significant 16 or 32 bits of the result.

The default condition of S:2/14 is cleared (0). When S:2/14 is cleared (0), and the result of an ADD, SUB, MUL, or DIV instruction cannot be represented in the destination address (underflow or overflow),

• the overflow bit S:0/1 is set,

• the overflow trap bit S:5/0 is set,

• the destination address contains +32,767 (word) or +2,147,483,647

(long word) if the result is positive; or -32,768 (word) or

-2,147,483,648 (long word) if the result is negative.

To provide protection from inadvertent alteration of your selection, program an unconditional OTL instruction at address S:2/14 to ensure the new math overflow operation. Program an unconditional OTU instruction at address S:2/14 to ensure the original math overflow operation.

Watchdog Scan Time


S:3H Byte

Range

2 to 255

Type

control


read/write

This byte value contains the number of 10 ms intervals allowed to occur during a program cycle. The timing accuracy is from -10 ms to +0 ms. This means that a value of 2 results in a timeout between 10 and 20 ms.

If the program scan time value equals the watchdog value, a watchdog major error is generated (code 0022H).

Free Running Clock


S:4 binary

Range

0 to FFFF

Type

status


read/write

This register contains a free running counter that is incremented every 100

µs. This word is cleared (0) upon entering an executing mode.


Minor Error Bits

Overflow Trap Bit


S:5/0 binary

Range

0 or 1

Type

status


read/write

If this bit is ever set (1) upon execution of the END or TND instruction, a major error (0020H) is generated. To avoid this type of major error from occurring, examine the state of this bit following a math instruction (ADD,

SUB, MUL, DIV, NEG, SCL, TOD, or FRD), take appropriate action, and then clear bit S:5/0 using an OTU instruction with S:5/0.

Control Register Error


S:5/2 binary

Range

0 or 1

Type

status


read/write

The LFU, LFL, FFU, FFL, BSL, BSR, SQO, SQC, and SQL instructions are capable of generating this error. When bit S:5/2 is set (1), it indicates that the error bit of a control word used by the instruction has been set.

If this bit is ever set upon execution of the END or TND instruction, major error (0020H) is generated. To avoid this type of major error from occurring, examine the state of this bit following a control register instruction, take appropriate action, and then clear bit S:5/2 using an OTU instruction with S:5/2.

Major Error Detected in User Fault Routine


S:5/3 binary

Range

0 or 1

Type

status


read/write

When set (1), the major error code (S:6) represents the major error that occurred while processing the User Fault Routine due to another major error.




Memory Module Boot


S:5/8 binary

Range

0 or 1

Type

status


read/write

When this bit is set (1) by the controller, it indicates that a memory module program has been transferred due to S:1/10 (Load Memory

Module on Error or Default Program) or S:1/11 (Load Memory Module

Always) being set in an attached memory module user program. This bit is not cleared (0) by the controller.

Your program can examine the state of this bit on the first scan (using bit

S:1/15) on entry into an Executing mode to determine if the memory module user program has been transferred after a power-up occurred.

This information is useful when you have an application that contains retentive data and a memory module has bit S:1/10 or bit S:1/11 set.

Memory Module Password Mismatch


S:5/9 binary

Range

0 or 1

Type

status


read/write

At power-up, if Load Always is set, and the controller and memory module passwords do not match, the Memory Module Password

Mismatch bit is set (1).

See Password Protection on pag e2-9 for more information.

STI Lost

Address

(1)

S:5/10

Data Format

binary

Range

0 or 1

Type

status


read/write


This address is duplicated at STI:0/UIL. SeeUsing the Selectable Timed


Retentive Data Lost (MicroLogix 1200 only)


S:5/11 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) whenever retentive data is lost. This bit remains set until you clear (0) it. The controller validates retentive data at power up. If user data is invalid, the controller sets the Retentive Data Lost indicator. The data in the controller are the values that were in the program when the program was last transferred to the controller. If the Retentive Data Lost bit is set, a fault occurs when entering an executing mode, but only if the

Fault Override bit (S:1/8) is not set.


Processor Battery Low (MicroLogix 1500 only)


S:5/11 binary

Range

0 or 1

Type

status


read only

This bit is set (1) when the battery is low.

IMPORTANT

Install a replacement battery immediately. See your hardware manual for more information.

See also: RTC Battery Operation on page 3-4.

Input Filter Selection Modified


S:5/13 binary

Range

0 or 1

Type

status


read/write

This bit is set (1) whenever the discrete input filter selection in the control program is not compatible with the hardware.

ASCII String Manipulation Error


S:5/15 binary

Range

0 or 1

Type

status


read

This bit is set (1) whenever an invalid string length occurs. When S:5/15 is set, the Invalid String Length Error (1F39H) is written to the Major Error

Fault Code word (S:6).

This bit applies to the MicroLogix 1200 and 1500 Series B Controllers.

Major Error Code


S:6 word

Range

0 to FFFF

Type

status


read/write

This register displays a value which can be used to determine what

caused a fault to occur. See Identifying Controller Faults on page D-1 to

learn more about troubleshooting faults.



Suspend Code


S:7 word

Range

-32,768 to

+32,767

Type

status


read/write

When the controller executes an Suspend (SUS) instruction, the SUS code is written to this location, S:7. This pinpoints the conditions in the application that caused the Suspend mode. The controller does not clear this value.

Use the SUS instruction with startup troubleshooting, or as runtime diagnostics for detection of system errors.

Suspend File


S:8 word

Range

0 to 255

Type

status


read/write

When the controller executes an Suspend (SUS) instruction, the SUS file is written to this location, S:8. This pinpoints the conditions in the application that caused the Suspend mode. The controller does not clear this value.

Use the SUS instruction with startup troubleshooting, or as runtime diagnostics for detection of system errors.

Active Nodes (Nodes 0 to 15)

Address

(1)

S:9

Data Format

word

Range

0 to FFFF

Type

status


read only


This address is duplicated in the Communications Status File (CSx:0.27).

See Active Node Table Block on page 3-17 for more information.

Active Nodes (Nodes 16 to 31)

Address

(1)

S:10

Data Format

word

Range

0 to FFFF

Type

status


read only


This address is duplicated in the Communications Status File (CSx:0.28).

See Active Node Table Block on page 3-17 for more information.



Math Register


S:13

(low byte) word

S:14

(high byte) word

Range

-32,768 to

+32,767

-32,768 to

+32,767

Type

status status


read/write read/write

These two words are used in conjunction with the MUL, DIV, FRD, and

TOD math instructions. The math register value is assessed upon execution of the instruction and remains valid until the next MUL, DIV,

FRD, or TOD instruction is executed in the user program.

Node Address

Address

(1)

S:15 (low byte)

Data Format

byte

Range

0 to 255


status read only

(1) This byte can only be accessed via ladder logic. It cannot be accessed via communications (such as a Message instruction from another device).

This address is duplicated in the Communications Status File (CSx:0.5/0

through CSx:0.5/7). See General Channel Status Block on page 3-14 for

more information.

Baud Rate

Address

(1)

S:15 (high byte)

Data Format

byte

Range

0 to 255


status read only

(1) This byte can only be accessed via ladder logic. It cannot be accessed via communications (such as a Message instruction from another device).

This address is duplicated in the Communications Status File (CSx:0.5/8

through CSx:0.5/15). See General Channel Status Block on page 3-14 for

more information.

Maximum Scan Time


S:22 word

Range

0 to 32,767

Type

status


read/write

This word indicates the maximum observed interval between consecutive program scans.

The controller compares each scan value to the value contained in S:22. If a scan value is larger than the previous, the larger value is stored in S:22.

This value indicates, in 100 us increments, the time elapsed in the longest program cycle of the controller. Resolution is -100 µs to +0 µs. For example, the value 9 indicates that 800 to 900 us was observed as the longest program cycle.




User Fault Routine File Number


S:29 word

Range

0 to 255

Type

status


read only

This register is used to control which subroutine executes when a User

Fault is generated.

STI Set Point

Address

(1)

S:30

Data Format

word

Range

0 to 65535

Type

status


read only


This address is duplicated at STI:0/SPM. SeeUsing the Selectable Timed


STI File Number

Address

(1)

S:31

Data Format

word

Range

0 to 65535

Type

status


read only


This address is duplicated at STI:0/PFN. SeeUsing the Selectable Timed


Channel 0 Communications

Incoming Command Pending

Address

(1)

S:33/0

Data Format

binary

Range

0 or 1

Type

status


read only


This address is duplicated in the Communications Status File at CS0:0.4/0.

See General Channel Status Block on page 3-14 for more information.

Message Reply Pending

Address

(1)

S:33/1

Data Format

binary

Range

0 or 1

Type

status


read only





Outgoing Message Command Pending

Address

(1)

S:33/2

Data Format

binary

Range

0 or 1

Type

status


read only




Communications Mode Selection

Address

(1)

S:33/3

Data Format

binary

Range

0 or 1

Type

status


read only




Communications Active

Address

(1)

S:33/4

Data Format

binary

Range

0 or 1

Type

status


read only




Scan Toggle Bit


S:33/9 binary

Range

0 or 1

Type

status


read/write

The controller changes the status of this bit at the end of each scan. It is reset upon entry into an executing mode.

Last 100 µSec Scan Time


S:35 word

Range

0 to 32,767

Type

status


read/write

This register indicates the elapsed time for the last program cycle of the controller (in 100 µs increments).



Data File Overwrite Protection Lost


S:36/10 binary

Range

0 or 1

Type

status


read/write

When clear (0), this bit indicates that at the time of the last program transfer to the controller, protected data files in the controller were not overwritten, or there were no protected data files in the program being downloaded.

When set (1), this bit indicates that data has been overwritten. See User

Program Transfer Requirements on page 2-7 for more information.

See Setting Download File Protection on pag e2-6 for more information.

RTC Year

Address

(1)

S:37

Data Format

word

Range Type

1998 to 2097 status


read only


This address is duplicated in the Real-Time Clock Function File at

RTC:0.YR

.

See Real-Time Clock Function File on page 3-3 for more

information.

RTC Month

Address

(1)

S:38

Data Format

word

Range

1 to 12

Type

status


read only



RTC:0.MON

.


information.

RTC Day of Month

Address

(1)

S:39

Data Format

word

Range

1 to 31

Type

status


read only



RTC:0.DAY

.


information.



RTC Hours

Address

(1)

S:40

Data Format

word

Range

0 to 23

Type

status


read only

(1) This word can only be accessed via ladder logic. It cannot be accessed via communications (such as a Message instruction from another device).


RTC:0.HR

.


information.

RTC Minutes

Address

(1)

S:41

Data Format

word

Range

0 to 59

Type

status


read only



RTC:0.MIN

.


information.

RTC Seconds

Address

(1)

S:42

Data Format

word

Range

0 to 59

Type

status


read only



RTC:0.SEC

.


information.

RTC Day of Week

Address

(1)

S:53

Data Format

word

Range

0 to 6

Type

status


read only



RTC:0.DOW

.


information.



OS Catalog Number


S:57 word

Range

0 to 32,767

Type

status


read only

This register identifies the Catalog Number for the Operating System in the controller.

OS Series


S:58 ASCII

Range

A to Z

Type

status


read only

This register identifies the Series letter for the Operating System in the controller.

OS FRN


S:59 word

Range

0 to 32,767

Type

status


read only

This register identifies the FRN of the Operating System in the controller.

Processor Catalog Number


S:60 ASCII

Range

“A” to “ZZ”

Type

status


read only

This register identifies the Catalog Number for the processor.

Processor Series


S:61 ASCII

Range

A to Z

Type

status

This register identifies the Series of the processor.


read only

Processor Revision


S:62 word

Range

0 to 32,767

Type

status


read only

This register identifies the revision (Boot FRN) of the processor.



User Program Functionality Type


S:63 word

Range

0 to 32,767

Type

status


read only

This register identifies the level of functionality of the user program in the controller.

Compiler Revision - Build Number


S:64 (low byte) byte

Range

0 to 255

Type

status


read only

This register identifies the Build Number of the compiler which created the program in the controller.

Compiler Revision - Release


S:64 (high byte) byte

Range

0 to 255

Type

status


read only

This register identifies the Release of the compiler which created the program in the controller.




1

Appendix

D

Fault Messages and Error Codes

This chapter describes how to troubleshoot your controller. Topics include:

• identifying controller faults

• contacting Rockwell Automation for assistance

Identifying Controller

Faults

While a program is executing, a fault may occur within the operating system or your program. When a fault occurs, you have various options to determine what the fault is and how to correct it. This section describes how to clear faults and provides a list of possible advisory messages with recommended corrective actions.

Automatically Clearing Faults

You can automatically clear a fault by cycling power to the controller when the Fault Override at Power-Up bit (S:1/8) is set in the status file.

You can also configure the controller to clear faults and go to RUN every time the controller is power cycled. This is a feature that OEMs can build into their equipment to allow end users to reset the controller. If the controller faults, it can be reset by simply cycling power to the machine.

To accomplish this, set the following bits in the status file:

•

S2:1/8 - Fault Override at Power-up

•

S2:1/12 - Mode Behavior

If the fault condition still exists after cycling power, the controller

re-enters the fault mode. For more information on status bits, see System

Status File on page C-1.

NOTE

You can declare your own application-specific major fault by writing your own unique value to S:6 and then setting bit S:1/13 to prevent reusing system defined codes. The recommended values for user-defined faults are FF00 to

FF0F.


D-2 Fault Messages and Error Codes

Manually Clearing Faults Using the Fault Routine

The occurrence of recoverable or non-recoverable user faults can cause the user fault subroutine to be executed. If the fault is recoverable, the subroutine can be used to correct the problem and clear the fault bit S:1/

13. The controller then continues in the Run or test mode.

The subroutine does not execute for non-user faults. See User Fault

Routine on page 18-6 for information on creating a user fault subroutine.

Fault Messages

Error

Code

(Hex)

0001

0002

0003

0004

0005

This section contains fault messages that can occur during operation of the MicroLogix 1200 and MicroLogix 1500 programmable controllers. Each table lists the error code description, the probable cause, and the recommended corrective action.

Advisory Message Description Fault

Classification


NVRAM ERROR The default program is loaded to the

•

• controller memory. This occurs:

• if a power down occurred during program download or transfer from the memory module.

RAM integrity test failed.

FLASH integrity test failed

(MicroLogix 1200 only).

UNEXPECTED RESET

•

The controller was unexpectedly reset due to a noisy environment or internal hardware failure.

•

The default program is loaded.

(MicroLogix 1500 only)

•

Retentive Data is lost. See page

C-12. (MicroLogix 1200 only)

Non-User

Non-User

Non-User MEMORY MODULE

USER PROGRAM IS

CORRUPT

MEMORY INTEGRITY

ERROR

Memory module memory error. This error can also occur when going to the Run mode.

While the controller was powered up, ROM or RAM became corrupt.

Non-User

RETENTIVE DATA IS

LOST (MicroLogix

1200 only)

Retentive Data is lost. See page

C-12.

Recoverable

•

•

Re-download or transfer the program.

Verify battery is connected (MicroLogix

1500 only).

•

Contact your local Rockwell Automation representative if the error persists.

•

Refer to proper grounding guidelines and using surge suppressors in your controller’s

User Manual.

•

Verify battery is connected (MicroLogix

1500 only).

•


Re-program the memory module. If the error persists, replace the memory module.

•

Cycle power on your unit. Then, re-download your program and start up your system.

•


User Manual.

•




Fault Messages and Error Codes D-3

Error

Code

(Hex)

0006

0007

0008

0009

000A

000B

0011

0012

0015

Advisory Message

MEMORY MODULE

HARDWARE FAULT

MEMORY MODULE

TRANSFER ERROR

FATAL INTERNAL

SOFTWARE ERROR

FATAL INTERNAL

HARDWARE ERROR

OS MISSING OR

CORRUPT

BASE HARDWARE

FAULT

EXECUTABLE FILE 2 IS

MISSING

LADDER PROGRAM

ERROR

I/O CONFIGURATION

FILE ERROR

Description

The memory module hardware faulted or the memory module is incompatible with OS.

Failure during memory module transfer.

An unexpected software error occurred.

An unexpected hardware error occurred.

The operating system required for the user program is corrupt or missing.

The base hardware faulted or is incompatible with the OS.

Ladder File 2 is missing from the program.

The ladder program has a memory integrity problem.

The user program I/O configuration is invalid.

Fault

Classification


Non-User

Non-User

Non-User

Non-User

Non-User

Non-User

Non-User

Non-User

Non-User

•

•

Upgrade the OS to be compatible with memory module.

Obtain a new memory module.

•

•

•

•

•

•

•

•

Re-attempt the transfer. If the error persists, replace the memory module.

•

Cycle power on your unit. Then, re-download your program and re-initialize any necessary data.

Start up your system.


User Manual.

•


•

Cycle power on your unit. Then, re-download your program and re-initialize any necessary data.

Start up your system.


User Manual.

•


Download a new OS using ControlFlash.

Contact your local Rockwell Automation representative for more information about available operating systems your controller.

•

•

Upgrade the OS using ControlFlash.

Replace the Controller (MicroLogix 1200

only).

Replace the Base Unit (MicroLogix 1500

only).


•

Re-compile and reload the program.

•

•

Reload the program or re-compile and reload the program. If the error persists, be sure to use RSI programming software to develop and load the program.


User Manual.

Re-compile and reload the program, and enter the Run mode. If the error persists, be sure to use RSI programming software to develop and load the program.



Error

Code

(Hex)

0016

0017

0018

001A

0020

0021

0022

0023


Classification


STARTUP

PROTECTION FAULT

The user fault routine was executed at power-up, prior to the main ladder program. Bit S:1/13 (Major Error

Halted) was not cleared at the end of the User Fault Routine. The User

Fault Routine ran because bit S:1/9 was set at power-up.

Recoverable

•

Either reset bit S:1/9 if this is consistent with the application requirements, and change the mode back to RUN, or

• clear S:1/13, the Major Error Halted bit, before the end of the User Fault Routine.

NVRAM/MEMORY

MODULE USER

PROGRAM

MISMATCH

Bit S:2/9 is set in the controller and the memory module user program does not match the controller user program.

Non-Recoverable Transfer the memory module program to the controller and then change to Run mode.

MEMORY MODULE

USER PROGRAM

INCOMPATIBLE WITH

OS

USER PROGRAM

INCOMPATIBLE WITH

OS AT POWER-UP

MINOR ERROR AT

END-OF-SCAN

DETECTED

IMPORTANT

The user program in the memory module is incompatible with the OS.

The user program is incompatible with the OS.

A minor fault bit (bits 0-7) in S:5 was set at the end of scan.

Non-User

Non-User

Recoverable

•

Upgrade the OS using ControlFlash to be compatible with the memory module.

•

•

Obtain a new memory module.


•

•

Upgrade the OS using ControlFlash.


•

Correct the instruction logic causing the error.

•

Enter the status file display in your programming software and clear the fault.

•

Enter the Run mode.

Re-apply power to the expansion I/O bank.

See Important note below.

EXPANSION POWER

FAIL (EPF)


A power failure is present on the expansion I/O bank.

This error code is present only when the controller is powered, and power is not applied to the expansion I/O bank. This is a self-clearing error code. When power is re-applied to the expansion I/O bank, the fault is cleared. See Important note below.

Non-User

WATCHDOG TIMER

EXPIRED, SEE S:3

If this fault occurs while the system is in the RUN mode, the controller faults. When expansion I/O power is restored, the controller clears the fault and re-enters the RUN mode.

If you change the mode switch while this fault is present, the controller may not re-enter the RUN mode when expansion I/O power is restored.

If an EPF condition is present and expansion I/O power is OK, toggle the mode switch to PROGRAM and then to RUN. The fault should clear and the controller enters the RUN mode.

The program scan time exceeded the watchdog timeout value (S:3H).

Non-Recoverable

•

Determine if the program is caught in a loop and correct the problem.

•

Increase the watchdog timeout value in the status file.

STI ERROR An error occurred in the STI configuration.

Recoverable See the Error Code in the STI Function File for the specific error.



0036

0037

003B

003C

Error

Code

(Hex)

0028

0029

002E

0030

0031

0032

0033

0034

0035


Classification


INVALID OR

NONEXISTENT USER

FAULT ROUTINE

VALUE

INSTRUCTION

INDIRECTION

OUTSIDE OF DATA

SPACE

•

A fault routine number was entered in the status file, number

(S:29), but either the fault routine was not physically created, or

• the fault routine number was less than 3 or greater than 255.

An indirect address reference in the ladder program is outside of the entire data file space.

Non-User

Recoverable

EII ERROR An error occurred in the EII configuration.

Recoverable See the Error Code in the EII Function File for the specific error.

SUBROUTINE

NESTING EXCEEDS

LIMIT

UNSUPPORTED

INSTRUCTION

DETECTED

SQO/SQC/SQL

OUTSIDE OF DATA

FILE SPACE

BSL/BSR/FFL/FFU/LFL/

LFU CROSSED DATA

FILE SPACE

NEGATIVE VALUE IN

TIMER PRESET OR

ACCUMULATOR

ILLEGAL

INSTRUCTION IN

INTERRUPT FILE

The JSR instruction nesting level exceeded the controller memory space.

The program contains an instruction(s) that is not supported by the controller.

A sequencer instruction length/ position parameter references outside of the entire data file space.

The length/position parameter of a

BSL, BSR, FFL, FFU, LFL, or LFU instruction references outside of the entire data file space.

Non-User

Non-User

Recoverable

Recoverable

Correct the user program to reduce the nesting levels used and to meet the restrictions for the JSR instruction. Then reload the program and Run.

•

Modify the program so that all instructions are supported by the controller.

•

Re-compile and reload the program and enter the Run mode.

•

Correct the program to ensure that the length and position parameters do not point outside data file space.

•

Re-compile, reload the program and enter the Run mode.

•

•

Correct the program to ensure that the length and position parameters do not point outside of the data space.


A negative value was loaded to a timer preset or accumulator.

The program contains a Temporary

End (TND), Refresh (REF), or Service

Communication instruction in an interrupt subroutine (STI, EII, HSC) or user fault routine.

Recoverable

•

If the program is moving values to the accumulated or preset word of a timer, make certain these values are not negative.

•

Reload the program and enter the Run mode.

Non-Recoverable

•

Correct the program.

•


Recoverable

•

•

Either clear the fault routine file number

(S:29) in the status file, or create a fault routine for the file number reference in the status file (S:29). The file number must be greater than 2 and less than 256.

Correct the program to ensure that there are no indirect references outside data file space.

Re-compile, reload the program and enter the

Run mode.

INVALID PID

PARAMETER

HSC ERROR

PTO ERROR

PWM ERROR

An invalid value is being used for a

PID instruction parameter.

An error occurred in the HSC configuration.

An error occurred in the PTO instruction configuration.

An error occurred in the PWM instruction configuration.

Recoverable

Recoverable or

Non-User

Recoverable or

Non-User

See page 19-1, Process Control Instruction for

more information about the PID instruction.

See the Error Code in the HSC Function File for the specific error.

See the Error Code in the PTO Function File for the specific error.

See the Error Code in the PWM Function File for the specific error.



Error

Code

(Hex)

003D


Classification


003E

003F

0050

0051

0052

0070 xx71

(1) xx79

(1)

0080 xx81

(1)

INVALID SEQUENCER

LENGTH/POSITION

A sequencer instruction (SQO, SQC,

SQL) length/position parameter is greater than 255.

Recoverable Correct the user program, then re-compile, reload the program and enter the Run mode.

INVALID BIT SHIFT OR

LIFO/FIFO

PARAMETER

COP/FLL OUTSIDE OF

DATA FILE SPACE

CONTROLLER TYPE

MISMATCH

BASE TYPE

MISMATCH

MINIMUM SERIES

ERROR

EXPANSION I/O

TERMINATOR

REMOVED


EXPANSION I/O

HARDWARE ERROR

EXPANSION I/O

MODULE ERROR

EXPANSION I/O

TERMINATOR

REMOVED


A BSR or BSL instruction length parameter is greater than 2048 or an

FFU, FFL, LFU, LFL instruction length parameter is greater than 128 (word file) or greater than 64 (double word file)

Recoverable Correct the user program or allocate more data file space using the memory map, then reload and Run.

A COP or FLL instruction length parameter references outside of the entire data space.

A particular controller type was selected in the user program configuration, but did not match the actual controller type.

The required expansion I/O terminator was removed.

Recoverable

Non-User

Non-User

•

Correct the program to ensure that the length and parameter do not point outside of the data file space.

•


•

Connect to the hardware that is specified in the user program, or

•

Reconfigure the program to match the attached hardware.

A particular hardware type (AWA,

BWA, BXB) was selected in the user program configuration, but did no match the actual base.

The hardware minimum series selected in the user program configuration was greater than the series on the actual hardware.

The required expansion I/O terminator was removed.

The controller cannot communicate with an expansion I/O module.

An expansion I/O module generated an error.

Non-User

•


•


Non-User

•


•


Non-Recoverable

•

Check the expansion I/O terminator on the last

I/O module.

•

Cycle power.

Non-Recoverable

•

Check connections.

•

Check for a noise problem and be sure proper grounding practices are used.

•

•

Replace the module.

Cycle power.

Non-Recoverable

•

•

Refer to the I/O Module Status (IOS) file.

Consult the documentation for your specific I/O module to determine possible causes of a module error.

•

Check expansion I/O terminator on last I/O module.

•

Cycle power.

EXPANSION I/O

HARDWARE ERROR

The controller cannot communicate with an expansion I/O module.

Non-User

•

•

•

•

Check connections.

Check for a noise problem and be sure proper grounding practices are used.

Replace the module.

Cycle power.



Error

Code

(Hex)

0083

0084

0085

xx86 xx87 xx88 xx89

(1)

(1)

(1)

(1)(2)

xx8A

(1)(2)


MAX I/O CABLES

EXCEEDED

MAX I/O POWER

SUPPLIES EXCEEDED

MAX I/O MODULES

EXCEEDED

EXPANSION I/O

MODULE BAUD RATE

ERROR

I/O CONFIGURATION

MISMATCH

EXPANSION I/O

MODULE

CONFIGURATION

ERROR

EXPANSION I/O

MODULE ERROR

EXPANSION I/O

CABLE

CONFIGURATION

MISMATCH ERROR

Description

The maximum number of expansion

I/O cables allowed was exceeded.

Fault

Classification


Non-User


I/O power supplies allowed was exceeded.

Non-User


I/O modules allowed was exceeded.

Non-User

An expansion I/O module could not communicate at the baud rate specified in the user program I/O configuration.

Non-User

•

The expansion I/O configuration in the user program did not match the actual configuration, or

•

The expansion I/O configuration in the user program specified a module, but one was not found, or

•

The expansion I/O module configuration data size for a module was greater than what the module is capable of holding.

Non-User

The number of input or output image words configured in the user program exceeds the image size in the expansion I/O module.

Non-User

An expansion I/O module generated an error.

•

Either an expansion I/O cable is configured in the user program, but no cable is present, or

• an expansion I/O cable is configured in the user program and a cable is physically present, but the types do not match.

Non-User

Non-User

•

•

•

Reconfigure the expansion I/O system so that it has an allowable number of cables.

Cycle power.

Reconfigure the expansion I/O system so that it has the correct number of power supplies.

•

Reconfigure the expansion I/O system so that it has an allowable number of modules.

Cycle power.

•

•

•

•

Change the baud rate in the user program

I/O configuration, and

Re-compile, reload the program and enter the Run mode, or

Replace the module.

•

•

•

Cycle power.

Either correct the user program I/O configuration to match the actual configuration, or

With power off, correct the actual I/O configuration to match the user program configuration.

•

•

Correct the user program I/O configuration to reduce the number of input or output words, and


•

•

Refer to the I/O status file.

Consult the documentation for your specific I/O module to determine possible causes of a module error.

•

•

•

•

Correct the user program to eliminate a cable that is not present


Add the missing cable.

Cycle power.



Error

Code

(Hex)

xx8B xx8C

(1)(2)

(1)(2)

0x1F39


EXPANSION I/O

POWER SUPPLY

CONFIGURATION

MISMATCH ERROR

EXPANSION I/O

OBJECT TYPE

MISMATCH

INVALID STRING

LENGTH

(3)

Description Fault

Classification

•

Either an expansion I/O power supply is configured in the user program, but no power supply is present, or

• an expansion I/O power supply is configured in the user program and a power supply is physically present, but the types do not match.

Non-User

An expansion I/O object (i.e. cable, power supply, or module) in the user program I/O configuration is not the same object type as is physically present.

Non-User

The first word of string data contains a negative, zero, or value greater than 82.

Recoverable


•

Correct the user program to eliminate a power supply that is not present

•

•


With power removed, add the missing power supply.

•

Correct the user program I/O configuration so that the object types match the actual configuration, and

•

Re-compile, reload the program and enter the Run mode. Or

•

Correct the actual configuration to match the user program I/O configuration.

•

Cycle power.

Check the first word of the string data element for invalid values and correct the data.

(1) xx indicates module number. If xx = 0, problem cannot be traced to a specific module.

(2) The xx in this error code means that the error occurs at the location of the last properly configured Expansion I/O module +1. You should use this information in conjunction with the specific error code to determine the source of the problem.

(3) Applies to MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors.



Contacting Rockwell

Automation for

Assistance

If you need to contact Rockwell Automation or local distributor for assistance, it is helpful to obtain the following information ready:

• controller type, series letter, and revision letter of the base unit

• series letter, revision letter, and firmware (FRN) number of the processor (on bottom side of processor unit)

NOTE

You can also check the FRN by looking at word S:59

(Operating System FRN) in the Status File.

• controller LED status

• controller error codes (found in S2:6 of status file).

Rockwell Automation phone numbers are listed on the back cover of this manual.

To contact us via the Internet, go to http://www.rockwellautomation.com.




1

Appendix

E

Protocol Configuration

Use the information in this appendix for configuring communication protocols. The following protocols are supported from any RS-232 communication channel:

•

DH-485

•

DF1 Full-Duplex

•


•

Modbus™ RTU Slave

•

ASCII

This appendix is organized into the following sections:

•

DH-485 Communication Protocol on page E-2

•

DF1 Full-Duplex Protocol on page E-5

•

DF1 Half-Duplex Protocol on page E-6

•

Modbus™ RTU Slave Protocol (MicroLogix 1200 Controllers and

MicroLogix 1500 Series B and higher Processors only) on page E-9

•

ASCII Driver (MicroLogix 1200 and 1500 Series B and higher

Controllers only) on page E-13

See your controller’s User Manual for information about required network devices and accessories.


E-2 Protocol Configuration

DH-485 Communication

Protocol

The information in this section describes the DH-485 network functions, network architecture, and performance characteristics. It also helps you plan and operate the controller on a DH-485 network.

DH-485 Network Description

The DH-485 protocol defines the communication between multiple devices that coexist on a single pair of wires. DH-485 protocol uses

RS-485 Half-Duplex as its physical interface. (RS-485 is a definition of electrical characteristics; it is not a protocol.) RS-485 uses devices that are capable of co-existing on a common data circuit, thus allowing data to be easily shared between devices.

The DH-485 network offers:

• interconnection of 32 devices

• multi-master capability

• token passing access control

• the ability to add or remove nodes without disrupting the network

• maximum network length of 1219 m (4000 ft.)

The DH-485 protocol supports two classes of devices: initiators and responders. All initiators on the network get a chance to initiate message transfers. To determine which initiator has the right to transmit, a token passing algorithm is used.

The following section describes the protocol used to control message transfers on the DH-485 network.

DH-485 Token Rotation

A node holding the token can send a message onto the network. Each node is allowed a fixed number of transmissions (based on the Token

Hold Factor) each time it receives the token. After a node sends a message, it passes the token to the next device.

The allowable range of node addresses 0 to 31. There must be at least one initiator on the network (such as a MicroLogix controller, or an SLC 5/02 or higher processor).


Protocol Configuration E-3

DH-485 Configuration Parameters

When communications are configured for DH-485, the following parameters can be changed:

Table E.1:

Parameter

Baud Rate

Node Address

Token Hold Factor

Max Node Address

Options

9600, 19.2K

1 to 31 decimal

1 to 4

1 to 31

Programming Software Default

19.2K

1

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31

The major software issues you need to resolve before installing a network are discussed in the following sections.

Software Considerations

Software considerations include the configuration of the network and the parameters that can be set to the specific requirements of the network.

The following are major configuration factors that have a significant effect on network performance:

• number of nodes on the network

• addresses of those nodes

• baud rate

The following sections explain network considerations and describe ways to select parameters for optimum network performance (speed). Refer to your programming software’s documentation for more information.

Number of Nodes

The number of nodes on the network directly affects the data transfer time between nodes. Unnecessary nodes (such as a second programming terminal that is not being used) slow the data transfer rate. The maximum number of nodes on the network is 32.



Setting Node Addresses

The best network performance occurs when node addresses are assigned in sequential order. Initiators, such as personal computers, should be assigned the lowest numbered addresses to minimize the time required to initialize the network. The valid range for the MicroLogix controllers is 1 to 31 (controllers cannot be node 0). The default setting is 1. The node address is stored in the controller Communications Status file (CS0:5/0 to

CS0:5/7). Configure the node address via Channel Configuration using

RSLogix 500. Select the Channel 0 tab. The node address is listed as

Source ID.

Setting Controller Baud Rate

The best network performance occurs at the highest baud rate, which is

19200. This is the default baud rate for a MicroLogix devices on the

DH-485 network. All devices must be at the same baud rate. This rate is stored in the controller Communications Status file (CS0:5/8 to CS0:5/15).

Configure the baud rate via Channel Configuration using RSLogix 500.

Select the Channel 0 tab.

Setting Maximum Node Address

Once you have an established network set up, and are confident that you will not be adding more devices, you may enhance performance by adjusting the maximum node address of your controllers. It should be set to the highest node address being used.

IMPORTANT

All devices should be set to the same maximum node address.

MicroLogix 1200 and 1500 Remote Packet Support

These controllers can respond and initiate with device’s communications

(or commands) that do not originate on the local DH-485 network. This is useful in installations where communication is needed between the

DH-485 and DH+ networks.



DF1 Full-Duplex

Protocol

DF1 Full-Duplex protocol provides a point-to-point connection between two devices. DF1 Full-Duplex protocol combines data transparency

(American National Standards Institute ANSI - X3.28-1976 specification subcategory D1) and 2-way simultaneous transmission with embedded responses (subcategory F1).

The MicroLogix controllers support the DF1 Full-Duplex protocol via

RS-232 connection to external devices, such as computers, or other controllers that support DF1 Full-Duplex.

DF1 is an open protocol. Refer to DF1 Protocol and Command Set

Reference Manual, Allen-Bradley publication 1770-6.5.16, for more information.

DF1 Full-Duplex Operation

DF1 Full-Duplex protocol (also referred to as DF1 point-to-point protocol) is useful where RS-232 point-to-point communication is required. This type of protocol supports simultaneous transmissions between two devices in both directions. DF1 protocol controls message flow, detects and signals errors, and retries if errors are detected.

When the system driver is DF1 Full-Duplex, the following parameters can be changed:

Table E.2 DF1 Full-Duplex Configuration Parameters

Parameter Options

Baud Rate

Parity

Source ID (Node Address)

300, 600, 1200, 2400, 4800, 9600, 19.2K, 38.4K none, even

0 to 254 decimal

Control Line

Error Detection

Embedded Responses no handshaking, Full-Duplex modem

CRC, BCC auto detect, enabled

Duplicate Packet (Message) Detect enabled, disabled

ACK Timeout (x20 ms) 1 to 65535 counts (20 ms increments)

NAK retries 0 to 255

ENQ retries

Stop Bits

0 to 255 not a setting, always 1

Programming Software Default

19.2K

none

1 no handshaking

CRC auto detect enabled

50 counts

3 retries

3 retries

1



DF1 Half-Duplex

Protocol

DF1 Half-Duplex protocol provides a multi-drop single master/multiple slave network. DF1 Half-Duplex protocol supports data transparency

(American National Standards Institute ANSI - X3.28-1976 specification subcategory D1). In contrast to DF1 Full-Duplex, communication takes place in one direction at a time. You can use the RS-232 port on the

MicroLogix controller as both a Half-Duplex programming port, and a

Half-Duplex peer-to-peer messaging port.

DF1 Half-Duplex Operation

The master device initiates all communication by “polling” each slave device. The slave device may only transmit message packets when it is polled by the master. It is the master’s responsibility to poll each slave on a regular and sequential basis to allow slave devices an opportunity to communicate. During a polling sequence, the master polls a slave either repeatedly until the slave indicates that it has no more message packets to transmit or just one time per polling sequence, depending on how the master is configured.

An additional feature of the DF1 Half-Duplex protocol is that it is possible for a slave device to enable a MSG instruction in its ladder program to send or request data to/from another slave. When the initiating slave is polled, the MSG instruction is sent to the master. The master recognizes that the message is not intended for it, but for another slave, so the master immediately forwards the message to the intended slave. This slave-to-slave transfer is a function of the master device and is also used by programming software to upload and download programs to processors on the DF1 Half-Duplex link.

The MicroLogix controllers can only act as slave devices. A device that can act as a master is required. Several Allen-Bradley products support

DF1 Half-Duplex master protocol. They include the SLC 5/03™ and higher processors, enhanced PLC-5

®

processors, and Rockwell Software RSLinx

(version 2.0 and higher) also support DF1 Half-Duplex master protocol.

DF1 Half-Duplex supports up to 255 devices (address 0 to 254) with address 255 reserved for master broadcasts. The MicroLogix controllers support broadcast reception but cannot initiate a broadcast command.

The MicroLogix controllers support Half-Duplex modems using RTS/CTS hardware handshaking.



When the system driver is DF1 Half-Duplex Slave, the following parameters can be changed:

Table E.3 DF1 Half-Duplex Slave Configuration Parameters

Parameter

Baud Rate

Parity

Source ID

(Node Address)

Control Line no handshaking, Half-Duplex modem

Error Detection CRC, BCC

EOT Suppression enabled, disabled

When EOT Suppression is enabled, the slave does not respond when polled if no message is queued. This saves modem transmission power when there is no message to transmit.

Duplicate Packet

(Message) Detect enabled, disabled

Detects and eliminates duplicate responses to a message. Duplicate packets may be sent under noisy communication conditions if the sender’s Message Retries are not set to 0.

Poll Timeout

(x20 ms)

RTS Off Delay

(x20 ms)

RTS Send Delay

(x20 ms)

Message Retries

Pre Transmit Delay

(x1 ms)

Options

300, 600, 1200, 2400, 4800, 9600, 19.2K, 38.4K none, even

0 to 254 decimal

Programming

Software Default

1200 none

1 no handshaking

CRC disabled enabled

0 to 65535 (can be set in 20 ms increments)

Poll Timeout only applies when a slave device initiates a MSG instruction. It is the amount of time that the slave device waits for a poll from the master device. If the slave device does not receive a poll within the Poll Timeout, a MSG instruction error is generated, and the ladder program needs to re-queue the MSG instruction. If you are using a MSG instruction, it is recommended that a Poll Timeout value of zero is not used. Poll Timeout is disabled when set to zero.

3000

0 0 to 65535 (can be set in 20 ms increments)

Specifies the delay time between when the last serial character is sent to the modem and when RTS is deactivated. Gives the modem extra time to transmit the last character of a packet.


Specifies the time delay between setting RTS until checking for the CTS response. For use with modems that are not ready to respond with CTS immediately upon receipt of RTS.

0

0 to 255

Specifies the number of times a slave device attempts to resend a message packet when it does not receive an ACK from the master device. For use in noisy environments where message packets may become corrupted in transmission.


When the Control Line is set to no handshaking, this is the delay time before transmission.

Required for 1761-NET-AIC physical Half-Duplex networks. The 1761-NET-AIC needs delay time to change from transmit to receive mode.

When the Control Line is set to Half-Duplex Modem, this is the minimum time delay between receiving the last character of a packet and the RTS assertion.

3

0



Considerations When Communicating as a DF1 Slave on a Multi-drop

Link

When communication is between either your programming software and a controller or between two controllers via a slave-to-slave connection on a larger multi-drop link, the devices depend on a DF1 Master to give each of them polling permission to transmit in a timely manner. As the number of slaves increases on the link (up to 254), the time between when your programming software or controller is polled also increases. This increase in time may become larger if you are using low baud rates.

As these time periods grow, the following values may need to be changed to avoid loss of communication:

• programming software: increase poll timeout and reply timeout values

•

MicroLogix controller: increase poll timeout

Ownership Timeout

When a program download sequence is started by a software package to download a ladder logic program to the controller, the software takes

“program ownership” of the controller. Program ownership prevents other devices from reading from or writing to the controller while the download is in process. Once the download is completed, the programming software returns the program ownership to the controller, so other devices can communicate with it again.

The controller clears the program ownership if no supported commands are received from the owner within the timeout period. If the program ownership were not cleared after a download sequence interruption, the controller would not accept commands from any other device because it would assume another device still had program ownership.

IMPORTANT

If a download sequence is interrupted, due to electromagnetic interference or other events, discontinue communications to the controller for the ownership

timeout period and then restart the program download.

The ownership timeout period is 60 seconds. After the timeout, you can re-establish communications with the controller and try the program download again. The only other way to remove program ownership is to cycle power to the controller.



Modbus™ RTU Slave

Protocol (MicroLogix

1200 Controllers and

MicroLogix 1500 Series

B and higher Processors only)

This section shows the configuration parameters for Modbus RTU Slave

(Remote Terminal Unit transmission mode) protocol. For more information about the Modbus Slave protocol, see the Modbus Protocol

Specification (available from http://www.modicon.com/techpubs/).

The Modbus RTU slave driver maps the four Modbus data types—Coils,

Contacts, Input Registers, and Holding Registers—into four binary and/or integer data table files created by the user. The coil and contact files can contain up to 4096 coils or contacts in each register when the data table file is configured for a maximum size of 256 words. The input register and holding register files can contain up to 256 registers when the data table file is configured for a maximum size of 256 words.

The modbus Memory map is summarized in Table E.4 and detailed in

Table E.5 below:

Table E.4 Modbus to MicroLogix Memory Map - Summary

(MicroLogix 1200 Controllers and MicroLogix 1500 1764-LSP Series B and 1764-LRP Processors only)

Modbus

Addressing

Description

0001 to 4096 Read/Write Modbus Coil Data space

10001 to 14096 Read-Only Modbus Contact Data space

30001 to 30256

30501 to 30532

Read-Only Modbus Input Register space

Modbus Communication Parameters

41501 to 41566 Read/Write System Status File space

Valid MicroLogix Addressing

File Type Data File Number Address

Bit (B) or Integer (N)



Communication Status File

31501 to 31566 Read-Only System Status File space Status (S)

40001 to 40256 Read/Write Modbus Holding Register space Bit (B) or Integer (N)

Status (S)

-

3 to 255

3 to 255

3 to 255

2

3 to 255

2

bits 0 to 4095 bits 0 to 4095 words 0 to 255 words 0 to 65 words 0 to 255 words 0 to 65



Table E.5 Modbus to MicroLogix Memory Map - Detail


30521

30522

30523

30524

30525

30526

30527

30528

30513

30514

30515

30516

30517

30518

30519

30520

30506

30507

30508

30509

30510

30511

30512

30512

Modbus Addressing Modbus Address Reference

0001 to 4096 Read/Write Modbus Coil Data space

10001 to 14096

30001 to 30256

Read Only Modbus Contact Data space

Read Modbus Input Register space

30501

30502

30503

30504

Modbus Data Table Coil File Number

Modbus Data Table Contact File Number

Modbus Data Table Input Register File Number

Modbus Data Table Holding Register File Number

Pre-Send Delay

Modbus Slave Address

Inter-character Timeout

RTS Send Delay

RTS Off Delay

Parity



30529

30530

30531

30532

31501 to 31566

40001 to 40256

41501 to 41566

Presentation Layer Error Count

Executed Function Code Error

Last Transmitted Exception Code

File Number of Error Request

Element Number of Error Request

Function Code 1 Message Counter - Read Single Output Coil

Function Code 2 Message Counter - Read Discrete Input Image

Function Code 3 Message Counter - Read Single Holding Register

Function Code 4 Message Counter - Read Single Input Register

Function Code 5 Message Counter - Set/Clear Single Output Coil

Function Code 6 Message Counter - Read/Write Single Holding Register

Function Code 8 Message Counter - Run Diagnostics

Function Code 15 Message Counter - Set/Clear for Block of Output Coils

Modem Status

Total messages responded to by this slave

Total messages to this Slave

Total Messages Seen

Link Layer Error Count

Link Layer Error

Read Only System Status File

Read/Write Modbus Holding Register space.

Read/Write System Status File

4

4

4

4

4

4

4

4

4

4

4

4

4

Function Code 16 Message Counter - Read/Write for Block of Holding Registers 4

4

4

4

4

4

4

4

3, 6, 16

3, 6, 16

4

4

4

4

4

4

4

4

4

4

4

4

2

4

Modbus Function Code (decimal)

1, 5, 15



The controller responds to the Modbus command function codes listed in

Table E.6 below:

Table E.6 Supported Modbus Commands


Command

Read Coil Status

Read Input Status

Read Holding Registers

Read Input Registers

Set and Reset Single Coil

Write Single Holding Register

Echo Command Data

Clear Diagnostic Counters

Set and Reset Multiple Coils

Write Multiple Holding Registers

6

8

8

15

16

4

5

2

3

Function Code

(decimal)

1

-

-

0

-

10

-

-

-

-

-

Subfunction Code

(decimal)

Upon receiving a Modbus command that is not supported or improperly formatted, the controller will respond with one of the exception codes

listed in Table E.7 below:

Table E.7 Modbus Error Codes


Error

Code

0

1

2

5

6

3

4

Error Description

No error.

Function Code cannot Broadcast.

The function does not support Broadcast.

Function Code not supported.

The controller does not support this Modbus function or subfunction.

Bad Command Length.

Bad Length.

Bad parameter

Bad File Type

The Modbus Command is the wrong size.

The function attempted to read/write past the end of a data file.

The function cannot be executed with these parameters.

The file number being referenced is not the proper file type.

7

8

9

10

Bad File Number

Bad Modbus Address

Table Write protected

File Access Denied

The file number does not exist

The function attempted to access an invalid Modbus address.

(2)

The function attempted to write to a read-only file.

Access to this file is not granted.

11 File Already Owned Data file is already owned by another process,

(1) If Modbus Command is sent with a valid Broadcast address, then no exception reply will be sent for Error Codes 2 through 11.

(2) See Table E.4 on pageE-9 for valid Modbus memory mapping.

3

3

1

2

Transmitted

Exception Code

(1)

none nothing transmitted

1

2

3

3

2

2



When the system driver is Modbus RTU Slave, the following communication port parameters can be changed:

Table E.8 Modbus RTU Slave Communications Configuration Parameters

(MicroLogix 1200 Controllers and MicroLogix 1500 Series B and higher Processors only)

Parameter Options

Baud Rate

Parity

Node Address

Control Line

Inter-character

Timeout (x1 ms)

Modbus Data Table

File Number

Assignment

RTS Off Delay

(x20 ms)

RTS Send Delay

(x20 ms)

Pre Transmit Delay

(x1 ms)

300, 600, 1200, 2400, 4800, 9600, 19.2K, 38.4K none, even, odd

1 to 247 decimal no handshaking, Half-Duplex modem

0 to 6553 (can be set in 1 ms increments); 0 = 3.5 character times

Specifies the minimum delay between characters that indicates the end of a message packet.

0

Coils (Discrete outputs, Modbus addresses 0001 to 4096) range = 3 to 255, 0 = no file 0

Contacts (Discrete inputs, Modbus addresses 10001 to 14096) range = 3 to 255, 0 = no file 0

Input Registers (Read Only, Modbus addresses 30001 to 30256) range = 3 to 255, 0 = no file 0

Holding Registers (Read/Write, Modbus addresses 40001 to 40256) range = 3 to 255, 0 = no file

0


Specifies the delay time between when the last serial character is sent to the modem and when RTS is deactivated. Gives the modem extra time to transmit the last character of a packet.

0


Specifies the time delay between setting RTS until checking for the CTS response. For use with modems that are not ready to respond with CTS immediately upon receipt of RTS.


When the Control Line is set to no handshaking, this is the delay time before transmission.

Required for 1761-NET-AIC physical Half-Duplex networks. The 1761-NET-AIC needs delay time to change from transmit to receive mode.

When the Control Line is set to Half-Duplex Modem, this is the minimum time delay between receiving the last character of a packet and the RTS assertion.

0

0

Programming


19.2K

none

1 no handshaking



ASCII Driver

(MicroLogix 1200 and

1500 Series B and higher

Controllers only)

The ASCII driver provides connection to other ASCII devices, such as bar code readers, weigh scales, serial printers, and other intelligent devices.

You can use ASCII by configuring the RS-232 port, channel 0 for ASCII driver (For the 1764-LRP only, you can select either Channel 0 or Channel

1). When configured for ASCII, all received data is placed in a buffer. To access the data, use the ASCII instructions in your ladder program. See

ASCII Instructions on page 20-1 for information on using the ASCII

instructions. You can also send ASCII string data to most attached devices that accept ASCII data/characters.

NOTE

Only ASCII instructions can be used when a channel is configured for ASCII. If you use a Message (MSG) instruction that references the channel, an error occurs.

The channel configuration screen is shown below:

The controller updates changes to the channel configuration at the next execution of a Service Communications (SVC) instruction, I/O Refresh

(REF) instruction, or when it performs Communications Servicing, whichever comes first.



When the driver is set to ASCII, the following parameters can be changed:

Table E.9 ASCII Channel Configuration Parameters

Parameter Description

Baud Rate

Parity

Toggles between the communication rate of 300, 600, 1200, 2400, 4800, 9600, 19.2K, and 38.4K.

Toggles between None, Odd, and Even.

Termination 1 Specifies the first termination character. The termination character defines the one or two character sequence used to specify the end of an ASCII line received. Setting the first ASCII termination character to undefined (\ff) indicates no ASCII receiver line termination is used.

\d

Programming


1200

None

Termination 2 Specifies the second termination character. The termination character defines the one or two character sequence used to specify the end of an ASCII line received. Setting the second ASCII

Termination character to undefined (\ff) and the first ASCII Termination character to a defined value

(\d) indicates a single character termination sequence.

\ff

Control Line Toggles between No Handshaking, Half-Duplex Modem, and Full-Duplex Modem No Handshaking

Delete Mode The Delete Mode allows you to select the mode of the “delete” character. Toggles between Ignore,

CRT, and Printer.

Delete Mode affects the characters echoed back to the remote device. When Delete Mode is enabled, the previous character is removed from the receive buffer.

•

In CRT mode, when a delete character is encountered, the controller echos three characters to the device: backspace, space, and backspace. This erases the previous character on the terminal.

•

In Printer Mode, when a delete character is encountered, the controller echos the slash character, then the deleted character.

Enable the Echo parameter to use Delete Mode.

Ignore

Echo

XON/XOFF Allows you to Enable or Disable XON/ XOFF software handshaking. XON/XOFF software handshaking involves the XON and XOFF control characters in the ASCII character set.

When the receiver receives the XOFF character, the transmitter stops transmitting until the receiver receives the XON character. If the receiver does not receive an XON character after 60 seconds, the transmitter automatically resumes sending characters.

Also, when the receive buffer is more than 80% full, an XOFF character is sent to the remote device to pause the transmission. Then, when the receive buffer drops to less than 80% full, an XON character is sent to the remote device to resume the transmission.

Disabled

RTS Off Delay

(x20 ms)

When Echo Mode is enabled, all of the characters received are echoed back to the remote device. This Disabled allows you to view characters on a terminal connected to the controller. Toggles between Enabled and

Disabled.

Allows you to select the delay between when a transmission is ended and when RTS is dropped.

Specify the RTS Off Delay value in increments of 20 ms. Valid range is 0 to 65535.

0

RTS Send

Delay (x20 ms)

Allows you to select the delay between when RTS is raised and the transmission is initiated. Specify the RTS Send Delay value in increments of 20 ms. Valid range is 0 to 65535.

0


1

Glossary

The following terms are used throughout this manual. Refer to the

Allen-Bradley Industrial Automation Glossary, Publication Number

AG-7.1, for a complete guide to Allen-Bradley technical terms.

address

A character string that uniquely identifies a memory location. For example, I:1/0 is the memory address for data located in Input file word

1, bit 0.

AIC+ Advanced Interface Converter

A device that provides RS-232 isolation to an RS-485 Half-Duplex communication link. (Catalog Number 1761-NET-AIC.)

application

1) A machine or process monitored and controlled by a controller. 2) The use of computer- or processor-based routines for specific purposes.

ASCII

American Standard Code for Information Interchange. A standard for defining codes for information exchange between equipment produced by different manufacturers. The basis of character sets used in most microcomputers; a string of 7 binary digits represents each character.

baud rate

The speed of communication between devices. Baud rate is typically displayed in K baud. For example, 19.2K baud = 19,200 bits per second.

bit

The smallest unit of memory used in discrete or binary logic, where the value 1 represents ON and 0 represents OFF.

block diagrams

A method used to illustrate logic components or a sequence of events.

Boolean operators

Logical operators such as AND, OR, NAND, NOR, NOT, and Exclusive-OR that can be used singularly or in combination to form logic statements or circuits. Can have an output response of T or F.

branch

A parallel logic path within a rung of a ladder program. Its primary use is to build OR logic.

communication scan

A part of the controller’s operating cycle. Communication with devices

(such as other controllers and operator interface devices) takes place during this period.

control program

User logic (the application) that defines the controller’s operation.


Glossary 2


controller

A device, such as a programmable controller, used to control output devices.

controller overhead

A portion of the operating cycle used for housekeeping purposes

(memory checks, tests, communications, etc.).

control profile

The means by which a controller determines which outputs turn on under what conditions.

counter

A device that counts the occurrence of some event.

CPU (Central Processing Unit)

The decision-making and data storage section of a programmable controller.

data table

The part of processor memory that contains I/O status and files where user data (such as bit, integer, timers, and counters) is monitored, manipulated, and changed for control purposes.

DIN rail

Manufactured according to Deutsche Industrie Normenausshus (DIN) standards, a metal railing designed to ease installation and mounting of your devices.

download

The transfer of program or data files to a device.

DTE

Data Terminal Equipment

EMI

Electromagnetic interference.

embedded I/O

Embedded I/O is the controller’s on-board I/O. For MicroLogix controllers, embedded I/O is all I/O residing at slot 0.

expansion I/O

Expansion I/O is I/O that is connected to the controller via a bus or cable.

MicroLogix 1200 controllers use Bulletin 1762 expansion I/O. MicroLogix

1500 controllers use Bulletin 1769 expansion I/O. For MicroLogix controllers, embedded I/O is all I/O residing at slot 1 and higher.

Glossary 3

encoder

A device that detects position, and transmits a signal representing that position.

executing mode

Any run or test mode.

false

The status of an instruction that does not provide a continuous logical path on a ladder rung.

FET

Field Effect Transistor. DC output capable of high-speed operation.

FIFO (First-In-First-Out)

The order that data is stored and retrieved from a file.

file

A collection of data or logic organized into groups.

full-duplex

A mode of communication where data may be transmitted and received simultaneously (contrast with half-duplex).

half-duplex

A mode of communication where data transmission is limited to one direction at a time.

hard disk

A storage device in a personal computer.

high byte

Bits 8 to 15 of a word.

housekeeping

The portion of the scan when the controller performs internal checks and services communications.

input device

A device, such as a push button or a switch, that supplies an electrical signal to the controller.

input scan

The controller reads all input devices connected to the input terminals.

inrush current

The temporary surge of current produced when a device or circuit is initially energized.


Glossary 4


instruction

A mnemonic defining an operation to be performed by the processor. A rung in a program consists of a set of input and output instructions. The input instructions are evaluated by the controller as being true or false. In turn, the controller sets the output instructions to true or false.

instruction set

The set of instructions available within a controller.

I/O

Input and Output

jump

Changes the normal sequence of program execution. In ladder programs a JUMP (JMP) instruction causes execution to jump to a specific rung in the user program.

ladder logic

A graphical programming format resembling a ladder-like diagram. The ladder logic programing language is the most common programmable controller language.

least significant bit (LSB)

The element (or bit) in a binary word that carries the smallest value of weight.

LED (Light Emitting Diode)

Used as status indicator for processor functions and inputs and outputs.

LIFO (Last-In-First-Out)

The order that data is stored and retrieved from a file.

low byte

Bits 0 to 7 of a word.

logic

A general term for digital circuits or programmed instructions to perform required decision making and computational functions.

Master Control Relay (MCR)

A hard-wired relay that can be de-energized by any series-connected emergency stop switch.

mnemonic

A simple and easy to remember term that is used to represent a complex or lengthy set of information.

Modbus™ RTU Slave

A half-duplex serial communication protocol.

Glossary 5

modem

Modulator/demodulator. Equipment that connects data terminal equipment to a communication line.

modes

Selected methods of operation. Example: run, test, or program.

negative logic

The use of binary logic in such a way that “0” represents the desired voltage level.

network

A series of stations (nodes) connected by some type of communication medium. A network may be made up of a single link or multiple links.

nominal input current

The typical amount of current seen at nominal input voltage.

normally closed

Contacts on a relay or switch that are closed when the relay is de-energized or deactivated. They are open when the relay is energized or the switch is activated.

normally open

Contacts on a relay or switch that are open when the relay is de-energized or the switch is deactivated. They are closed when the relay is energized or the switch is activated.

off-delay time

The OFF delay time is a measure of the time required for the controller logic to recognize that a signal has been removed from the input terminal of the controller. The time is determined by circuit component delays and by any applied filter.

offline

When a device is not scanning/controlling or when a programming device is not communicating with the controller.

offset

A continuous deviation of a controlled variable from a fixed point.

off-state leakage current

When a mechanical switch is opened (off-state), no current flows through the switch. Semiconductor switches and transient suppression components which are sometimes used to protect switches, have a small current flow when they are in the off state. This current is referred to as the off-state leakage current. To ensure reliable operation, the off-state leakage current rating must be less than the minimum operating current rating of the device that is connected.


Glossary 6


on-delay time

The ON delay time is a measure of the time required for the controller logic to recognize that a signal has been presented at the input terminal of the controller.

one shot

A programming technique that sets a bit ON or OFF for one program scan.

online

When a device is scanning/controlling or when a programming device is communicating with the controller.

operating voltage

For inputs, the voltage range needed for the input to be in the On state.

For outputs, the allowable range of user-supplied voltage.

output device

A device, such as a pilot light or a motor starter coil, that receives a signal or command from the controller.

output scan

The controller turns on, off, or modifies the devices connected to the output terminals.

PCCC

Programmable Controller Communications Commands

processor

A Central Processing Unit. (See CPU.)

processor files

The set of program and data files resident in the controller.

program file

Areas within a processor that contain the logic programs. MicroLogix controllers support multiple program files.

program mode

When the controller is not scanning the control program.

program scan

A part of the controller’s operating cycle. During the program scan, the logic program is processed and the Output Image is updated.

programming device

Programming package used to develop ladder logic diagrams.

protocol

The rules of data exchange via communications.

Glossary 7

read

To acquire data. For example, the processor reads information from other devices via a read message.

relay

An electrically operated device that mechanically switches electrical circuits.

relay logic

A representation of binary or discrete logic.

restore

To transfer a program from a device to a controller.

reserved bit

A location reserved for internal use.

retentive data

Information (data) that is preserved through power cycles.

RS-232

An EIA standard that specifies electrical, mechanical, and functional characteristics for serial binary communication circuits.

run mode

An executing mode during which the controller scans or executes the logic program.

rung

A rung contains input and output instructions. During Run mode, the inputs on a rung are evaluated to be true or false. If a path of true logic exists, the outputs are made true (energized). If all paths are false, the outputs are made false (de-energized).

RTU

Remote Terminal Unit

save

To save a program to a computer hard disk.

scan

The scan is made up of four elements: input scan, program scan, output scan, and housekeeping.

scan time

The time required for the controller to complete one scan.

sinking

A term used to describe current flow between two devices. A sinking device provides a direct path to ground.


Glossary 8

sourcing

A term used to describe current flow between two devices. A sourcing device or circuit provides a power.

status

The condition of a circuit or system.

terminal

A point on an I/O module that external devices, such as a push button or pilot light, are wired to.

throughput

The time between when an input turns on and a corresponding output turns on or off. Throughput consists of input delays, program scan, output delays, and overhead.

true

The status of an instruction that provides a continuous logical path on a ladder rung.

upload

Data is transferred from the controller to a programming or storage device.

watchdog timer

A timer that monitors a cyclical process and is cleared at the conclusion of each cycle. If the watchdog runs past its programmed time period, it causes a fault.

write

To send data to another device. For example, the processor writes data to another device with a message write instruction.


A

ABL instruction

20-14

ACB instruction

20-15

accuracy, timer

8-3

ACI instruction

20-16

ACL instruction

20-7

ACN instruction

20-18

active nodes status

C-14

ADD instruction

10-4

address

G-1

addressing

direct addressing

4-3

I/O

1-7

immediate addressing

4-3

indirect addressing

4-4

indirect addressing of a bit

4-6

indirect addressing of a file

4-5

indirect addressing of a word

4-4

modes

4-3

using in-line indirection

20-29

AEX instruction

20-19

AHL instruction

20-20

AIC instruction

20-8

AIC+ Advanced Interface Converter

G-1

Allen-Bradley

contacting for assistance

P-3

,

D-9

support

P-3

allow future access setting

2-10

AND instruction

12-3

application

G-1

ARD instruction

20-22

arithmetic flags

C-3

ARL instruction

20-23

ASC instruction

20-25

ASCII definition

G-1

ASCII character set

20-31

ASCII clear buffers instruction

20-7

ASCII control data file

20-6

ASCII file

20-5

ASCII handshake lines instruction

20-20

ASCII instruction error codes

20-30

ASCII instructions

20-1

error codes

20-30

status bits

20-5

,

20-6

,

22-9

timing diagram

20-28

ASCII integer to string instruction

20-8

ASCII number of characters in buffer instruction

20-15

Index

ASCII protocol parameters

20-4

ASCII read characters instruction

20-22

ASCII read line instruction

20-23

ASCII string compare instruction

20-26

ASCII string concatenate

20-18

ASCII string extract

20-19

ascii string manipulation error

C-13

ASCII string search instruction

20-25

ASCII string to integer instruction

20-16

ASCII test buffer for line instruction

20-14

ASCII timing diagram

20-28

ASCII write instruction

20-11

ASCII write with append instruction

20-9

ASR instruction

20-26

AWA and AWT timing diagram

20-28

AWA instruction

20-9

AWT instruction

20-11

B

base hardware information file

3-12

battery life expectancy

3-4

operation

3-4

battery low status bit

C-13

baud rate

G-1

baud rate status

C-15

BHI Function File

3-12

bit

G-1

bit instructions

7-1

bit shift left instruction

14-4

bit shift right instruction

14-6

bit-wise AND instruction

12-3

block diagrams

G-1

Boolean operators

G-1

branch

G-1

BSL instruction

14-4

BSR instruction

14-6

C

carry flag

C-3

catalog number status

C-20

channel 0 communications status

C-16

CS0 communications status file

3-13

channel configuration

DF1 full-duplex parameters

E-5

DF1 half-duplex parameters

E-7

DH485 parameters

E-3


2 Index

Modbus RTU Slave parameters

E-12

clear instruction

10-6

clearing

controller faults

D-1

controller memory

2-10

clock, free running

C-10

CLR instruction

10-6

common techniques used in this manual

P-2

communication instructions

21-1

communication protocols

DF1 full-duplex

E-5

DF1 half-duplex

E-6

DH485

E-2

Modbus Slave RTU

E-9

communication scan

G-1

communications

active status bit

C-17

channel 0 status

C-16

mode selection status bit

C-17

status file

3-13

compare instructions

9-1

compiler revision

build number status

C-21

release status

C-21

contacting Allen-Bradley for assistance

P-3

contacting Rockwell Automation for assistance

D-9

control profile

G-2

control program

G-1

control register error status bit

C-11

controller

definition

G-2

fault messages

D-2

mode

C-7

mode status

C-4

overhead

A-7

,

B-6

,

G-2

status file

C-1

conversion instructions

11-1

convert from binary coded decimal (BCD) instruction

11-4

convert to binary coded decimal (BCD) instruction

11-8

COP instruction

14-2

copy file instruction

14-2

count down instruction

8-9

count up instruction

8-9

counters counter file

8-7

counter file and status bits

8-8

definition

G-2

how counters work

8-7

CPU (central processing unit), definition

G-2


CS function file

3-13

CTD instruction

8-9

CTU instruction

8-9

D

DAT configuration

3-9

function file

3-9

data file overwrite protection lost status bit

C-18

data files

2-2

,

2-5

bit (B)

2-5

control (R)

2-5

counter (C)

8-7

I/O images for expansion modules (MicroLogix 1200)

1-4

I/O images for expansion modules (MicroLogix 1500)

1-9

input (I)

2-5

input and output addressing examples

1-13

integer (N)

2-5

long word (L)

2-5

message (MG) file

21-4

organization and addressing

20-5

output (O)

2-5

PID (PD)

19-2

protecting data files

2-6

status (S) file

C-1

string (ST) file

20-5

timer (T)

8-1

data logging

22-1

data table

G-2

DCD instruction

11-2

decode 4 to 1-of-16 instruction

11-2

DF1 full-duplex protocol

E-5

configuration parameters

E-5

description

E-5

DF1 half-duplex protocol

E-6


E-7

description

E-6

DH485 communication protocol

E-2


E-3

DH485 network configuration parameters

E-3

description

E-2

protocol

E-2

token rotation

E-2

DIN rail

G-2

DIV instruction

10-5

divide instruction

10-5

DLG Instruction

22-8

download

G-2

DTE, definition

G-2

E

EII function file

18-17

embedded I/O

1-1

EMI

G-2

ENC instruction

11-3

encode 1-of-16 to 4 instruction

11-3

encoder definition

G-3

quadrature

5-20

END instruction

16-5

EQU instruction

9-3

equal instruction

9-3

error codes

D-1

,

D-2

ASCII instruction error codes

20-30

EII error codes

18-18

fault messages and error codes

D-1

HSC error codes

5-5

major error code status

C-13

math overflow trap bit

10-3

math status bits

10-3

MSG instruction error codes

21-21

PID runtime errors

19-16

PTO error codes

6-17

PWM error codes

6-25

STI error code

18-13

troubleshooting guide

D-2

errors, identifying

D-1

event input interrupt (EII) function file

18-17

examine if closed instruction

7-1

examine if open instruction

7-1

exclusive OR instruction

12-5

executing mode

G-3

execution time

MicroLogix 1200 instructions

A-1


B-1

expansion I/O

1-3

,

1-7

analog I/O configuration

1-5

,

1-11

discrete I/O configuration

1-4

,

1-9

F

false

G-3

fault messages

D-1

,

D-2

fault override at power-up bit

C-5

fault recovery procedure

D-2

fault routine description of operation

18-6

Index 3 file number status

C-16

manually clearing faults

D-2

operation in relation to main control program

18-2

priority of interrupts

18-4

faults automatically clearing

D-1

identifying

D-1

manually clearing using the fault routine

D-2

recoverable and non-recoverable

18-6

FET

G-3

FFL instruction

14-8

FFU instruction

14-11

FIFO (First-In-First-Out)

G-3

FIFO load instruction

14-8

FIFO unload instruction

14-11

file

G-3

file instructions

14-1

fill file instruction

14-3

filtering, inputs

1-14

first scan status bit

C-8

FLL instruction

14-3

forces enabled status bit

C-4

forces installed status bit

C-4

forcing, inputs and outputs

1-14

FRD

example

11-6

instruction

11-4

free running clock

C-10

free running clock status

C-10

full-duplex

G-3

function files

3-1

,

3-2

base hardware information (BHI)

3-12

communications status (CS) file

3-13

DAT function file

3-9

event input interrupt (EII)

18-17

high-speed counter (HSC)

5-2

input/output status file (IOS)

3-18

memory module information (MMI)

3-6

pulse train output (PTO)

6-6

pulse width modulation (PWM)

6-19

real-time clock (RTC)

3-3

selectable timed interrupt (STI)

18-12

trim pot information (TPI)

3-5

future access status bit

C-8

G

GEQ instruction

9-5

greater than instruction

9-4

greater than or equal to instruction

9-5


4 Index

GRT instruction

9-4

H

half-duplex

G-3

hard disk

G-3

high byte

G-3

high-speed counter function file

5-2

high-speed counter load instruction

5-26

high-speed outputs

6-1

housekeeping

G-3

HSC function file

5-2

HSL instruction

5-26

I

I/O

G-4

I/O addressing

1-7

I/O configuration

1-1

I/O forcing

1-14

I/O refresh instruction

17-4

identifying controller faults

D-1

IIM instruction

17-1

immediate input with mask instruction

17-1

immediate output with mask instruction

17-3

in-line indirection

20-29

input and output instructions

17-1

input device

G-3

input filter selection modified status bit

C-13

input filtering

1-14

input scan

G-3

input/output status file

3-18

inrush current

G-3

instruction

G-4

instruction execution time

B-1

instruction set

definition

G-4

MicroLogix 1200 execution times

A-1

MicroLogix 1500 execution times

B-1

overview

4-1

INT instruction

18-7

interrupt subroutine instruction

18-7

interrupts interrupt instructions

18-7

interrupt subroutine (INT) instruction

18-7

latency

18-5

overview

18-1

selectable timed start (STS) instruction

18-8

user fault routine

18-6

user interrupt disable (UID) instruction

18-9


user interrupt enable (UIE) instruction

18-10

user interrupt flush (UIF) instruction

18-11

IOM instruction

17-3

IOS function file

3-18

J

JMP instruction

16-1

JSR instruction

16-2

jump

G-4

jump to label instruction

16-1

jump to subroutine instruction

16-2

L

label instruction

16-2

ladder logic

G-4

last 100 µSec scan time status

C-17

latching inputs

1-15

LBL instruction

16-2

least significant bit (LSB)

G-4

LED (light emitting diode)

G-4

LEQ instruction

9-5

LES instruction

9-4

less than instruction

9-4

less than or equal to instruction

9-5

LFL instruction

14-14

LFU instruction

14-17

LIFO (Last-In-First-Out)

G-4

LIFO load instruction

14-14

LIFO unload instruction

14-17

LIM instruction

9-7

limit instruction

9-7

load memory module always bit

C-6

load memory module on error or default program bit

C-5

local messages

21-7

logic

G-4

logical instructions

12-1

logical NOT instruction

12-6

logical OR instruction

12-4

low byte

G-4

M

major error code status

C-13

major error detected in user fault routine status bit

C-11

major error halted status bit

C-8

manuals, related

P-2

mask compare for equal instruction

9-6

masked move instruction

13-3

master control relay (MCR)

G-4

Index 5 master control reset instruction

16-5

math instructions

10-1

math overflow selection bit

C-10

math register status

C-15

maximum scan time status

C-15

MCR instruction

16-5

memory

2-2

clearing controller memory

2-10

memory module boot status bit

C-12

memory module compare bit

C-9

memory module information function file

3-6

fault override

3-7

functionality type

3-6

load always

3-8

load on error

3-8

mode behavior

3-8

module present

3-7

program compare

3-7

write protect

3-7

memory module password mismatch status bit

C-12

memory usage


A-1


B-1

MEQ

9-6

MEQ instruction

9-6

message (MG) file

21-4

message errors

21-21

message instruction

21-3

message reply pending status bit

C-16

messages local

21-7

local messaging examples

21-29

remote

21-16

messaging overview

21-1

minor error bits

C-11

MMI function file

3-6

mnemonic

G-4

Modbus definition

G-4

Modbus slave RTU protocol

E-9

Modbus to MicroLogix memory map

E-9

,

E-10

,

E-11

mode behavior

C-7

mode status

C-4

modem

G-5

modes

G-5

monitoring controller operation, fault recovery procedure

D-2

MOV instruction

13-1

move instructions

13-1

MSG instruction

21-3

error codes

21-21

ladder logic

21-28

local messaing examples

21-29

timing diagram

21-23

MUL instruction

10-5

multiply instruction

10-5

MVM instruction

13-3

N

NEG instruction

10-6

negate instruction

10-6

negative logic

G-5

NEQ instruction

9-3

network

G-5

node address status

C-15

nominal input current

G-5

normally closed

G-5

normally open

G-5

not equal instruction

9-3

NOT instruction

12-6

O

OEM lock

2-10

OEM lock status bit

C-8

offline

G-5

offset

G-5

off-state leakage current

G-5

one shot

G-6

one shot falling instruction

7-6

one shot instruction

7-5

one shot rising instruction

7-6

online

G-6

ONS instruction

7-5

operating system

catalog number status

C-20

FRN status

C-20

series letter status

C-20

operating voltage

G-6

OR instruction

12-4

OSF instruction

7-6

OSR instruction

7-6

OTE instruction

7-3

OTL instruction

7-4

OTU instruction

7-4

outgoing message command pending status bit

C-17

output device

G-6

output instruction

7-3

output latch instruction

7-4

output scan

G-6


6 Index output unlatch instruction

7-4

overflow flag

C-3

overflow trap status bit

C-11

ownership timeout

E-8

P

password protection

2-9

PCCC

G-6

PD data file

19-2

PID

analog I/O scaling

19-17

application examples

19-22

application notes

19-18

errors

19-16

PID concept

19-1

PID equation

19-2

PID instruction

19-3

tuning parameters

19-8

power save timeout

3-9

power-up mode behavior bit

C-6

process control instruction

19-1

processor

G-6

processor battery low status bit

C-13

processor catalog number status

C-20

processor files

G-6

processor revision status

C-20

processor series status

C-20

program control instructions

16-1

program end instruction

16-5

program file

definition

G-6

memory structure

2-2

program mode

G-6

program scan

definition

G-6

MicroLogix 1200 scan time worksheet

A-7

MicroLogix 1500 scan time worksheet

B-6

programming device

G-6

proportional integral derivative

application notes

19-18

PID instruction

19-3

PID tuning

19-22

runtime errors

19-16

the PID concept

19-1

the PID equation

19-2

protocol

G-6

DF1 full-duplex

E-5

DF1 half-duplex

E-6

DH485 communication

E-2


Modbus slave RTU

E-9

protocol configuration

E-1

PTO function file

6-6

instruction

6-1

publications, related

P-2

pulse train output function file

6-6

instruction

6-1

pulse width modulation function file

6-19

instruction

6-18

Purpose of this Manual

P-1

PWM function file

6-19

instruction

6-18

Q

quadrature encoder

5-20

R

RAC instruction

5-27

read

G-7

real time clock accuracy

3-3

battery low indicator bit

3-4

disabling

3-4

function file

3-3

REF instruction

17-4

refresh instruction

17-4

related publications

P-2

relay

G-7

relay logic

G-7

relay-type instructions

7-1

remote messages

21-16

remote packet support

E-4

RES instruction

8-10

reserved bit

G-7

reset accumulated value instruction

5-27

reset instruction

8-10

restore

G-7

RET instruction

16-3

retentive data

G-7

retentive data lost status bit

C-12

retentive timer on-delay instruction

8-6

return from subroutine instruction

16-3

RS-232, definition

G-7

RTC

day of month status

C-18

day of week status

C-19

function file

3-3

hours status

C-19

minutes status

C-19

month status

C-18

seconds status

C-19

year status

C-18

RTO instruction

8-6

RTU, definition

G-7

run mode

G-7

rung

G-7

S

save

G-7

SBR instruction

16-3

scale instruction

10-7

scale with parameters instruction

10-8

scan

G-7

scan time

G-7

last 100 µSec scan time status

C-17

maximum scan time status

C-15

scan time worksheet

MicroLogix 1200

A-7

MicroLogix 1500

B-6

scan toggle status bit

C-17

SCL instruction

10-7

SCP instruction

10-8

selectable timed interrupt (STI) function file

18-12

selectable timed start instruction

18-8

sequencer compare instruction

15-2

sequencer instructions

15-1

sequencer load instruction

15-8

sequencer output instruction

15-5

service communications instruction

21-26

sign flag

C-3

sinking

G-7

sourcing

G-8

SQC instruction

15-2

SQL instruction

15-8

SQO instruction

15-5

SQR instruction

10-9

square root instruction

10-9

startup protection fault bit

C-5

static file protection

2-8

status

G-8

status file

C-1

STI enabled bit

C-9

Index 7 executing bit

C-9

file number status

C-16

function file

18-12

lost status bit

C-12

mode status

C-9

pending status bit

C-9

set point status

C-16

string data file

20-5

STS instruction

18-8

SUB instruction

10-4

subroutine label instruction

16-3

subtract instruction

10-4

SUS instruction

16-4

suspend code status

C-14

suspend file status

C-14

suspend instruction

16-4

SVC instruction

21-26

swap instruction

10-10

SWP instruction

10-10

T

target bit file

3-9

,

3-11

target integer file

3-9

temporary end instruction

16-4

terminal

G-8

throughput

G-8

timer accuracy

8-3

timer and counter instructions

8-1

timer files

8-1

timer off-delay instruction

8-5

timer on-delay instruction

8-4

timing diagrams

ASCII

20-28

AWA and AWT instructions

20-28

latching inputs

1-15

MSG instruction

21-23

PTO relative timing

6-4

quadrature encoder

5-20

TND instruction

16-4

TOD instruction

11-8

changes to the math register

11-9

example

11-9

TOF instruction

8-5

TON instruction

8-4

TPI function file

3-5

trim pots

3-5

error conditions

3-5

function file

3-5

troubleshooting

D-2

,

D-9


8 Index

automatically clearing faults

D-1

contacting Allen-Bradley for assistance

P-3

,

D-9

identifying controller faults

D-1

manually clearing faults

D-2

using the fault routine

D-2

true

G-8

U

UID instruction

18-9

UIE instruction

18-10

UIF instruction

18-11

upload

G-8

user application mode status

C-4

user fault routine

creating a user fault routine

18-6

file number status

C-16

major error detected status bit

C-11

recoverable and non-recoverable faults

18-6

user interrupt disable instruction

18-9

user interrupt enable instruction

18-10

user interrupt flush instruction

18-11

user program functionality type status

C-21

W

watchdog scan time

C-10

write

G-8

X

XIC instruction

7-1

XIO instruction

7-1

XOR instruction

12-5

Z

zero flag

C-3


9

MicroLogix 1200 and 1500

Alphabetical List of Instructions

Instruction- Description

ABL - Test Buffer for Line

ACB - Number of Characters in Buffer

ACI - String to Integer

ACL - ASCII Clear Buffers

ACN - String Concatenate

ADD - Add

AEX - String Extract

AHL - ASCII Handshake Lines

AIC - ASCII Integer to String

AND - Bit-Wise AND

ARD - ASCII Read Characters

ARL - ASCII Read Line

ASC - String Search

ASR - ASCII String Compare

AWA - ASCII Write with Append

AWT - ASCII Write

BSL - Bit Shift Left

BSR - Bit Shift Right

CLR - Clear

COP - Copy File

CTD - Count Down

CTU - Count Up

DCD - Decode 4 to 1-of-16

DIV - Divide

DLG - Data Log Instruction

ENC - Encode 1-of-16 to 4

END - Program End

EQU - Equal

FFL - First In, First Out (FIFO) Load

FFU - First In, First Out (FIFO) Unload

FLL - Fill File

FRD - Convert from Binary Coded Decimal (BCD)

GEQ - Greater Than or Equal To

GRT - Greater Than

HSL - High-Speed Counter Load

IIM - Immediate Input with Mask

INT - Interrupt Subroutine

IOM - Immediate Output with Mask

JMP - Jump to Label

JSR - Jump to Subroutine

LBL - Label

LEQ - Less Than or Equal To

LES - Less Than

LFL - Last In, First Out (LIFO) Load

LFU - Last In, First Out (LIFO) Unload

LIM - Limit Test

10-5

22-8

11-3

16-5

9-3

14-8

14-11

14-3

20-11

14-4

14-6

10-6

14-2

8-9

8-9

11-2

20-20

20-8

12-3

20-22

20-23

20-25

20-26

20-9

Page

20-14

20-15

20-16

20-7

20-18

10-4

20-19

16-2

16-2

9-5

9-4

14-14

14-17

9-7

11-4

9-5

9-4

5-26

17-1

18-7

17-3

16-1

Instruction- Description

MCR - Master Control Reset

MEQ - Mask Compare for Equal

MOV - Move

MSG - Message

MUL - Multiply

MVM - Masked Move

NEG - Negate

NEQ - Not Equal

NOT - Logical NOT

ONS - One Shot

OR - Logical OR

OSF - One Shot Falling

OSR - One Shot Rising

OTE - Output Energize

OTL - Output Latch

OTU - Output Unlatch

PID - Proportional Integral Derivative

PTO - Pulse Train Output

PWM - Pulse Width Modulation

RAC - Reset Accumulated Value

REF- I/O Refresh

RES - Reset

RET - Return from Subroutine

RTO - Retentive Timer, On-Delay

SBR - Subroutine Label

SCL - Scale

SCP - Scale with Parameters

SQC- Sequencer Compare

SQL - Sequencer Load

SQO- Sequencer Output

SQR - Square Root

STS - Selectable Timed Start

SUB - Subtract

SUS - Suspend

SWP - Swap

TND - Temporary End

TOD - Convert to Binary Coded Decimal (BCD)

TOF - Timer, Off-Delay

TON - Timer, On-Delay

UID - User Interrupt Disable


UIF - User Interrupt Flush


XIO - Examine if Open

XOR - Exclusive OR


8-6

16-3

10-7

10-8

15-2

15-8

15-5

10-9

7-4

19-3

6-1

6-18

5-27

17-4

8-10

16-3

7-6

7-6

7-3

7-4

9-3

12-6

7-5

12-4

Page

16-5

9-6

13-1

21-3

10-5

13-3

10-6

18-9

18-10

18-11

7-1

7-1

12-5

18-8

10-4

16-4

10-10

16-4

11-8

8-5

8-4


1

Supersedes Publication 1762-RM001B-US-P - April 2000

PN 40072-079-01(C)

© 2000 Rockwell International Corporation. Printed in the U.S.A.