Rockwell Automation 1756 ControlLogix, 1756 GuardLogix, 1769 CompactLogix, 1769 Compact GuardLogix, 1789 SoftLogix General Instructions

Reference Manual

Original Instructions

Logix 5000 Controllers General Instructions

1756 ControlLogix, 1756 GuardLogix, 1769 CompactLogix,
1769 Compact GuardLogix, 1789 SoftLogix, 5069
CompactLogix, Emulate 5570

Logix 5000 Controllers General Instructions

personal injury or death, property damage, or economic loss.

IMPORTANT

for Personal Protective Equipment (PPE).

Important User Information

Read this document and the documents listed in the additional resources section about installation, configuration, and
operation of this equipment before you install, configure, operate, or maintain this product. Users are required to familiarize
themselves with installation and wiring instructions in addition to requirements of all applicable codes, laws, and standards.

Activities including installation, adjustments, putting into service, use, assembly, disassembly, and maintenance are required to
be carried out by suitably trained personnel in accordance with applicable code of practice.

If this equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be
impaired.

In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use
or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and
requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for
actual use based on the examples and diagrams.

No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software
described in this manual.

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

Throughout this manual, when necessary, we use notes to make you aware of safety considerations.

WARNING: Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may lead to

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

Attentions help you identify a hazard, avoid a hazard, and recognize the consequence.

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

Labels may also be on or inside the equipment to provide specific precautions.

SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may be present.

BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach dangerous

temperatures.

ARC FLASH HAZARD: Labels may be on or inside the equipment, for example, a motor control center, to alert people to potential Arc Flash. Arc Flash
will cause severe injury or death. Wear proper Personal Protective Equipment (PPE). Follow ALL Regulatory requirements for safe work practices and

2 Publication 1756-RM003V-EN-P - November 2020

Topic Name

Reason

Added FBD Function element.

Added FBD Function element.

on page 478

and ULINT data types.

Added FBD Function element.

Added FBD Function element.

Equal To (EQU) on page 270

Updated the String Compare Flow Chart.

and ULINT data types.

and ULINT data types.

Summary of changes

This manual includes new and updated information. Use these reference
tables to locate changed information.

Global changes

The Legal noticeshave been updated.

New or enhanced features

This table contains a list of topics changed in this version, the reason for the
change, and a link to the topic that contains the changed information.

Arc Cosine (ACS) on page 705 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.
Added FBD Function element.

Bitwise And (AND) on page 413 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.
Added FBD Function element.

Arc Sine (ASN, ASIN) on page 711 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Arc Tangent (ATN, ATAN) on page 717 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Compare (CMP) on page 266 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.
Added support for logical operators &&, ||, ^^, and !.
Added support for IsINF and IsNAN.

Copy File (COP), Synchronous Copy File (CPS)

Cosine (COS) on page 723 Added support for LINT, LREAL, USINT, UINT, UDINT

Compute (CPT) on page 356 Removed condition statement for non-LREAL

Degrees (DEG) on page 773 Added support for LINT, LREAL, USINT, UINT, UDINT

File Arithmetic and Logic (FAL) on page 488 Added support for LINT, LREAL, USINT, UINT, UDINT

Convert to Integer (FRD) on page 769 Added support for LINT, LREAL, USINT, UINT, UDINT

Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

operands converting to LREAL.

and ULINT data types.

Publication 1756-RM003V-EN-P - November 2020 3

Summary of changes

Topic Name

Reason

Is Infinity (IsINF) on page 294

New instruction.

Is Not a Number (IsNAN) on page 296

New instruction.

Less Than or Equal To (LEQ) on page 306

Updated the String Compare Flow Chart.

Less Than (LES) on page 298

Updated the String Compare Flow Chart.

Added FBD Function element.

Not Equal To (NEQ) on page 333

Updated the String Compare Flow Chart.

Added FBD Function element.

Added FBD Function element.

Added FBD Function element.

and ULINT data types.

Added FBD Function element.

Added support for IsINF and IsNAN.

File Search and Compare (FSC) on page 513 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.
Added support for logical operators &&, ||, ^^, and !.

Added support for IsINF and IsNAN.

Greater Than or Equal To (GEQ) on page 286 Updated the String Compare Flow Chart.
Greater Than (GRT) on page 278 Updated the String Compare Flow Chart.

Natural Log (LN) on page 749 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Bitwise Not (NOT) on page 425 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Bitwise Inclusive Or (OR) on page 432 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Added FBD Function element.

Radian (RAD) on page 779 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Added FBD Function element.

Sine (SIN) on page 729 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Tangent (TAN) on page 735 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Convert to BCD (TOD) on page 764 Added support for LINT, LREAL, USINT, UINT, UDINT

Truncate (TRN) on page 785 Added support for LINT, LREAL, USINT, UINT, UDINT

and ULINT data types.

Valid operators on page 341 Added support for logical operators &&, ||, ^^, and !.

Determine Controller Memory Information on
page 182

Added a note to indicate that this section is not

applicable to CompactLogix 5380, CompactLogix

5480, ControlLogix 5580, Compact GuardLogix 5380,

and GuardLogix 5580 controllers.

4 Publication 1756-RM003V-EN-P - November 2020

Logix5000 Controllers General

Logix5000 Controllers Advanced Process

Logix5000 Controllers Motion Instructions

Add (ADD)

Attach to Equipment Phase (PATT)

Motion Apply Axis Tuning (MAAT)

Analog Alarm (ALMA)

Attach to Equipment Sequence (SATT)

Motion Apply Hookup Diagnostics (MAHD)

Arc Tangent (ATN, ATAN)

Derivative (DERV)

Motion Axis Fault Reset (MAFR)

ASCII Clear Buffer (ACL)

Detach from Equipment Sequence (SDET)

Motion Axis Home (MAH)

ASCII Handshake Lines (AHL)

Discrete 3-State Device (D3SD)

Motion Axis Jog (MAJ)

ASCII Read Line (ARL)

Enhanced PID (PIDE)

Motion Axis Position Cam (MAPC)

ASCII Test for Buffer Line (ABL)

Enhanced Select (ESEL)

Motion Axis Stop (MAS)

ASCII Write (AWT)

Equipment Phase Clear Failure (PCLF)

Motion Axis Time Cam (MATC)

ASCII Write Append (AWA)

Equipment Phase Command (PCMD)

Motion Axis Shutdown (MASD)

Bit Field Distribute (BTD)

Equipment Phase External Request (PXRQ)

Motion Axis Shutdown Reset (MASR)

Bit Field Distribute with Target (BTDT)

Equipment Phase Failure (PFL)

Motion Calculate Cam Profile (MCCP)

(POVR)

(MCTO)

Identifier (SASI)

Orientation (MCTPO)

Boolean AND (BAND)

Equipment Sequence command (SCMD)

Motion Change Dynamics (MCD)

Clear (CLR)

Integrator (INTG)

Motion Coordinated Stop (MCS)

Compare (CMP)

Internal Model Control (IMC)

Motion Coordinated Transform (MCT)

Convert to BCD (TOD)

JK Flip-Flop (JKFF)

Motion Direct Drive Off (MDF)

Convert to Integer (FRD)

Lead-Lag (LDLG)

Motion Direct Drive On (MDO)

Cosine (COS)

Maximum Capture (MAXC)

Motion Disarm Output Cam (MDOC)

Count down (CTD)

Modular Multivariable Control (MMC)

Motion Disarm Watch (MDW)

Instruction Locator

Use this locator to find the applicable Logix5000 controllers instruction
manual for each instruction.

Instructions Reference Manual 1756­RM003

Control and Drives and Equipment Phase
and Sequence Instructions Reference
Manual 1756-RM006

Reference Manual MOTION-RM002

Absolute Value (ABS) Alarm (ALM) Master Driven Coordinated Control (MDCC)

Always False (AFI) Coordinated Control (CC) Motion Arm Output Cam (MAOC)
Arc Cosine (ACS, ACOS) D Flip-Flop (DFF) Motion Arm Registration (MAR)

Arc Sine (ASN, ASIN) Deadtime (DEDT) Motion Arm Watch (MAW)

ASCII Chars in Buffer (ACB) Detach from Equipment Phase (PDET) Motion Axis Gear (MAG)

ASCII Read (ARD) Discrete 2-State Device (D2SD) Motion Axis Move (MAM)

Bit Shift Left (BSL) Equipment Phase New Parameters (PRNP) Motion Coordinated Path Move (MCPM)

Bit Shift Right (BSR) Equipment Phase Override Command

Motion Calculate Slave Values (MCSV)

Bitwise And (AND) Equipment Phase Paused (PPD) Motion Coordinated Transform with Orientation

Bitwise (NOT) Equipment Sequence Assign Sequence

Motion Calculate Transform Position (MCTP)

Bitwise (OR) Equipment Sequence Clear Failure (SCLF) Motion Calculate Transform Position with

Boolean Exclusive OR (BXOR) Equipment Sequence Override (SOVR) Motion Coordinated Change Dynamics (MCCD)
Boolean NOT (BNOT) Function Generator (FGEN) Motion Coordinated Circular Move (MCCM)

Boolean OR (BOR) High Pass Filter (HPF) Motion Coordinated Linear Move (MCLM)
Break (BRK) High/Low Limit (HLL) Motion Coordinated Shutdown (MCSD)
Breakpoints (BPT) HMI Button Control (HMIBC) Motion Coordinated Shutdown Reset (MCSR)

Copy File (COP), Synchronous Copy File (CPS) Low Pass Filter (LPF) Motion Direct Start (MDS)

Compute (CPT) Minimum Capture (MINC) Motion Disarm Registration (MDR)

Publication 1756-RM003V-EN-P - November 2020 5

Instruction Locator

Logix5000 Controllers General

Logix5000 Controllers Advanced Process

Manual 1756-RM006

Logix5000 Controllers Motion Instructions

Count up (CTU)

Moving Average (MAVE)

Motion Group Shutdown (MGSD)

Diagnostic Detect (DDT)

Phase State Complete (PSC)

Motion Redefine Position (MRP)

Digital Alarm (ALMD)

Position Proportional (POSP)

Motion Run Axis Tuning (MRAT)

End of Transition (EOT)

Process Dual Sensor Analog Input (PAID)

Motion Servo On (MSO)

FIFO Load (FFL)

Process Command Source (PCMDSRC)

File Average (AVE)

Process Discrete Input (PDI)

File Standard Deviation (STD)

Process Discrete Output (PDO)

File Fill (FLL)

Process Dosing (PDOSE)

File Sort (SRT)

Process Analog Fanout (PFO)

Find String (FIND)

Process High or Low Selector (PHLS)

For (FOR)

Process Interlocks (PINTLK)

(PLLS)

Value (SST)

Greater Than or Equal to (GEQ)

Process Permissives (PPERM)

(PPID)

Compensated Flow (PPTC)

Immediate Output (IOT)

Process Restart Inhibit (PRI)

Jump to Label (JMP) and Label (LBL)

Process Valve (PVLV)

and Return (RET)

Jump to External Routine (JXR)

Proportional + Integral (PI)

LIFO Unload (LFU)

Reset Dominant (RESD)

License Validation (LV)

Scale (SCL)

Limit (LIM)

S-Curve (SCRV)

Log Base (LOG)

Second-Order Controller (SOC)

Lower to Case (LOWER)

Second-Order Lead Lag (LDL2)

Masked Move (MVM)

Select (SEL)

Instructions Reference Manual 1756­RM003

Control and Drives and Equipment Phase
and Sequence Instructions Reference

Reference Manual MOTION-RM002

Count up/down CTUD Moving Standard Deviation (MSTD) Motion Group Shutdown Reset (MGSR)
Data Transition (DTR) Multiplexer (MUX) Motion Group Stop (MGS)
Degrees (DEG) Notch Filter (NTCH) Motion Group Strobe Position (MGSP)

DINT To String (DTOS) Process Analog HART (PAH) Motion Run Hookup Diagnostics (MRHD)
Divide (DIV) Process Analog Input (PAI) Motion Servo Off (MSF)

Equal to (EQU) Process Multi Sensor Analog Input (PAIM)
File Arithmetic (FAL) Process Analog Output (PAO)

File Bit Comparison (FBC) Process Boolean Logic (PBL)

FIFO Unload (FFU) Process Deadband Controller (PDBC)

File Search and Compare (FSC) Process Lead Lag Standby Motor Group

Get System Value (GSV) and Set System

Process Motor (PMTR)

Greater than (GRT) Process Proportional + Integral + Derivative

Insert String (INSERT) Process Pressure/Temperature

Is Infinity (IsINF) Process Run Time and Start Counter (PRT)
Is Not a Number (IsNAN) Process Tank Strapping Table (PTST)

Jump to Subroutine (JSR), Subroutine (SBR),

Process Valve Statistics (PVLVS)

Less Than (LES) Pulse Multiplier (PMUL)
Less Than or Equal to (LEQ) Ramp/Soak (RMPS)
LIFO Load (LFL) Rate Limiter (RLIM)

6 Publication 1756-RM003V-EN-P - November 2020

Masked Move with Target (MVMT) Selected Negate (SNEG)

Logix5000 Controllers General

Logix5000 Controllers Advanced Process

Manual 1756-RM006

Logix5000 Controllers Motion Instructions

Master Control Reset (MCR)

Selected Summer (SSUM)

Message (MSG)

Split Range Time Proportional (SRTP)

Middle String (MID)

Totalizer (TOT)

Modulo (MOD)

Up/Down Accumulator (UPDN)

Instruction Locator

Publication 1756-RM003V-EN-P - November 2020 7

Instructions Reference Manual 1756­RM003

Control and Drives and Equipment Phase
and Sequence Instructions Reference

Masked Equal to (MEQ) Set Dominant (SETD)

Move (MOV)
Multiply (MUL)
Natural Log (LN)
Negate (NEG)
Not Equal to (NEQ)
No Operation (NOP)
One Shot (ONS)
One Shot Falling (OSF)
One Shot Falling with Input (OSFI)
One Shot Rising (OSR)
One Shot Rising with Input (OSRI)
Output Energize (OTE)
Output Latch (OTL)
Output Unlatch (OTU)
Proportional Integral Derivative (PID)
Radian (RAD)
Real to String (RTOS)
Reset (RES)
Reset SFC (SFR)
Return (RET)
Retentive Timer On (RTO)
Retentive Timer On with Reset (RTOR)
Pause SFC (SFP)
Size In Elements (SIZE)
Sequencer Input (SQI)
Sequencer Load (SQL)
Sequencer Output (SQO)
Sine (SIN)
Square Roost (SQR/SQRT)
String Concatenate (CONCAT)
String Delete (DELETE)
String to DINT (STOD)
String to REAL (STOR)
Swap Byte (SWPB)
Subtract (SUB)
Tangent (TAN)
Timer Off Delay (TOF)
Timer Off Delay with Reset (TOFR)
Timer On Delay (TON)

Reference Manual MOTION-RM002

Instruction Locator

Logix5000 Controllers General

Logix5000 Controllers Advanced Process

Manual 1756-RM006

Logix5000 Controllers Motion Instructions

Enable (UIE)

Instructions Reference Manual 1756­RM003

Timer On Delay with Reset (TONR)
Temporary End (TND)
Tracepoints (TPT)
Trigger Event Task (EVENT)

Truncate (TRN)
Unknown Instruction (UNK)
Upper Case (UPPER)
User Interrupt Disable (UID)/User Interrupt

X to the Power of Y (XPY)
Examine if Closed (XIC)
Examine If Open (XIO)
Bitwise Exclusive (XOR)

Control and Drives and Equipment Phase
and Sequence Instructions Reference

Reference Manual MOTION-RM002

8 Publication 1756-RM003V-EN-P - November 2020

Summary of changes

Preface

Alarm Instructions

Bit Instructions

Timer and Counter Instructions

Input/Output

Table of Contents

Instruction Locator

Studio 5000 environment ......................................................................... 17

Additional resources .................................................................................. 18

Legal Notices .............................................................................................. 18

Chapter 1

Alarm Instructions ..................................................................................... 21

Analog Alarm (ALMA) ......................................................................... 22

Digital Alarm (ALMD) ......................................................................... 46

Alarm Set Operation (ASO) ................................................................ 58

Chapter 2

Bit Instructions .......................................................................................... 63

Examine If Closed (XIC) ...................................................................... 63

Examine If Open (XIO) ....................................................................... 66

One Shot (ONS) ................................................................................... 69

One Shot Falling (OSF) ........................................................................ 71

One Shot Falling with Input (OSFI) .................................................... 74

One Shot Rising (OSR) ........................................................................ 78

One Shot Rising with Input (OSRI) .................................................... 81

Output Energize (OTE) ....................................................................... 84

Output Latch (OTL) ............................................................................. 87

Output Unlatch (OTU) ........................................................................ 89

Publication 1756-RM003V-EN-P - November 2020 9

Chapter 3

Timer and Counter Instructions .............................................................. 93

Count Down (CTD) ............................................................................. 94

Count Up (CTU) ................................................................................... 99

Count Up/Down (CTUD) ................................................................... 104

Reset (RES) ......................................................................................... 109

Retentive Timer On (RTO) ................................................................. 112

Retentive Timer On with Reset (RTOR) ............................................117

Timer Off Delay (TOF) ....................................................................... 122

Timer Off Delay with Reset (TOFR) .................................................. 127

Timer On Delay (TON) ....................................................................... 132

Timer On Delay with Reset (TONR).................................................. 137

Chapter 4

Input/Output Instructions ...................................................................... 143

Message (MSG) ................................................................................... 143

MSG Configuration Examples .......................................................... 153

Table of Contents

Major fault types and codes ............................................................... 154

Minor fault types and codes .............................................................. 158

Message Error Codes ............................................................................... 161

Error Codes ............................................................................................... 161

Extended Error Codes ....................................................................... 162

PLC and SLC Error Codes (.ERR) ............................................................ 164

Block Transfer Error Codes ..................................................................... 165

Specify the Communication Details ................................................. 166

Specify SLC Messages ........................................................................ 174

Specify Block Transfer Messages ...................................................... 174

Get System Value (GSV) and Set System Value (SSV) ..................... 174

Immediate Output (IOT) ................................................................... 179

Access System Values ......................................................................... 182

Determine Controller Memory Information ................................... 182

DeviceNet Status Codes ..................................................................... 185

Get and Set System Data ................................................................... 188

GSV/SSV Programming Example ..................................................... 189

GSV/SSV Objects ................................................................................ 193

Access the AddOnInstructionDefinition Object ....................... 194

Access the ALARMBUFFER object .............................................. 195

Access the Axis object .................................................................. 197

Access the Controller object ....................................................... 205

Access the ControllerDevice object ............................................ 207

Access the CoordinateSystem object .......................................... 211

Access the MotionGroup object .................................................. 214

Access the Message object ........................................................... 215

Access the CST object................................................................... 215

Access the Datalog object ............................................................ 216

Access the DF1 object ................................................................... 218

Access the FaultLog object .......................................................... 220

Access the HardwareStatus object .............................................. 221

Access the Message object .......................................................... 222

Access the Module object ............................................................. 223

Access the Routine object ........................................................... 224

Access the Redundancy object ................................................... 225

Access the Program object ...........................................................227

Access the Safety object .............................................................. 228

Access the SerialPort object ....................................................... 229

Access the Task object ................................................................. 230

Access the TimeSynchronize object ........................................... 232

Access the WallClockTime object ............................................... 236

GSV/SSV Safety Objects .................................................................... 237

10 Publication 1756-RM003V-EN-P - November 2020

Compare Instructions

Compute/Math Instructions

Table of Contents

Monitor Status Flags .......................................................................... 241

Select the Message Type ................................................................... 242

Module Faults: 16#0000 - 16#00ff ..................................................... 243

Module Faults: 16#0100 - 16#01ff ....................................................... 245

Module Faults: 16#0200 - 16#02ff ..................................................... 249

Module Faults: 16#0300 - 16#03ff ..................................................... 250

Module Faults: 16#0800 - 16#08ff ...................................................... 253

Module Faults: 16#fd00 - 16#fdff ....................................................... 253

Module Faults: 16#fe00 - 16#feff ........................................................ 254

Module Faults: 16#ff00 - 16#ffff ......................................................... 256

Specify CIP Messages ........................................................................ 257

Specify PLC-3 Messages .................................................................... 262

Specify PLC-5 Messages .................................................................... 262

Specify PLC-2 Messages .................................................................... 263

Chapter 5

Compare Instructions ............................................................................. 265

Compare (CMP) ................................................................................. 266

Equal To (EQU) .................................................................................. 270

Greater Than (GRT) ........................................................................... 278

Greater Than or Equal To (GEQ) ...................................................... 286

Is Infinity (IsINF) .............................................................................. 294

Is Not a Number (IsNAN) ................................................................. 296

Less Than (LES) ................................................................................. 298

Less Than or Equal To (LEQ) ............................................................ 306

Limit (LIM) ......................................................................................... 315

Mask Equal To (MEQ) ........................................................................ 325

Not Equal To (NEQ) ........................................................................... 333

Valid operators ................................................................................... 341

What is zero fill? ................................................................................. 342

Publication 1756-RM003V-EN-P - November 2020 11

Chapter 6

Compute/Math Instructions ................................................................... 343

Absolute Value (ABS) ......................................................................... 344

Add (ADD) .......................................................................................... 350

Compute (CPT) ................................................................................... 356

Divide (DIV) ........................................................................................ 361

Modulo (MOD) ................................................................................... 368

Multiply (MUL) ................................................................................... 375

Negate (NEG) ..................................................................................... 381

Square Root (SQR/SQRT) .................................................................. 387

Subtract (SUB) .................................................................................... 394

Table of Contents

Move/Logical Instructions

Array (File)/Misc Instructions

FBD Functions ................................................................................... 400

Function Overloading ........................................................................ 401

Chapter 7

Move/Logical Instructions ..................................................................... 403

Bit Field Distribute (BTD) ................................................................ 404

Bit Field Distribute with Target (BTDT) .......................................... 408

Bitwise And (AND) ............................................................................. 413

Bitwise Exclusive Or (XOR) ............................................................... 419

Bitwise Not (NOT) .............................................................................. 425

Bitwise Inclusive Or (OR) .................................................................. 432

Boolean AND (BAND) ........................................................................ 439

Boolean Exclusive OR (BXOR) .......................................................... 444

Boolean NOT (BNOT) ....................................................................... 448

Boolean OR (BOR) .............................................................................. 452

Clear (CLR) .......................................................................................... 457

Masked Move (MVM) ........................................................................ 460

Masked Move with Target (MVMT) .................................................. 463

Move (MOV) ....................................................................................... 468

Swap Byte (SWPB) ............................................................................. 471

Chapter 8

Array (File)/Misc Instructions ................................................................ 477

Copy File (COP), Synchronous Copy File (CPS) ............................... 478

File Arithmetic and Logic (FAL) ....................................................... 488

File Average (AVE) ............................................................................. 506

File Fill (FLL) ....................................................................................... 510

File Search and Compare (FSC) ........................................................ 513

File Sort (SRT) .................................................................................... 528

File Standard Deviation (STD) .......................................................... 533

Size In Elements (SIZE) ..................................................................... 537

All Mode..................................................................................................... 542

All Mode Flow Chart (FSC) ................................................................ 543

Numerical Mode ................................................................................. 543

Numeric Mode Flow Chart (FSC) ...................................................... 545

Incremental Mode .............................................................................. 545

Incremental Mode Flow Chart (FSC) ................................................ 548

Array Tag ............................................................................................. 548

Standard Deviation ............................................................................ 548

12 Publication 1756-RM003V-EN-P - November 2020

Array (File)/Shift Instructions

Sequencer Instructions

Program Control Instructions

For/Break Instructions

Special Instructions

Table of Contents

Chapter 9

Array (File)/Shift Instructions ................................................................ 551

Bit Shift Left (BSL) ............................................................................. 552

Bit Shift Right (BSR) .......................................................................... 557

FIFO Load (FFL) .................................................................................. 561

FIFO Unload (FFU) .............................................................................568

LIFO Load (LFL) .................................................................................. 575

LIFO Unload (LFU) ............................................................................ 582

Chapter 10

Sequencer Instructions ........................................................................... 591

Sequencer Input (SQI) ....................................................................... 592

Sequencer Load (SQL) ....................................................................... 596

Sequencer Output (SQO) .................................................................. 600

Chapter 11

Program Control Instructions ............................................................... 608

Always False (AFI) ............................................................................. 609

End of Transition (EOT) .................................................................... 611

Jump to External Routine (JXR) ........................................................ 614

Jump to Label (JMP) and Label (LBL) ................................................ 617

Jump to Subroutine (JSR), Subroutine (SBR), and Return (RET) . 620

Master Control Reset (MCR) ............................................................ 630

MCR Flow Chart (False) ..................................................................... 633

No Operation (NOP) .......................................................................... 634

Pause SFC (SFP) ................................................................................. 636

Reset SFC (SFR) .................................................................................. 638

Temporary End (TND) ....................................................................... 641

Trigger Event Task (EVENT) ............................................................. 644

User Interrupt Disable (UID)/User Interrupt Enable (UIE) ........... 649

Unknown Instruction (UNK) ............................................................ 652

Publication 1756-RM003V-EN-P - November 2020 13

Chapter 12

For/Break Instructions ............................................................................ 655

Break (BRK) ........................................................................................ 655

For (FOR) ............................................................................................658

Chapter 13

Special Instructions ................................................................................. 663

Data Transition (DTR) ....................................................................... 664

Diagnostic Detect (DDT) ................................................................... 667

Table of Contents

Trigonometric Instructions

Advanced Math

Math Conversion Instructions

ASCII Serial Port Instructions

File Bit Comparison (FBC)................................................................. 675

Proportional Integral Derivative (PID) ............................................ 683

Using PID Instructions .............................................................. 689

Anti-reset Windup and Bumpless Transfer From Manual To

Auto (PID) ..................................................................................... 693

Bumpless Restart (PID) ............................................................... 694

Cascading Loops (PID) ................................................................ 694

Controlling a Ratio (PID) ............................................................ 695

Derivative Smoothing (PID) ....................................................... 697

Feedforward or Output Biasing (PID) ........................................ 697

PID Instruction Timing ............................................................... 697

Setting the Deadband (PID) ........................................................ 701

Using Output Limiting (PID) ..................................................... 702

Chapter 14

Trigonometric Instructions ................................................................... 704

Arc Cosine (ACS, ACOS) ................................................................... 705

Arc Sine (ASN, ASIN) ..........................................................................711

Arc Tangent (ATN, ATAN) ................................................................. 717

Cosine (COS) ...................................................................................... 723

Sine (SIN) ............................................................................................ 729

Tangent (TAN) .................................................................................... 735

Chapter 15

Advanced Math Instructions .................................................................. 743

Log Base 10 (LOG) .............................................................................. 743

Natural Log (LN) ................................................................................ 749

X to the Power of Y (XPY) .................................................................. 755

Chapter 16

Math Conversion Instructions ............................................................... 763

Convert to BCD (TOD) ....................................................................... 764

Convert to Integer (FRD) ................................................................... 769

Degrees (DEG) .................................................................................... 773

Radian (RAD) ...................................................................................... 779

Truncate (TRN) ................................................................................... 785

Chapter 17

ASCII Serial Port Instructions ................................................................ 793

ASCII Chars in Buffer (ACB) ............................................................. 795

ASCII Clear Buffer (ACL) ................................................................... 798

14 Publication 1756-RM003V-EN-P - November 2020

ASCII String Instructions

ASCII Conversion Instructions

Debug Instructions

License Instructions

Instructions

Table of Contents

ASCII Handshake Lines (AHL) ......................................................... 802

ASCII Read (ARD) ............................................................................. 806

ASCII Read Line (ARL) ....................................................................... 811

ASCII Test for Buffer Line (ABL) ....................................................... 816

ASCII Write (AWT) ........................................................................... 820

ASCII Write Append (AWA) ............................................................. 825

String Types ........................................................................................ 831

ASCII Error Codes .............................................................................. 831

Chapter 18

ASCII String Instructions ....................................................................... 833

Find String (FIND) ............................................................................. 834

Insert String (INSERT) ...................................................................... 837

Middle String (MID) ......................................................................... 840

String Concatenate (CONCAT) ......................................................... 843

String Delete (DELETE) .................................................................... 849

Common Attributes for General

Chapter 19

ASCII Conversion Instructions .............................................................. 853

DINT to String (DTOS) ...................................................................... 854

Lower Case (LOWER) ........................................................................ 857

REAL to String (RTOS) ..................................................................... 860

String to DINT (STOD) ..................................................................... 862

String to REAL (STOR) ..................................................................... 866

Upper Case (UPPER) ......................................................................... 869

Chapter 20

Debug Instructions .................................................................................. 873

Breakpoints (BPT) .............................................................................. 874

Tracepoints (TPT) .............................................................................. 878

Chapter 21

License Validation (LV) .......................................................................... 883

Chapter 22

Common Attributes ................................................................................ 887

Math Status Flags .................................................................................... 887

Immediate values .................................................................................... 889

Data Conversions .................................................................................... 890

Elementary data types .............................................................................. 893

Floating Point Values .............................................................................. 896

Publication 1756-RM003V-EN-P - November 2020 15

Table of Contents

Function Block Attributes

Structured Text Programming

Index

Index Through Arrays ............................................................................. 898

Bit Addressing ......................................................................................... 899

Chapter 23

Choose the Function Block Elements ..................................................... 901

Latching Data .......................................................................................... 902

Order of Execution .................................................................................. 903

Function Block Responses to Overflow Conditions ............................. 907

Timing Modes .......................................................................................... 907

Program/Operator Control ...................................................................... 910

Chapter 24

Structured Text Syntax ............................................................................ 915

Structured Text Components: Comments ............................................. 916

Structured Text Components: Assignments .......................................... 917

Specify a non-retentive assignment ................................................. 918

Assign an ASCII character to a string data member ....................... 919

Structured Text Components: Expressions .......................................... 920

Use arithmetic operators and functions .......................................... 921

Use bitwise operators ....................................................................... 922

Use logical operators ......................................................................... 922

Use relational operators .................................................................... 923

Structured Text Components: Instructions .......................................... 924

Structured Text Components: Constructs ............................................ 926

Character string literals .......................................................................... 926

String Types ........................................................................................ 927

CASE_OF .................................................................................................. 928

FOR_DO ................................................................................................... 930

IF_THEN ................................................................................................... 933

REPEAT_UNTIL ....................................................................................... 936

WHILE_DO ............................................................................................... 938

Structured Text Attributes ...................................................................... 940

16 Publication 1756-RM003V-EN-P - November 2020

Studio 5000 environment

Preface

This manual provides a programmer with details about the available General,
Motion, Process, and Drives instruction set for a Logix-based controller.

If you design, program, or troubleshoot safety applications that use
GuardLogix controllers, refer to the

Instruction Set Safety Reference Manual, publication 1756-RM095.

This manual is one of a set of related manuals that show common procedures
for programming and operating Logix 5000 controllers.

GuardLogix Safety Application

For a complete list of common procedures manuals, refer to the

Logix 5000
Controllers Common Procedures Programming Manual, publication 1756­PM001.

The term Logix 5000 controller refers to any controller based on the Logix
5000 operating system.

The Studio 5000 Automation Engineering & Design Environment® combines

engineering and design elements into a common environment. The first
element is the Studio 5000 Logix Designer® application. The Logix Designer
application is the rebranding of RSLogix 5000® software and will continue to
be the product to program Logix 5000™ controllers for discrete, process,
batch, motion, safety, and drive-based solutions.

Publication 1756-RM003V-EN-P - November 2020 17

The Studio 5000® environment is the foundation for the future of
Rockwell Automation® engineering design tools and capabilities. The Studio
5000 environment is the one place for design engineers to develop all
elements of their control system.

Preface

Resource

Description

http://ab.rockwellautomation.com

and other certification details.

Additional resources

Legal Notices

These documents contain additional information concerning related

Rockwell Automation products.

Industrial Automation Wiring and Grounding
Guidelines, publication 1770-4.1

Product Certifications webpage, available at

Provides general guidelines for installing a Rockwell
Automation industrial system.

Provides declarations of conformity, certificates,

View or download publications at

http://www.rockwellautomation.com/literature

. To order paper copies of
technical documentation, contact the local Rockwell Automation distributor
or sales representative.

Rockwell Automation publishes legal notices, such as privacy policies, license
agreements, trademark disclosures, and other terms and conditions on the

Legal Notices

page of the Rockwell Automation website.

End User License Agreement (EULA)

You can view the Rockwell Automation End-User License Agreement ("EULA")
by opening the License.rtf file located in your product's install folder on your
hard drive.

18 Publication 1756-RM003V-EN-P - November 2020

Open Source Licenses

The software included in this product contains copyrighted software that is
licensed under one or more open source licenses. Copies of those licenses are
included with the software. Corresponding Source code for open source
packages included in this product are located at their respective web site(s).

Alternately, obtain complete Corresponding Source code by contacting
Rockwell Automation via the Contact form on the Rockwell Automation
website:

us/contact/contact.page

Please include "Open Source" as part of the request text.

A full list of all open source software used in this product and their
corresponding licenses can be found in the OPENSOURCE folder. The default

http://www.rockwellautomation.com/global/about-

Preface

installed location of these licenses is C:\Program Files (x86)\Common

Files\Rockwell\Help\FactoryTalk Services Platform\Release

Notes\OPENSOURCE\index.htm

.

Publication 1756-RM003V-EN-P - November 2020 19

If:

Use the:

text,

conditions of the specified alarm set,

instruction.

Alarm Instructions

Chapter 1

Alarm Instructions

Use the alarm instructions to monitor and control alarm conditions.

The Logix-based alarm instructions instructions integrate alarming between

the RSView® SE applications and Logix 5000™ controllers.

Available Instructions

Ladder Diagram

ALMD ALMA ASO

Function Block

ALMD ALMA

Structured Text

ALMD ALMA ASO

Providing alarming for any discrete Boolean value
for a ladder diagram, function block, or structured

Providing level and rate-of-change alarming for
any analog signal for ladder diagram, function
block, diagram and structured text,

Issuing a specified operation to all alarm

Digital Alarm (ALMD)
instruction.

Analog Alarm (ALMA)
instruction.

Alarm Set Operation (ASO)

Publication 1756-RM003V-EN-P - November 2020 21

See also

Array (File)/Misc Instructions on page 477

ASCII Conversion Instructions on page 853

Chapter 1 Alarm Instructions

Analog Alarm (ALMA)

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers. Controller differences are noted where applicable.

The ALMA instruction provides level and rate-of-change alarming for any
analog signal.

Ladder Diagram

22 Publication 1756-RM003V-EN-P - November 2020

Operand

Type

Format

Description

ALMA

ALARM_ANALOG

Structure

ALMA structure

SINT

Function Block

Chapter 1 Alarm Instructions

Structured Text

ALMA (ALMA,In,ProgAckAll,ProgDisable,ProgEnable)

Operands

Ladder Diagram

In REAL

DINT
INT

ProgAckAll BOOL Tag

ProgDisable BOOL Tag

ProgEnable BOOL Tag

Tag
Immediate

Immediate

Immediate

Immediate

The alarm input value, which is
compared with alarm limits to
detect the alarm condition.

On transition from False to True,
acknowledges all alarm
conditions that require
acknowledgement.

When True, disables alarm (does
not override Enable Commands).

When True, enables alarm (takes
precedence over Disable
commands).

Publication 1756-RM003V-EN-P - November 2020 23

Chapter 1 Alarm Instructions

Operand

Type

Format

Description

Operand

Type

Format

Description

SINT

require acknowledgement.

Immediate

override Enable Commands).

Input Parameter

Data Type

Description

Default is set.

Copied from instruction operand.

Function Block

ALMA tag ALARM_ANALOG structure ALMA structure

Structured Text

ALMA ALARM_ANALOG Structure ALMA structure
In REAL

DINT
INT

Tag
Immediate

The alarm input value, which is
compared with alarm limits to detect
the alarm condition.

ProgAckAll BOOL Tag

Immediate

ProgDisable BOOL Tag

ProgEnable BOOL Tag

Immediate

On transition from False to True,
acknowledges all alarm conditions that

When True, disables alarm (does not

When True, enables alarm (takes
precedence over Disable commands).

See Structured Text Syntax for more information on the syntax of expressions
within the structured text.

ALMA Structure

Input Parameters

EnableIn BOOL Ladder Diagram:

Corresponds to the rung state. If false, the instruction does not execute
and outputs are not updated.

Structured Text:
If false, the instruction does not execute and outputs are not updated.
Default is set.
Function Block:
If false, the instruction does not execute and outputs are not updated.

24 Publication 1756-RM003V-EN-P - November 2020

In REAL The alarm input value, which is compared with alarm limits to detect the

alarm condition.
Default = 0.0.
Ladder Diagram:
Copied from instruction operand.
Structured Text:

Input Parameter

Data Type

Description

Default is false (good health).

Default is set.

Default is set.

Default is set.

Copied from the instruction operand.

Default is false.

Default is false.

Chapter 1 Alarm Instructions

InFault BOOL Bad health indicator for the input. The user application may set InFault to

indicate the input signal has an error. When set, the instruction sets
InFaulted (Status.1). When cleared to false, the instruction clears InFaulted
to false (Status.1). In either case, the instruction continues to evaluate In
for alarm conditions.

HHEnabled BOOL High High alarm condition detection. Set to true to enable detection of the

High High alarm condition. Clear to false to make detection unavailable for
the High High alarm condition.
Default is set.

HEnabled BOOL High alarm condition detection. Set to true to enable detection of the High

alarm condition. Clear to false to make detection unavailable for the High
alarm condition.

LEnabled BOOL Low alarm condition detection. Set to true to enable detection of the Low

alarm condition. Clear to false to make detection unavailable for the Low
alarm condition.

LLEnabled BOOL Low Low alarm condition detection. Set to true to enable detection of the

Low Low alarm condition. Clear to false to make detection unavailable for
the Low Low alarm condition.

AckRequired BOOL Specifies whether alarm acknowledgment is required. When set to true,

acknowledgment is required. When cleared to false, acknowledgment is
not required and HHAcked, HAcked, LAcked, LLAcked, ROCPosAcked, and
ROCNegAcked are always set to true
Default is true.

ProgAckAll BOOL Set to true by the user program to acknowledge all alarm conditions.

Takes effect only if any alarm condition is unacknowledged. Requires a
false-to-true transition.
Default is false.
Ladder Diagram:
Copied from the instruction operand.
Structured Text:

OperAckAll BOOL Set to true by the operator interface to acknowledge all alarm conditions.

Takes effect only if any alarm condition is unacknowledged. The alarm
instruction clears this parameter to false.

HHProgAck BOOL High High program acknowledge. Set to true by the user program to

acknowledge a High High condition. Takes effect only if the alarm
condition is unacknowledged. Requires a false -to-true transition.

Default is false.

HHOperAck BOOL High High operator acknowledge. Set to true by the operator interface to

acknowledge a High High condition. Takes effect only if the alarm
condition is unacknowledged. The alarm instruction clears this parameter
to false.

Publication 1756-RM003V-EN-P - November 2020 25

Chapter 1 Alarm Instructions

Input Parameter

Data Type

Description

Default is false.

Default is false.

Default is false.

Default is false.

Default is false.

Default is false.

Default is false.

Default is cleared.

Default is false.

HProgAck BOOL High program acknowledge. Set to true by the user program to

acknowledge a High condition. Takes effect only if the alarm condition is
unacknowledged. Requires a false-to-true transition.

HOperAck BOOL High operator acknowledge. Set to true by the operator interface to

acknowledge a High condition. Takes effect only if the alarm condition is
unacknowledged. The alarm instruction clears this parameter to false.

LProgAck BOOL Low program acknowledge. Set to true by the user program to

acknowledge a Low condition. Takes effect only if the alarm condition is
unacknowledged. Requires a false-to-true transition.

Default is false.

LOperAck BOOL Low operator acknowledge. Set to true by the operator interface to

acknowledge a Low condition. Takes effect only if the alarm condition is
unacknowledged. The alarm instruction clears this parameter to false.

LLProgAck BOOL Low Low program acknowledge. Set to true by the user program to

acknowledge a Low Low condition. Takes effect only if the alarm
condition is unacknowledged. Requires a false-to-true transition.

LLOperAck BOOL Low Low operator acknowledge. Set to true by the operator interface to

acknowledge a Low Low condition. Takes effect only if the alarm
condition is unacknowledged. The alarm instruction clears this parameter
false.

Default is false.

ROCPosProgAck BOOL Positive rate of change program acknowledge. Set to true by the user

program to acknowledge a positive rate-of-change condition. Requires a
false-to-true transition while the alarm condition is unacknowledged.

ROCPosOperAck BOOL Positive rate of change operator acknowledge. Set to true by the operator

interface to acknowledge a positive rate-of-change condition. Requires a
false-to-true transition while the alarm condition is unacknowledged. The
alarm instruction sets this parameter to false.

ROCNegProgAck BOOL Negative rate of change program acknowledge. Set to true by the user

program to acknowledge a negative rate-of-change condition. Requires a
false-to-true transition while the alarm condition is unacknowledged.

Default is false.

ROCNegOperAck BOOL Negative rate of change operator acknowledge. Set to true by the operator

interface to acknowledge a negative rate-of-change condition. Requires a
false-to-true transition while the alarm condition is unacknowledged. The
alarm instruction clears this parameter to false.

ProgSuppress BOOL Set to true by the user program to suppress the alarm.

OperSuppress BOOL Set to true by the operator interface to suppress the alarm. The alarm

instruction clears this parameter to false.

ProgUnsuppress BOOL Set to true by the user program to unsuppress the alarm. Takes

precedence over Suppress commands.
Default is false.

26 Publication 1756-RM003V-EN-P - November 2020

Input Parameter

Data Type

Description

Default is false.

again. It becomes unacknowledged when the shelve duration ends.

Unshelve commands take precedence over Shelve commands.

Unshelve commands take precedence over Shelve commands.

Unshelve commands take precedence over Shelve commands.

Default is false.

Chapter 1 Alarm Instructions

OperUnsuppress BOOL Set to true by the operator interface to unsuppress the alarm. Takes

precedence over Suppress commands. The alarm instruction sets this
parameter to false.

HHOperShelve BOOL High-high operator shelve. Set to true by the operator interface to shelve

or reshelve a high-high condition. Requires a false-to-true transition. The
alarm instruction clears this parameter to false.

Default is false.
Unshelve commands take precedence over Shelve commands.
Shelving an alarm postpones alarm processing. It is like suppressing an

alarm, except that shelving is time limited. If an alarm is acknowledged
while it is shelved, it remains acknowledged even if it becomes active

HOperShelve BOOL High operator shelve. Set to true by the operator interface to shelve or

reshelve a high condition. Requires a transition from false in one program
scan to true in the next program scan. The alarm instruction clears this
parameter to false.

Default is false.
Unshelve commands take precedence over Shelve commands.

LOperShelve BOOL Low operator shelve. Set to true by the operator interface to shelve or

reshelve a low condition. Requires a transition false in one program scan
to true in the next program scan. The alarm instruction clears this
parameter to false.

Default is false.

LLOperShelve BOOL Low-low operator shelve. Set to true by the operator interface to shelve or

reshelve a low-low condition. Requires a transition from false in one
program scan to true in the next program scan. The alarm instruction
clears this parameter to false.
Default is false.
Unshelve commands take precedence over Shelve commands.

ROCPosOperShelve BOOL Positive rate-of-change operator shelve. Set to true by the operator

interface to shelve or reshelve a positive rate-of-change condition.
Requires a transition from false in one program scan to true in the next
program scan. The alarm instruction clears this parameter to false.
Default is false.

ROCNegOperShelve BOOL Negative rate-of-change operator shelve. Set to true by the operator

interface to shelve or reshelve a negative rate-of-change condition.
Requires a transition from false in one program scan to true in the next
program scan. The alarm instruction clears this parameter to false.

Default is false.

ProgUnshelveAll BOOL Set to true by the user program to unshelve all conditions on this alarm. If

both shelve and unshelve are true, unshelve commands take precedence
over shelve commands.

HHOperUnshelve BOOL High-high operator unshelve. Set to true by the operator interface to

unshelve a high-high condition. The alarm instruction clears this
parameter to false. If both shelve and unshelve are true, unshelve
commands take precedence over shelve commands.

Default is false.

Publication 1756-RM003V-EN-P - November 2020 27

Chapter 1 Alarm Instructions

Input Parameter

Data Type

Description

Default is false.

Default is false.

Default is false.

Default is false.

Default is false.

ProgEnable

BOOL

Copied from the instruction operand.

Default is false.

Default is false.

Default is true.

HOperUnshelve BOOL High operator unshelve. Set to true by the operator interface to unshelve a

high condition. The alarm instruction clears this parameter to false. If
both shelve and unshelve are true, unshelve commands take precedence
over shelve commands.

LOperUnshelve BOOL Low operator unshelve. Set to true by the operator interface to unshelve a

low condition. The alarm instruction clears this parameter to false. If both
shelve and unshelve are true, unshelve commands take precedence over
shelve commands.

Default is false.

LLOperUnshelve BOOL Low-low operator unshelve. Set to true by the operator interface to

unshelve a low-low condition. The alarm instruction clears this parameter
to false. If both shelve and unshelve are true, unshelve commands take
precedence over shelve commands.

ROCPosOperUnshelve BOOL Positive rate-of-change operator unshelve. Set to true by the operator

interface to unshelve a positive rate-of-change condition. The alarm
instruction clears this parameter to false. If both shelve and unshelve are
set, unshelve commands take precedence over shelve commands.

ROCNegOperUnshelve BOOL Negative rate-of-change operator unshelve. Set to true by the operator

interface to unshelve a negative rate-of-change condition. The alarm
instruction clears this parameter to false. If both shelve and unshelve are
true, unshelve commands take precedence over shelve commands.

ProgDisable BOOL Copied from the instruction operand.
OperDisable BOOL Set to true by the operator interface to disable the alarm. The alarm

instruction clears this parameter to false.

OperEnable BOOL Set to true by the operator interface to enable the alarm. Takes

precedence over Disable command. The alarm instruction clears this
parameter false.

AlarmCountReset BOOL Set to true by the operator interface to reset the alarm counts for all

conditions. The alarm instruction clears this parameter to false.

HHMinDurationEnable BOOL High-high minimum duration enable. Set to true to enable minimum

duration timer when detecting the high-high condition.
Default is true.

HMinDurationEnable BOOL High minimum duration enable. Set to true to enable minimum duration

timer when detecting the high condition.
Default is true.

LMinDurationEnable BOOL Low minimum duration enable. Set to true to enable minimum duration

timer when detecting the low condition.

28 Publication 1756-RM003V-EN-P - November 2020

LLMinDurationEnable BOOL Low-low minimum duration enable. Set to true to enable minimum

duration timer when detecting the low-low condition.
Default is true.

Input Parameter

Data Type

Description

Default = 500.

Default = 0.0.

Default = 500.

Default = 0.0.

Default = 500.

Default = 500.

Chapter 1 Alarm Instructions

HHLimit REAL High High alarm limit.

Valid = HLimit < HHLimit < maximum positive float.
Default = 0.0.

HHSeverity DINT Severity of the High High alarm condition. This does not affect processing

of alarms by the controller, but can be used for sorting and filtering
functions at the alarm subscriber.

Valid = 1...1000 (1000 = most severe; 1 = least severe).

HLimit REAL High alarm limit.

Valid = LLimit < HLimit < HHLimit.

HSeverity DINT Severity of the High alarm condition. This does not affect processing of

alarms by the controller, but can be used for sorting and filtering
functions at the alarm subscriber.

Valid = 1...1000 (1000 = most severe; 1 = least severe).

LLimit REAL Low alarm limit.

Valid = LLLimit < LLimit < HLimit.

LSeverity DINT Severity of the Low alarm condition. This does not affect processing of

alarms by the controller, but can be used for sorting and filtering
functions at the alarm subscriber.

Valid = 1...1000 (1000 = most severe; 1 = least severe).

LLLimit REAL Low Low alarm limit.

Valid = maximum negative float < LLLimit < LLimit.
Default = 0.0.

LLSeverity DINT Severity of the Low Low alarm condition. This does not affect processing

of alarms by the controller, but can be used for sorting and filtering
functions at the alarm subscriber.
Valid = 1...1000 (1000 = most severe; 1 = least severe).

MinDurationPRE DINT Minimum duration preset (milliseconds) for an alarm level condition to

remain true before the condition is marked as InAlarm and alarm
notification is sent to clients. The controller collects alarm data as soon
as the alarm condition is detected; so no data is lost while waiting to meet
the minimum duration. Does not apply to rate-of-change conditions or to
conditions for which minimum duration detection is disabled.
MinDurationPRE only applies to the first excursion from normal in either
direction. For example, once the High condition times out, the High High
condition becomes active immediately, while a Low condition waits for
the timeout period.

Valid = 0...2147483647.
Default = 0.

ShelveDuration DINT Time duration (in minutes) for which a shelved alarm will be shelved.

Minimum time is one minute. Maximum time is defined by
MaxShelveDuration.

MaxShelveDuration DINT Maximum time duration (in minutes) for which an alarm can be shelved.

Publication 1756-RM003V-EN-P - November 2020 29

Chapter 1 Alarm Instructions

Input Parameter

Data Type

Description

Default = 0.0.

Default = 0.0.

Default = 500.

Default = 0.0.

Deadband REAL Deadband for detecting that High High, High, Low, and Low Low alarm

levels have returned to normal.
A non-zero Deadband can reduce alarm condition chattering if the In

value is continually changing but remaining near the level condition
threshold. The Deadband value does not affect the transition to the
InAlarm (active) state. Once a level condition is active, but before the
condition returns to the inactive (normal) state, the In value must either:

drop below the threshold minus the deadband (for High and High High
conditions).
OR

rise above the threshold plus the deadband (for Low and Low Low
conditions).

The Deadband is not used to condition the Minimum Duration time
measurement.

Valid = 0 = Deadband < Span from first enabled Low alarm to the first
enabled High alarm.

Default = 0.0.

ROCPosLimit REAL Limit for an increasing rate-of-change in units per second. Detection is

enabled for any value > 0.0 if ROCPeriod is also > 0.0.
Valid = 0.0...maximum possible float.

ROCPosSeverity DINT Severity of the increasing rate-of-change condition. This does not affect

processing of alarms by the controller, but can be used for sorting and
filtering functions at the alarm subscriber.
Valid = 1...1000 (1000 = most severe; 1 = least severe).
Default = 500.

ROCNegLimit REAL Limit for a decreasing rate-of-change in units per second. Detection is

enabled for any value > 0.0 if ROCPeriod is also > 0.0.
Valid = 0.0...maximum possible float.

ROCNegSeverity DINT Severity of the decreasing rate-of-change condition. This does not affect

processing of alarms by the controller, but can be used for sorting and
filtering functions at the alarm subscriber.

Valid = 1...1000 (1000 = most severe; 1 = least severe).

ROCPeriod REAL Time period in seconds for calculation (sampling interval) of the rate of

change value. Each time the sampling interval expires, a new sample of In
is stored, and ROC is re-calculated. Instead of an enable bit like other
conditions in the analog alarm, the rate-of-change detection is enabled by
putting any non-zero value in the ROCPeriod.

Valid = 0.0...32767.0

Output Parameters

These output parameters are common to ladder logic.

30 Publication 1756-RM003V-EN-P - November 2020

Output Parameter

Data Type

Description

Cleared to false when no Low condition exists.

Active. Cleared to false when no Low Low condition exists.

positive rate-of-change condition exists.

negative rate-of-change condition exists.

acknowledged.

Cleared to false when a High condition is not acknowledged.

rate-of-change condition is not acknowledged.

negative rate-of-change condition is not acknowledged.

acknowledged, or both.

Chapter 1 Alarm Instructions

AnyInAlarmUnack BOOL Combined alarm active and acknowledged status. Set to true when any

alarm condition is detected and unacknowledged. Cleared to false when
all alarm conditions are inactive, acknowledged, or both.

HHInAlarm BOOL High High alarm condition status. Set to true when a High High condition

is Active. Cleared to false when no High High condition exists.

HInAlarm BOOL High alarm condition status. Set to true when a High condition is Active.

Cleared to false when no High condition exists.

LInAlarm BOOL Low alarm condition status. Set to true when a Low condition is Active.

LLInAlarm BOOL Low Low alarm condition status. Set to true when a Low Low condition is

ROCPosInAlarm BOOL Positive rate-of-change alarm condition status. Set to true when a

positive rate-of-change condition exists. Cleared to false when no

ROCNegInAlarm BOOL Negative rate-of-change alarm condition status. Set to true when a

negative rate-of-change condition exists. Cleared to False when no

ROC REAL Calculated rate-of-change of the In value. This value is updated when

the instruction is scanned following each elapsed ROCPeriod. The ROC
value is used to evaluate the ROCPosInAlarm and ROCNegInAlarm
conditions.

ROC = (current sample of In – previous sample of In) / ROCPeriod

HHAcked BOOL High High condition acknowledged status. Set to true when a High High

condition is acknowledged. Always set to true when AckRequired is
cleared to false. Cleared to false when a High High condition is not

HAcked BOOL High condition acknowledged status. Set to true when a High condition is

acknowledged. Always set to true when AckRequired is cleared to false.

LAcked BOOL Low condition acknowledged status. Set to true when a Low condition is

acknowledged. Always set to true when AckRequired is cleared to false.
Cleared to false when a Low condition is not acknowledged.

LLAcked BOOL Low Low condition acknowledged status. Set to true when a Low Low

condition is acknowledged. Always true when AckRequired is cleared to
false. Cleared to false when a Low Low condition is not acknowledged.

ROCPosAcked BOOL Positive rate-of-change condition acknowledged status. Set to true

when a positive rate-of-change condition is acknowledged. Always true

when AckRequired is cleared to false. Cleared to false when a positive

ROCNegAcked BOOL Negative rate-of-change condition acknowledged status. Set to true

when a negative rate-of-change condition is acknowledged. Always set
to true when AckRequired is cleared to false. Cleared to false when a

HHInAlarmUnack BOOL Combined High High condition active and unacknowledged status. Set to

true when the High High condition is active (HHInAlarm is true) and
unacknowledged. Cleared to false when the High High condition is
inactive, acknowledged, or both.

HInAlarmUnack BOOL Combined High condition active and unacknowledged status. Set to true

when the High condition is active (HInAlarm is true) and
unacknowledged. Cleared to false when the High condition is inactive,

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Chapter 1 Alarm Instructions

Output Parameter

Data Type

Description

both.

inactive, acknowledged, or both.

positive rate-of-change condition is inactive, acknowledged, or both.

acknowledged, or both.

suppressed. Cleared to false when the alarm is not suppressed.

unshelved.

shelved. Cleared to false when high condition is unshelved.

shelved. Cleared to false when low condition is unshelved.

is shelved. Cleared to false when low-low condition is unshelved.

positive rate-of-change condition is unshelved.

MinDurationACC

DINT

Not Used. Value is always 0.

active state.

maximum count value.

active state.

LInAlarmUnack BOOL Combined Low condition active and unacknowledged status. Set to true

when the Low condition is active (LInAlarm is true) and unacknowledged.
Cleared to false when the Low condition is inactive, acknowledged, or

LLInAlarmUnack BOOL Combined Low Low condition active and unacknowledged status. Set to

true when the Low Low condition is active (LLInAlarm is true) and
unacknowledged. Cleared to false when the Low Low condition is

ROCPosInAlarmUnack BOOL Combined positive rate-of-change condition active and unacknowledged

status. Set to true when the positive rate-of-change condition is active
(ROCPosInAlarm is true) and unacknowledged. Cleared to false when the

ROCNegInAlarmUnack BOOL Combined negative rate-of-change condition active and

unacknowledged status. Set to true when the negative rate-of-change
condition is active (ROCNegInAlarm is true) and unacknowledged.
Cleared to false when the negative rate-of-change condition is inactive,

Suppressed BOOL Suppressed status of the alarm. Set to true when the alarm is

HHShelved BOOL High-high condition shelved status. Set to true when a high-high

condition is shelved. Cleared to false when high-high condition is

HShelved BOOL High condition shelved status. Set to true when a high condition is

LShelved BOOL Low condition shelved status. Set to true when a low condition is

LLShelved BOOL Low-low condition shelved status. Set to true when a low-low condition

ROCPosShelved BOOL Positive rate-of-change condition shelved status. Set to true when a

positive rate-of-change condition is shelved. Cleared to false when

ROCNegShelved BOOL Negative rate-of-change condition shelved status. Set to true when a

negative rate-of-change condition is shelved. Cleared to false when
negative rate-of-change condition is unshelved.

Disabled BOOL Disabled status of the alarm. Set to true when the alarm is unavailable

(disabled). Cleared to false when the alarm is enabled.

Commissioned BOOL The commissioned bit is not used.

HHInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

exceeded the High High condition limit for the most recent transition to
the active state.

HHAlarmCount DINT The number of times the High High condition has been activated. If the

maximum value is reached, the counter leaves the value at the
maximum count value.

HInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

exceeded the High condition limit for the most recent transition to the

HAlarmCount DINT The number of times the High condition has been activated. If the

LInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

32 Publication 1756-RM003V-EN-P - November 2020

maximum value is reached, the counter leaves the value at the

exceeded the Low condition limit for the most recent transition to the

Output Parameter

Data Type

Description

the active state.

maximum count value.

transition to the active state.

at the maximum count value.

condition alarm time.

RetToNormalTime

LINT

Timestamp of alarm returning to a normal state.

shelved the timestamp is set to current time.

Chapter 1 Alarm Instructions

LAlarmCount DINT The number of times the Low condition has been activated. If the

maximum value is reached, the counter leaves the value at the
maximum count value.

LLInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

exceeded the Low Low condition limit for the most recent transition to

LLAlarmCount DINT The number of times the Low Low condition has been activated. If the

maximum value is reached, the counter leaves the value at the

ROCPosInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

exceeded the positive-rate-of-change condition limit for the most recent

ROCPosInAlarmCount DINT The number of times the positive rate-of-change condition has been

activated. If the maximum value is reached, the counter leaves the value

ROCNegInAlarmTime LINT Timestamp when the ALMA instruction detected that the In value

exceeded the negative-rate-of-change condition limit for the most
recent transition to the active state.

ROCNegAlarmCount DINT The number of times the negative rate-of-change condition has been

activated. If the maximum value is reached, the counter leaves the value
at the maximum count value.

AckTime LINT Timestamp of most recent condition acknowledgment. If the alarm does

not require acknowledgment, this timestamp is equal to most recent

AlarmCountResetTime LINT Timestamp indicating when the alarm count was reset.
ShelveTime LINT Timestamp indicates when an alarm condition was shelved the last time.

Set by controller when alarm condition is shelved. Alarm conditions can
be shelved and unshelved many times. Each time alarm condition is

UnshelveTime LINT Timestamp indicating when all alarm conditions are going to be

unshelved. Value is set only when no alarm condition is shelved yet. The
timestamp is determined as sum of the ShelveDuration time period and
current time. If an alarm condition is unshelved programmatically or by
an operator and no other alarm condition is shelved, then value is set to
the current time.

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Chapter 1 Alarm Instructions

Output Parameter

Data Type

Description

InstructFault

Status.1 = InFaulted

X

X

Status.2 = SeverityInv

X

X

AlarmLimitsInv

ROCPosLimitInv

ROCNegLimitInv

If severity >1000, the instruction uses Severity = 1000.

fault is cleared, no new level conditions can be detected.

enabled high alarm.

= 0.0, which makes rate-of-change detection unavailable.

Compact GuardLogix 5380, and GuardLogix 5580 controllers only.

Status DINT Combined status indicators:

Status Flag CompactLogix 5370,

ControlLogix 5570,
Compact GuardLogix
5370, GuardLogix
5570 controllers

Status.0 =

CompactLogix
5380,
CompactLogix
5480, ControlLogix
5580, Compact
GuardLogix 5380,
and GuardLogix
5580 controllers

X X

Status.3 =

Status.4 =

X X

X X

DeadbandInv
Status.5 =

Status.6 =

Status.7 =

X X

X X

X X

ROCPeriodInv
Status.8 = Overflow - X

InstructFault (Status.0) BOOL Instruction error conditions exist. This is not a minor or major controller

error. Check the remaining status bits to determine what occurred.

InFaulted (Status.1) BOOL User program has set InFault to indicate bad quality input data. Alarm

continues to evaluate In for alarm conditions.

SeverityInv (Status.2) BOOL Alarm severity configuration is invalid.

If severity <1, the instruction uses Severity = 1.

AlarmLimitsInv (Status.3) BOOL Alarm Limit configuration is invalid (for example, LLimit < LLLimit). If

invalid, the instruction clears all level conditions active bits. Until the

DeadbandInv (Status.4) BOOL Deadband configuration is invalid. If invalid, the instruction uses

Deadband = 0.0.
Valid = 0 = Deadband < Span from first enabled low alarm to the first

34 Publication 1756-RM003V-EN-P - November 2020

ROCPosLimitInv (Status.5) BOOL Positive rate-of-change limit invalid. If invalid, the instruction uses

ROCPosLimit = 0.0, which makes positive rate-of-change detection

unavailable.

ROCNegLimitInv (Status.6) BOOL Negative rate-of-change limit invalid. If invalid, the instruction uses

ROCNegLimit = 0.0, which makes negative rate-of-change detection
unavailable.

ROCPeriodInv (Status.7) BOOL Rate-of-change period invalid. If invalid, the instruction uses ROCPeriod

Overflow
(Status.8)

BOOL The Overflow bit is set to true when an overflow condition is detected.

The overflow bit is cleared to false when the overflow condition has been
corrected.
Applies to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580,

Controllers

Affected Math Status Flags

controllers

GuardLogix 5370, GuardLogix 5570 controllers

A minor fault will occur if:

Fault Type

Fault Code

Chapter 1 Alarm Instructions

Connect a button to the OperShelve tag

The alarm instruction only processes the OperShelve tag on transition from
cleared to set to prevent unwanted reshelving of the alarm. For example, if an
operator presses a push button to shelve the alarm while the ProgUnshelve tag
is set, the alarm is not shelved because the ProgUnshelve tag takes
precedence. To shelve the alarm, the operator can release and press the push
button again once ProgUnshelve is cleared.

Affects Math Status Flags

CompactLogix 5380, CompactLogix 5480, ControlLogix
5580, Compact GuardLogix 5380, and GuardLogix 5580

CompactLogix 5370, ControlLogix 5570, Compact

Conditional

Yes

The input value is INF or NAN for CompactLogix 5370,
ControlLogix 5570, Compact GuardLogix 5370,
GuardLogix 5570 controllers only.

See Math Status Flags.

4 4

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array­indexing faults.

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Analog Alarm State Diagrams

These illustrations show the manner in which an analog alarm responds to
changing alarm conditions and operator commands.

Chapter 1 Alarm Instructions

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Chapter 1 Alarm Instructions

Publication 1756-RM003V-EN-P - November 2020 37

Chapter 1 Alarm Instructions

38 Publication 1756-RM003V-EN-P - November 2020

Chapter 1 Alarm Instructions

Analog Alarm Timing Diagrams

These timing diagrams show the sequence of analog alarm operations.

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Chapter 1 Alarm Instructions

Level Conditions Behavior Acknowledge

40 Publication 1756-RM003V-EN-P - November 2020

Level Conditions Behavior No Acknowledge

Chapter 1 Alarm Instructions

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Chapter 1 Alarm Instructions

ROC Conditions Behavior Acknowledge

42 Publication 1756-RM003V-EN-P - November 2020

Condition/State

Action Taken

Rung-condition-in is false

Rung-condition-out is cleared to false.

The instruction executes

ROC Conditions Behavior No Acknowledge

Chapter 1 Alarm Instructions

Execution

Ladder Diagram

Prescan Rung-condition-out is cleared to false.

All of the ALMA structure parameters are cleared
All alarm conditions are acknowledged.
All operator requests are cleared
All timestamps are cleared
All delivery flags are cleared.

Rung-condition-in is true Rung-condition-out is set to true

Postscan Rung-condition-out is cleared to false

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Chapter 1 Alarm Instructions

Condition/State

Action Taken

Postscan

Tag.EnableOut is cleared to false

Condition/State

Action Taken

Function Block

Prescan Tag.EnableOut is cleared to false.

All of the ALMA structure parameters are cleared
All alarm conditions are acknowledged.
All operator requests are cleared
All timestamps are cleared
All delivery flags are cleared.

Tag.EnableIn is false Tag.EnableOut is cleared to false
Tag.EnableIn is true The instruction executes

Tag.EnableOut is set to true
Instruction first run N/A
Instruction first scan N/A

Structured Text

In Structured Text, EnableIn is always true during normal scan. Therefore, if
the instruction is in the control path activated by the logic it will execute.

Prescan See Prescan in the Ladder Diagram table.
Normal Execution See Rung-condition-in is true in the Ladder

Diagram table.
Postscan See Postscan in the Ladder Diagram table.

Examples

Ladder Diagram

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Chapter 1 Alarm Instructions

Function Block

An example of an ALMA instruction in Function Block is shown below. In this
example, the Tank 32 Level Transmitter (Tank32LT) is monitored for alarm
conditions. The Tank32LevelAck tag can be used to acknowledge all conditions
of this alarm.

Structured Text

In this example, the Tank 32 Level Transmitter (Tank32LT) is monitored for
alarm conditions. The Tank32LevelAck tag can be used to acknowledge all
conditions of this alarm.

ALMA(Tank32Level,Tank32LT,Tank32LevelAck,0, 0);

See also

Structured Text Syntax on page 915

Math Status Flags on page 887

Index Through Arrays on page 898

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Chapter 1 Alarm Instructions

Digital Alarm (ALMD)

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The ALMD instruction provides alarming for any discrete Boolean value.

Available Languages

Ladder Diagram

Function Block

Structured Text

ALMD (ALMD,In,ProgAck,ProgReset,ProgDisable,ProgEnable)

46 Publication 1756-RM003V-EN-P - November 2020

Operand

Type

Format

Description

Immediate

acknowledgment is required).

Immediate

Immediate

Immediate

reported (milliseconds).

timer.

Operand

Type

Format

Description

Operand

Type

Format

Description

Immediate

acknowledgment is required).

Immediate

Operands

Ladder Diagram

ALMD tag ALARM_DIGITAL Structure ALMD structure
ProgAck BOOL Tag

On transition from false to true, acknowledges alarm (if

Chapter 1 Alarm Instructions

ProgReset BOOL Tag

ProgDisable BOOL Tag

ProgEnable BOOL Tag

MinDurationPRE DINT Immediate Specifies how long the alarm condition must be met before it is

MinDurationACC DINT Immediate Indicates the current accumulator value for the alarm’s MinDuration

On transition from false to true, resets alarm (if resetting is required).

When True, disables alarm (does not override Enable Commands).

When True, enables alarm (takes precedence over Disable commands).

Function Block

ALMD tag ALARM_DIGITAL structure ALMD structure

Structured Text

ALMD tag ALARM_DIGITAL Structure ALMD structure
ProgAck BOOL Tag

On transition from false to true, acknowledges alarm (if

Publication 1756-RM003V-EN-P - November 2020 47

ProgReset BOOL Tag

ProgDisable BOOL Tag

Immediate

ProgEnable BOOL Tag

Immediate

MinDurationPRE DINT Immediate Specifies how long the alarm condition must be met before it is

MinDurationACC DINT Immediate Indicates the current accumulator value for the alarm’s MinDuration

On transition from false to true, resets alarm (if resetting is required).

When True, disables alarm (does not override Enable Commands).

When True, enables alarm (takes precedence over Disable commands).

reported (milliseconds).

timer.

See Structured Text Syntax for more information on the syntax of expressions
within structured text.

Chapter 1 Alarm Instructions

Input Parameter

Data Type

Description

No effect. The instruction always executes.

Default is false (good health).

Default is true.

A latched alarm can only be reset when the alarm condition is false.

Copied from the instruction operand.

Default is false.

EnableIn BOOL Ladder Diagram:

In BOOL The digital signal input to the instruction.

InFault BOOL Bad health indicator for the input. The user application may set InFault to indicate the input

ALMD Structure

Input Parameters

Corresponds to the rung state. Does not affect processing.
Function Block:
If cleared to false, the instruction does not execute and outputs are not updated.
If set, the instruction executes.
Default is true.
Structured Text:

Default is false.
Ladder Diagram:
Follows the rung condition. Set to true if the rung condition is true. Cleared to false if the rung

condition is false.
Structured Text:
Copied from instruction operand.

signal has an error. When set, the instruction sets InFaulted (Status.1). When cleared to false,
the instruction clears the InFaulted (Status.1) to false. In either case, the instruction continues
to evaluate In for alarm conditions.

Condition BOOL Specifies how alarm is activated. When Condition is set to true, the alarm condition is

activated when In is set to true. When Condition is cleared to false, the alarm condition is
activated when In is Cleared to false.

AckRequired BOOL Specifies whether alarm acknowledgment is required. When set to true, acknowledgment is

required. When cleared to false, acknowledgment is not required and Acked is always set to
true.

Default is true.

Latched BOOL Specifies whether the alarm is latched. Latched alarms remain InAlarm when the alarm

condition becomes false, until a Reset command is received. When set to true, the alarm is
latched. When cleared to false, the alarm is unlatched.
Default is false.

ProgAck BOOL Set to true by the user program to acknowledge the alarm. Takes effect only if the alarm is

unacknowledged. Requires a false-to-true transition.
Default is false.
Ladder Diagram:
Copied from the instruction operand.
Structured Text:

OperAck BOOL Set to true by the operator interface to acknowledge the alarm. Takes effect only if the alarm

is unacknowledged. The instruction clears this parameter.

48 Publication 1756-RM003V-EN-P - November 2020

Input Parameter

Data Type

Description

Copied from the instruction operand.

Default is false.

Default is false.

Default is false.

duration ends provided the alarm is still active at that moment.

For more information on shelving an alarm, see the description for the OperShelve parameter.

For more information on shelving an alarm, see the description for the OperShelve parameter.

Copied from the instruction operand.

Chapter 1 Alarm Instructions

ProgReset BOOL Set to true by the user program to reset the latched alarm. Takes effect only if the latched

alarm is InAlarm and the alarm condition is false. Requires a false-to-true transition.
Default is false.
Ladder Diagram:
Copied from the instruction operand.
Structured Text:

OperReset BOOL Set to true by the operator interface to reset the latched alarm. Takes effect only if the latched

alarm is InAlarm and the alarm condition is false. The alarm instruction clears this parameter
to false.

Default is false.

ProgSuppress BOOL Set to true by the user program to suppress the alarm.

Default is false.

OperSuppress BOOL Set to true by the operator interface to suppress the alarm. The alarm instruction clears this

parameter to false.

ProgUnsuppress BOOL Set to true by the user program to unsuppress the alarm. Takes precedence over Suppress

commands.

OperUnsuppress BOOL Set to true by the operator interface to unsuppress the alarm. Takes precedence over

Suppress commands. The alarm instruction clears this parameter to false.

OperShelve BOOL Set to true by the operator interface to shelve or reshelve the alarm. Requires a transition from

false in one program scan to true in the next program scan. The alarm instruction clears this
parameter to false.
Default is false.
Unshelve commands take precedence over Shelve commands.
Shelving an alarm postpones alarm processing. It is like suppressing an alarm, except that
shelving is time limited. If an alarm is acknowledged while it is shelved, it remains
acknowledged even if it becomes active again. It becomes unacknowledged when the shelve

ProgUnshelve BOOL Set to true by the user program to unshelve the alarm. Takes precedence over Shelve

commands.
Default is false.

OperUnshelve BOOL Set to true by the operator interface to unshelve the alarm. The alarm instruction clears this

parameter to false. Takes precedence over Shelve commands.
Default is cleared.

ProgDisable BOOL Set to true by the user program to disable the alarm.

Default is false.
Ladder Diagram:
Copied from the instruction operand.
Structured Text:

OperDisable BOOL Set to true by the operator interface to disable the alarm. The alarm instruction clears this

parameter to true.
Default is false.

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Chapter 1 Alarm Instructions

Input Parameter

Data Type

Description

Copied from the instruction operand.

Default is false.

Default is false.

sequence-of-events input module.

Default = 500.

Default = 0.

Output Parameter

Data
Type

Description

EnableOut

BOOL

Enable output.

not active (normal status).

Acked is always set to true when AckRequired is cleared to false.

inactive, acknowledged, or both.

ProgEnable BOOL Set to true by the user program to enable the alarm. Takes precedence over a Disable

OperEnable BOOL Set to true by the operator interface to enable the alarm. Takes precedence over Disable

AlarmCountReset BOOL Set to true by the operator interface to reset the alarm count to zero. The alarm instruction

UseProgTime BOOL Specifies whether to use the controller’s clock or the ProgTime value to timestamp alarm state

ProgTime LINT If UseProgTime is set to true, this value is used to provide the timestamp value for all events.

command.
Default is false.
Ladder Diagram:
Copied from the instruction operand.
Structured Text:

command. The alarm instruction clears this parameter to false.

clears this parameter to false.
Default is false.

change events. When set to true, the ProgTime value provides timestamp. When cleared to
false, the controller’s clock provides timestamp.

This lets the application apply timestamps obtained from the alarm source, such as a

Severity DINT Severity of the alarm. This does not affect processing of alarms by the controller, but can be

used for sorting and filtering functions at the alarm subscriber.
Valid = 1...1000 (1000 = most severe; 1 = least severe).

MinDurationPRE DINT Minimum duration preset (milliseconds) for the alarm condition to remain true before the alarm

is marked as InAlarm and alarm notification is sent to clients. The controller collects alarm
data as soon as the alarm condition is detected; so no data is lost while waiting to meet the
minimum duration.
Valid = 0...2147483647.

ShelveDuration DINT Length of time in minutes to shelve an alarm. Shelving an alarm postpones alarm processing. It

is like suppressing an alarm, except that shelving is time limited. If an alarm is acknowledged
while it is shelved, it remains acknowledged even if it becomes active again. It becomes
unacknowledged when the shelve duration ends (provided the alarm is still active at that time).

Minimum time is one minute. Maximum time is defined by MaxShelveDuration.

MaxShelveDuration DINT Maximum time duration in minutes for which an alarm can be shelved. For more information on

shelving an alarm, see the description for the ShelveDuration parameter.

Output Parameters

InAlarm BOOL Alarm active status. Set to true when the alarm is active. Cleared to false when the alarm is

Acked BOOL Alarm acknowledged status. Set to true when the alarm is acknowledged. Cleared to false

InAlarmUnack BOOL Combined alarm active and acknowledged status. Set to true when the alarm is active

50 Publication 1756-RM003V-EN-P - November 2020

when the alarm is not acknowledged.

(InAlarm is true) and unacknowledged (Acked is false). Cleared to false when the alarm is

Output Parameter

Data

Description

duration ends.

the alarm is enabled.

false when the alarm is decommissioned. Currently always set to true.

MinDurationACC

DINT

Not used. Value is always 0.

reached, the counter leaves the value at the maximum count value.

InAlarmTime

LINT

Timestamp of alarm detection.

timestamp is equal to alarm time.

RetToNormalTime

LINT

Timestamp of alarm returning to a normal state.

AlarmCountResetTime

LINT

Timestamp indicating when the alarm count was reset.

For more information on shelving an alarm, see the description for the Shelved parameter.

For more information on shelving an alarm see the description for the Shelved parameter.

remaining status bits to determine what occurred.

(Status.1)

Chapter 1 Alarm Instructions

Type

Suppressed BOOL Suppressed status of the alarm. Set to true when the alarm is suppressed. Cleared to

falsewhen the alarm is not suppressed.

Shelved BOOL Shelved status of the alarm. Set to true when alarm is shelved. Cleared to false when alarm is

unshelved.
Shelving an alarm postpones alarm processing. It is like suppressing an alarm, except that

shelving is time limited. If an alarm is acknowledged while it is shelved, it remains
acknowledged even if it becomes active again. It becomes unacknowledged when the shelve

Disabled BOOL Disabled status of the alarm. Set to true when the alarm is not enabled. Cleared to false when

Commissioned BOOL Commissioned status of the alarm. Set to true when the alarm is commissioned. Cleared to

AlarmCount DINT Number of times the alarm has been activated (InAlarm is set). If the maximum value is

AckTime LINT Timestamp of alarm acknowledgment. If the alarm does not require acknowledgment, this

ShelveTime LINT Timestamp indicating when the alarm was shelved the last time. This value is set by

controller when alarm is shelved. Alarm can be shelved and unshelved many times. Each time
the alarm is shelved, the timestamp is set to the current time.

UnshelveTime LIN Timestamp indicating when the alarm is going to be unshelved. This value is set every time

the alarm is shelved (even if the alarm has already been shelved). The timestamp is
determined by adding the ShelveDuration to the current time. If the alarm is unshelved
programmatically or by an operator, then the value is set to the current time.

Status DINT Combined status indicators:

Status.0 = InstructFault
Status.1= InFaulted
Status.2 = SeverityInv

InstructFault (Status.0) BOOL Instruction error conditions exist. This is not a minor or major controller error. Check the

InFaulted

BOOL User program has set InFault to indicate bad quality input data. Alarm continues to evaluate

In for alarm condition.

SeverityInv
(Status.2)

BOOL Alarm severity configuration.

If severity <1, the instruction uses Severity = 1.
If severity >1000, the instruction uses Severity = 1000.

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Chapter 1 Alarm Instructions

Digital Alarms State Diagrams

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Digital Alarm Timing Diagrams

Chapter 1 Alarm Instructions

ALMD Alarm Acknowledge Required and Latched

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Chapter 1 Alarm Instructions

ALMD Alarm Acknowledge Required and Not Latched

ALMD Alarm Acknowledge Not Required and Latched

54 Publication 1756-RM003V-EN-P - November 2020

Chapter 1 Alarm Instructions

ALMD Alarm Acknowledge Not Required and Not Latched

Connect a button to the OperShelve tag

To prevent unwanted reshelving of the alarm, the alarm instruction only
processes the OperShelve tag if it transitions from false to true between one
program scan and the next. If an operator presses a push button to shelve the
alarm while the ProgUnshelve tag is true, the alarm is not shelved because the
ProgUnshelve tag takes precedence. However, because program scans
complete in milliseconds, the operator may still be holding down the push
button so that the OperShelve tag remains true over several program scans
even though the ProgUnshelve tag has been cleared to false. This means that
the alarm is not shelved.

To shelve the alarm, the operator can release and press the button again

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array­indexing faults.

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Chapter 1 Alarm Instructions

Condition/State

Action Taken

The instruction executes.

The instruction executes.

Postscan

Rung bit is cleared to false.

Condition/State

Action Taken

All timestamps are cleared

Tag.EnableIn is false

Tag.EnableOut is cleared to false

Tag.EnableOut is set to true

Condition/State

Action Taken

Prescan

See Prescan in the Ladder Diagram table.

Normal Execution

See Rung-condition-in is true in the Ladder Diagram table.

Prescan EnableOut is cleared to false to false

Rung-condition-in is false Rung is cleared to false.

Rung-condition-in is true Rung is set to true.

Execution

Ladder Diagram

The InAlarm output is cleared to false
The Shelved output is cleared to false
The Acked ouput is set to true.
All alarm conditions are acknowledged.
All operator requests are cleared
All timestamps are cleared

The In parameter is cleared to false

The In parameter is set to true

Function Block

Prescan Tag.EnableOut is cleared to false.

The InAlarm output is cleared to false
The Shelved output is cleared to false
The Acked ouput is set to true
All operator requests are cleared

Tag.EnableIn is true The instruction executes

Instruction first run N/A
Instruction first scan N/A

Postscan Tag.EnableOut is cleared to false.

Structured Text

Postscan See Postscan in the Ladder Diagram table.

56 Publication 1756-RM003V-EN-P - November 2020

Example

Ladder Diagram

Function Block

Chapter 1 Alarm Instructions

Structured Text

An example of an ALMD instruction in Structured Text is shown below. In this
example, two motor failure signals are combined such that if either one
occurs, a motor fault alarm is activated. The Motor101Ack tag can be used to
acknowledge the alarm.

Motor101FaultConditions := Motor101Overtemp OR Motor101FailToStart;

ALMD(Motor101Fault,Motor101FaultConditions,Motor101Ack,0,0
,0 );

See also

Structured Text Syntax on page 915

Math Status Flags on page 887

Publication 1756-RM003V-EN-P - November 2020 57

Chapter 1 Alarm Instructions

IMPORTANT

The .LastState structure member is modified by a user application program.

Alarm Set Operation (ASO)

Index Through Arrays on page 898

This information applies to the Compact GuardLogix 5380, CompactLogix

5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix 5580
controllers.

The Alarm Set Operation instruction issues a specified operation to all alarm
conditions of the specified alarm set. The Alarm Set Operation instruction is
used to initiate asynchronous execution of an alarm operation for all alarm
conditions of the specified alarm set. The instruction iterates through alarm
conditions of the specified alarm set and sets an internal flag requesting the
operation execution for each of the conditions. The internal flags have the
same purpose and priority as the existing user accessible Progxxx bits and will
be processed for all the alarm conditions of the specified alarm set during the
next periodic evaluation of each particular alarm condition from the set.

Available Languages

Ladder Diagram

Function Block Diagram

This instruction is not available in Function Block Diagram.

Structured Text

ASO (Alarm Set, Alarm Set Control, Operation)

Operands

Unexpected operation may occur if:

• The same tag (ALARM_SET_CONTROL) is used as a parameter for more than one
instruction invocation.

•

58 Publication 1756-RM003V-EN-P - November 2020

the controller mode from Program to Run for the changes to take effect.

Operand

Data Type

Format

Description

operated on by this instruction.

same priority as ProgXXX flags.

Condition/State

Action Taken

Prescan

The instruction clears all ALARM_SET structure members.

Rung-condition -in is false

The instruction clears .EnableOut and .LastState structure members.

always set to true.

ATTENTION: The Alarm Set Control structure contains internal state information. If any of the
configuration operands are changed while in run mode, accept the pending edits and cycle

Chapter 1 Alarm Instructions

The following table provides operands used for configuring the instruction.

Alarm Set ALARM_SET AlarmSet The ALARM_SET structure represents alarm conditions that are

Alarm Set Control ALARM_SET_CONTROL tag This data type contains three BOOL flags:

• EnableIn

• EnableOut

• LastState

The instruction reacts to the edge (transition of .EnableIn from
false to true) instead of the level.

EnableOut is always set to .EnableIn.
The request to perform the instruction operation have the

Operation

immediate This operand can be selected from the list or entered as an

integer value:
0 - Acknowledge
1 - Reset
2 - Enable
3 - Disable
4- Unshelve
5 - Suppress
6 - Unsuppress
7 - ResetAlarmCount

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array­indexing faults.

Execution

Rung-condition-in is true If .LastState is false then the instruction initiates the operation and sets

Postscan The instruction clears all ALARM_SET structure members.

Publication 1756-RM003V-EN-P - November 2020 59

.LastState structure member to true. The .EnableOut structure member is

Chapter 1 Alarm Instructions

Operation

The Alarm Set Operation instruction initiates asynchronous execution of one
of the following alarm operations on the specified alarm set:

• Acknowledge

• Reset

• Enable

• Disable

• Unshelve

• Suppress

• Unsuppress

• ResetAlarmCount

The instruction iterates through all alarm conditions which are included in
the specified alarm set or in the nested alarm sets to set an internal flag
representing the request to perform the required operation on a particular
alarm condition. The operation is initiated for all alarm conditions which are
iterated by the instruction with the following exceptions:

• Alarm Conditions which are configured not to support alarm
operations

• Alarm Conditions which are configured as not used

When an alarm operation is initiated for a particular alarm condition by the
instruction, the operation is performed during the next alarm periodic
evaluation of the alarm condition.

When the instruction is called multiple times for the same Alarm Set to
initiate contradictory alarm operations, the last requested operation is always
applied to all alarm conditions in the Alarm Set. The alarm operations
initiated for the Alarm Set may be applied to the conditions before the last
requested operation is performed.

When an Alarm Condition is periodically evaluated, the requests to perform
particular alarm operations have the same priority as the requests to perform
alarm operations initiated via user accessible Progxxx flags. It means that if a
request to perform an alarm operation is generated by the instruction, then it
is handled as if the corresponding Progxxx flag is set and the same rules used
to resolve conflicting requests specified for ProgXXX flags are used to resolve
conflicts between the instruction requests and requests made via Progxxx
flags.

The Alarm Set Operation instruction initiates the required alarm operation
only when it detects the transition of .EnableIn value from false to true. In
order to detect the transition, .LastState structure member is used to store
.EnableIn value from the previous instruction execution. See the Execution
section above.

60 Publication 1756-RM003V-EN-P - November 2020

conditions, then the execution time of the ASO instruction can increase significantly.

Tip: If the Alarm set provided as the instruction parameter contains an excessive number of alarm

See also

Alarm Instructions on page 21

Index Through Arrays (on page 898)

Chapter 1 Alarm Instructions

Publication 1756-RM003V-EN-P - November 2020 61

XIC

XIO

OTE

OTL

OTU

ONS

OSR

OSF

If you want to:

Use this instruction:

Enable outputs when a bit is set

XIC

Enable outputs when a bit is cleared

XIO

set a bit

OTE

clear bit (retentive)

OTU

goes true

set a bit for one scan each time a rung goes true

OSR

false

set in function block

cleared in function block

Bit Instructions

Examine If Closed (XIC)

Chapter 2

Bit Instructions

Use he bit (relay-type) instructions to monitor and control the status of bits,
such as input bits or timer-control word bits.

Available Instructions

Ladder Diagram

Function Block and Structured Text

OSRI OSFI

set a bit (retentive) OTL

Enable outputs for one scan each time a rung

set a bit for one scan each time the rung goes

set a bit for one scan each time the input bit is

set a bit for one scan each time the input bit is

ONS

OSF

OSRI

OSFI

Publication 1756-RM003V-EN-P - November 2020 63

See also

Compare Instructions on page 265

Compute/Math Instructions on page 343

Chapter 2 Bit Instructions

Operand

Data
Type

Format

Description

Addressing for examples.

This information applies to the CompactLogix 5370, ControlLogix 5570,
Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The XIC instruction examines the data bit to set or clear the rung condition.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Ladder Diagram

Data bit BOOL tag Bit to be tested. There are various operand

addressing modes possible for the data bit, see Bit

64 Publication 1756-RM003V-EN-P - November 2020

Affects Math Status Flags

No

Condition/State

Action Taken

Rung-condition-in is false

Set Rung-condition-out to Rung-condition-in

If DataBit is false, rung-condition-out is cleared to false.

Postscan

N/A

Chapter 2 Bit Instructions

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Prescan N/A

Rung-condition-in is true If DataBit is true, rung-condition-out is set to true.

Example 1

Ladder Diagram

If Limit_Switch_1 is true, the next instruction is enabled.

Example 2

Ladder Diagram

Publication 1756-RM003V-EN-P - November 2020 65

If S:V is true (generated by MOV), the next instruction is enabled.

Chapter 2 Bit Instructions

Examine If Open (XIO)

Example 3

Ladder Diagram

XIC Access LINT Number

Axis_04 is an AXIS_CIP_DRIVE tag.

Test_Axis_00 is an Alias for Axis_04.

The AXIS_CIP_DRIVE type has a LINT member called CIPAxisFaults.

BusUndervoltageULFault is a bit member of CIPAxisFaults.

Test_Axis_00.BusUndervoltageULFault is bit 34 of CIPAxisFaults. The bit 34
value is 0x400000000.

If Test_Axis_00.BusUndervoltageULFault is true, this enables the next
instruction.

See also

Bit Instructions on page 63

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

66 Publication 1756-RM003V-EN-P - November 2020

The XIO instruction examines the data bit to set or clear the rung condition.

Operand

Data Type

Format

Description

examples.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Chapter 2 Bit Instructions

Operands

Ladder Diagram

Data bit BOOL tag Bit to be tested. There are various

operand addressing modes possible
for the data bit, see Bit Addressing for

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Publication 1756-RM003V-EN-P - November 2020 67

Chapter 2 Bit Instructions

Condition/State

Action Taken

Prescan

N/A

If Data Bit is false, rung-condition-out is set to true.

Postscan

N/A

Execution

Ladder Diagram

Rung-condition-in is false Set Rung-condition-out to Rung-condition-in
Rung-condition-in is true If Data Bit is true, rung-condition-out is cleared to

false.

Examples

Example 1

Ladder Diagram

If Limit_Switch_01 is false, the next instruction is enabled.

Example 2

Ladder Diagram

68 Publication 1756-RM003V-EN-P - November 2020

If S:V is false, this enables the next instruction.

See also

Bit Instructions on page 63

IMPORTANT

Operand

Data Type

Format

Description

One Shot (ONS)

Chapter 2 Bit Instructions

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The ONS instruction makes the remainder of the rung true each time rung­condition-in transitions from false to true.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

•

Except when specified, structure operands are shared by multiple instructions.

Publication 1756-RM003V-EN-P - November 2020 69

Ladder Diagram

Chapter 2 Bit Instructions

Condition/State

Action Taken

trigger during the first scan.

Storage bit BOOL tag Internal storage bit.

Retains the rung-condition-in from
the last time the instruction was
executed.

There are various operand
addressing modes possible for the
storage bit, see Bit Addressing for
examples.

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Prescan The storage bit is set to true to prevent an invalid

Rung-condition-in is false The storage bit is cleared to false, rung-condition-

out is cleared to false.

Rung-condition-in is true See ONS Flow Chart (True).
Postscan N/A

70 Publication 1756-RM003V-EN-P - November 2020

One Shot Falling (OSF)

ONS Flow Chart (True)

Chapter 2 Bit Instructions

Example

Ladder Diagram

In this example, the sum increments each time limit_switch_1 goes from false
to true.

See also

Bit Instructions on page 63

Publication 1756-RM003V-EN-P - November 2020 71

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

Chapter 2 Bit Instructions

IMPORTANT

Operand

Data Type

Format

Description

The OSF instruction sets the output bit for one scan when rung-condition-in
transitions from true to false.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

•

Except when specified, structure operands are shared by multiple instructions.

Ladder Diagram

Storage Bit BOOL tag Stores the rung-condition-in from

when the instruction was last
executed.
There are various operand addressing
modes possible for the storage bit, see
Bit Addressing for examples.

Output Bit BOOL tag Bit to be modified.

72 Publication 1756-RM003V-EN-P - November 2020

Condition/State

Action Taken

Chapter 2 Bit Instructions

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Prescan The storage bit is cleared to false to prevent an

invalid trigger during the first program scan.
The output bit is cleared to false.

Rung-condition-in is false Set Rung-condition-out to Rung-condition-in.

See OSF Flow Chart (False).

Rung-condition-in is true Set Rung-condition-out to Rung-condition-in.

The storage bit is set to true.
The output bit is cleared to false.

Postscan N/A

OSF Flow Chart (False)

Publication 1756-RM003V-EN-P - November 2020 73

Chapter 2 Bit Instructions

One Shot Falling with Input

Example

Ladder Diagram

This example shows how an OSF can be used to make one or more
instructions edge-triggered. Each time Limit_Switch_01 transitions from true
to false the OSF will set Output_bit_02 to true. Any instruction conditioned by
Output_bit_02 will be enabled and, since Output_bit_02 is only true for one
scan, will execute once per transition.

(OSFI)

See also

Bit Instructions on page 63

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,

CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The OSFI instruction sets the OutputBit for one execution cycle when the
InputBit toggles from false to true.

74 Publication 1756-RM003V-EN-P - November 2020

Operand

Type

Format

Description

OSFI tag

FBD_ONESHOT

Structure

OSFI structure

Operand

Type

Format

Description

OSFI tag

FBD_ONESHOT

Structure

OSFI structure

Input

Data Type

Description

Available Languages

Ladder Diagram

This instruction is not available in ladder diagram.

Function Block

Chapter 2 Bit Instructions

Structured Text

OSFI(OSFI_tag)

Operands

Structured Text

See Structured Text Syntax for operand-related faults

Function Block

FBD_ONESHOT Structure

Parameter

EnableIn BOOL Enable input. If cleared, the instruction does

not execute and outputs are not updated.
Default is set.

InputBit BOOL Input bit.

Publication 1756-RM003V-EN-P - November 2020 75

Chapter 2 Bit Instructions

Output Parameter

Data Type

Description

EnableOut

BOOL

Indicates if instruction is enabled.

OutputBit

BOOL

Output bit

Condition / State

Action Taken

Prescan

EnableIn and EnableOut bits are cleared to false.

Description

If InputBit is false, and it was true the last time the instruction was scanned
then OutputBit will be set, otherwise OutputBit will be cleared.

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Common Attributes for operand-related
faults.

Execution

Function Block

76 Publication 1756-RM003V-EN-P - November 2020

Tag.EnableIn is false EnableIn and EnableOut bits are cleared to false.
Tag.EnableIn is true EnableIn and EnableOut bits are set to true.

The instruction executes

Condition / State

Action Taken

Instruction first run

N/A

False transition of InputBit.

Postscan

EnableIn and EnableOut bits are cleared to false.

Condition / State

Action Taken

Instruction first scan Previous InputBit history is cleared to require a True to

Chapter 2 Bit Instructions

Structured Text

Prescan See Prescan in the Function Block table.
Normal execution See Tag.EnableIn is true in the Function Block table.

Postscan See Postscan in the Function Block table.

Example

When limit_switch1 goes from set to cleared, the OSFI instruction sets
OutputBit for one scan.

Function Block

Structured Text

OSFI_01.InputBit := limit_switch1;

OSFI(OSFI_01);

Output_state := OSFI_01.OutputBit;

See also

Publication 1756-RM003V-EN-P - November 2020 77

Bit Instructions on page 63

OSF on page 71

Common Attributes on page 887

Chapter 2 Bit Instructions

IMPORTANT

• Except when specified, structure operands are shared by multiple instructions.

Operand

Data Type

Format

Description

One Shot Rising (OSR)

Structured Text Syntax on page 915

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The OSR instruction sets the output bit for one scan when rung-condition-in
transitions from false to true.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

Ladder Diagram

78 Publication 1756-RM003V-EN-P - November 2020

Bit Addressing for examples.

Output Bit

BOOL

tag

Bit to be modified.

Condition/State

Action Taken

The output bit is cleared to false.

Storage Bit BOOL tag Stores the rung-condition-in from

when the instruction was last
executed.
There are various operand addressing
modes possible for the storage bit, see

Chapter 2 Bit Instructions

Description

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Publication 1756-RM003V-EN-P - November 2020 79

Prescan The storage bit is set to true to prevent an invalid trigger during the

first program scan.

Rung-condition-in is false Set Rung-condition-out to Rung-condition-in

The storage bit is cleared to false.
The output bit is cleared to false.

Chapter 2 Bit Instructions

Rung-condition-in is true Set Rung-condition-out to Rung-condition-in

See OSR Flow Chart (True).

Postscan N/A

OSR Flow Chart (True)

Example

Ladder Diagram

This example shows how an OSR can be used to make one or more
instructions edge-triggered. Each time Limit_Switch_01 transitions from
false to true the OSR will set Output_bit_02 to true. Any instruction

80 Publication 1756-RM003V-EN-P - November 2020

One Shot Rising with Input

(OSRI)

conditioned by Output_bit_02 will be enabled and, since Output_bit_02 is
only true for one scan, will execute once per transition.

Chapter 2 Bit Instructions

See also

Bit Instructions on page 63

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,

CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The OSRI instruction sets the output bit for one execution cycle when the
input bit toggles from cleared to set.

Available Languages

Ladder Diagram

This instruction is not available in ladder diagram.

Function Block

Publication 1756-RM003V-EN-P - November 2020 81

Structured Text

OSRI(OSRI_tag);

Chapter 2 Bit Instructions

Operand

Type

Format

Description

OSRI tag

FBD_ONESHOT

Structure

OSRI structure

Operand

Type

Format

Description

OSRI tag

FBD_ONESHOT

Structure

OSRI structure

Input

Data Type

Description

Default is set.

Default is cleared.

Operands

Structured Text

Function Block

FBD_ONESHOT Structure

Parameter

EnableIn BOOL If cleared, the instruction does not

execute and outputs are not updated.
If set, the instruction executes.

InputBit BOOL Input bit.

Output
Parameter

EnableOut BOOL Indicates if instruction is enabled.
OutputBit BOOL Output bit

Data Type Description

Description

If InputBit is true, and it was false the last time the instruction was scanned
then OutputBit will be set, otherwise OutputBit will be cleared.

82 Publication 1756-RM003V-EN-P - November 2020

Condition/State

Action Taken

Prescan

EnableIn and EnableOut bits are cleared to false.

Tag.Enable-in is false

EnableIn and EnableOut bits are cleared to false.

The instruction executes.

to True transition of InputBit.

Condition/State

Action Taken

Prescan

See Prescan in the Function Block table.

Affects Math Status Flags

No

Chapter 2 Bit Instructions

Major/Minor Faults

None specific to this instruction. See Common Attributes for operand-related
faults.

Execution

Function Block

Tag.Enable-in is true EnableIn and EnableOut bits are set to true.

Instruction first run N/A
Instruction first scan Previous InputBit history is set to require a False

Postscan EnableIn and EnableOut bits are cleared to false.

Publication 1756-RM003V-EN-P - November 2020 83

Structured Text

Chapter 2 Bit Instructions

Output Energize (OTE)

Normal execution See Tag.EnableIn is true in the the Function Block

table.

Postscan See Postscan in the Function Block table

Examples

Function Block

When limit_switch1 goes from cleared to set, the OSRI instruction sets
OutputBit for one scan.

Structured Text

OSRI_01.InputBit := limit_switch1;

OSRI(OSRI_01);

State := OSRI_O1.OutputBit;

See also

Bit Instructions on page 63

One Shot Falling (OSF) on page 71

One Shot (ONS) on page 69

Common Attributes on page 887

Structured Text Syntax on page 915

84 Publication 1756-RM003V-EN-P - November 2020

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,

IMPORTANT

Except when specified, structure operands are shared by multiple instructions.

Operand

Data Type

Format

Description

Chapter 2 Bit Instructions

CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The OTE instruction sets or clears the data bit based on rung condition.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

•

Ladder Diagram

Data bit BOOL tag Bit to be modified. There are

various operand addressing
modes possible for the data bit,
see Bit Addressing for examples.

Publication 1756-RM003V-EN-P - November 2020 85

Chapter 2 Bit Instructions

Condition/State

Action Taken

Postscan

The data bit is cleared to false.

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Prescan The data bit is cleared to false
Rung-condition-in is false Set Rung-condition-out to Rung-condition-in.

The data bit is cleared to false

Rung-condition-in is true Set Rung-condition-out to Rung-condition-in.

The data bit is set to true.

Example

Ladder Diagram

When switch is true, the OTE instruction sets Light_01 to true. When switch is
false, the OTE instruction clears Light_01 to false.

See also

Structured Text Syntax on page 915

Bit Instructions on page 63

Bit Addressing on page 899

86 Publication 1756-RM003V-EN-P - November 2020

Index Through Arrays on page 898

IMPORTANT

• Except when specified, structure operands are shared by multiple instructions.

Operand

Data Type

Format

Description

examples.

Output Latch (OTL)

Chapter 2 Bit Instructions

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers. Controller differences are noted where applicable.

The OTL instruction sets (latches) the data bit.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

Ladder Diagram

Data bit BOOL tag Bit to be modified. There are

various operand addressing
modes possible for the data
bit, see Bit Addressing for

Publication 1756-RM003V-EN-P - November 2020 87

Chapter 2 Bit Instructions

Condition/State

Action Taken

The data bit is set to true.

Postscan

N/A

Description

When the rung condition is true, the OTL instruction sets the data bit to true.
The data bit remains true until it is cleared, typically by an OTU instruction.
When the rung condition is changed to false, the OTL instruction does not
change the status of the data bit.

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

For Compact GuardLogix 5380, CompactLogix 5380, CompactLogix 5480,
ControlLogix 5580, and GuardLogix 5580 controllers, if the operand is an
indirect array reference and the subscript is out of range, then the controller
does not generate a major fault when the OTL instruction is false.

Execution

Ladder Diagram

Prescan N/A
Rung-condition-in is false Set Rung-condition-out to Rung-

condition-in.

Rung-condition-in is true Set Rung-condition-out to Rung-

condition-in.

88 Publication 1756-RM003V-EN-P - November 2020

Example

Ladder Diagram

Output Unlatch (OTU)

When enabled, the OTL instruction turns the light on.

Chapter 2 Bit Instructions

See also

Structured Text Syntax on page 915

Bit Instructions on page 63

Bit Addressing on page 899

Index Through Arrays on page 898

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The OTU instruction clears (unlatches) the data bit.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

Publication 1756-RM003V-EN-P - November 2020 89

This instruction is not available in structured text.

Chapter 2 Bit Instructions

IMPORTANT

Operand

Data Type

Format

Description

Rung-condition-in is false

Set Rung-condition-out to Rung-condition-in

The data bit is cleared to false.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

•

Except when specified, structure operands are shared by multiple instructions.

Ladder Diagram

Data bit BOOL tag Bit to be modified. There are

various operand addressing
modes possible for the data
bit, see Bit Addressing for
examples.

Description

When the rung condition is true, the OTU instruction clears the data bit to
false. When the rung condition is changed to false, the OTU instruction does
not change the status of the data bit.

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array-indexing
faults.

Execution

Ladder Diagram

Condition/State Action Taken

Prescan N/A

Rung-condition-in is true Set Rung-condition-out to Rung-condition-in

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Postscan N/A

Example

Ladder Diagram

When enabled, the OTU instruction clears Light_02.

See also

Bit Instructions on page 63

Bit Addressing on page 899

Index Through Arrays on page 898

Chapter 2 Bit Instructions

Publication 1756-RM003V-EN-P - November 2020 91

TON

TOF

RTO

CTU

CTD

RES

If you want to

Use this instruction

time how long a timer is enabled

TON

time how long a timer is disabled

TOF

accumulate time

RTO

built-in reset in function block

with built-in reset in function block

function block

count up

CTU

Timer and Counter

Instructions

Chapter 3

Timer and Counter Instructions

Timers and counters control operations based on time or the number of

events.

Available Instructions

Ladder Diagram

Function Block and Structured Text

TONR TOFR RTOR CTUD

time how long a timer is enabled with

time how long a timer is disabled

accumulate time with built-in reset in

count down CTD
count up and count down in function

block
reset a timer or counter RES

The time base is 1 msec for all timers. For example, a 2 second timer’s .PRE
value should be 2000.

TONR

TOFR

RTOR

CTUD

Publication 1756-RM003V-EN-P - November 2020 93

See also

Compute/Math Instructions on page 343

Chapter 3 Timer and Counter Instructions

IMPORTANT

Count Down (CTD)

Compare Instructions on page 265

Bit Instructions on page 63

ASCII String Instructions on page 833

ASCII Conversion Instructions on page 853

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

The CTD instruction counts downward each time the rung-condition-in
transitions from false to true.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

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Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

•

Except when specified, structure operands are shared by multiple instructions.

Operand

Data Type

Format

Description

Accum

DINT

immediate

Value of Counter.ACC.

Mnemonic

Data Type

Description

executed.

operation is complete.

instruction indicates it is done.

Chapter 3 Timer and Counter Instructions

Ladder Diagram

Counter COUNTER tag Counter structure
Preset DINT immediate Value of Counter.PRE.

COUNTER Structure

.CD BOOL The countdown enable bit contains rung-

condition-in when the instruction was last

.DN BOOL The done bit when clear indicates the counting

.OV BOOL The overflow bit when set indicates the counter

incremented past the upper limit of 2,147,483,647.

.UN BOOL The underflow when set indicates the counter

decremented past the lower limit of -2,147,483,648.

.PRE DINT The preset value specifies the value which the

accumulated value must reach before the

.ACC DINT The accumulated value specifies the number of

transitions the instruction has counted.

Description

The CTD instruction is typically used with a CTU instruction that references
the same counter structure.

When rung-condition-in is set to true and .CD is false, .ACC will be
decremented by one. When rung-condition-in is false, .CD will be cleared to
false.

Publication 1756-RM003V-EN-P - November 2020 95

Chapter 3 Timer and Counter Instructions

Condition/State

Action Taken

Affects Math Status Flags

No

Major/Minor Faults

None specific to this instruction. See Index Through Arrays for array­indexing faults.

Execution

Ladder Diagram

Prescan The .CD bit is set to true to prevent invalid decrements during the first

program scan.

Rung-condition-in is false Set Rung-condition-out to Rung-condition-in

See CTD Flow Chart (False)

Rung-condition-in is true Set Rung-condition-out to Rung-condition-in

See CTD Flow Chart (True)

Postscan N/A

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CTD Flow Chart (False)

Chapter 3 Timer and Counter Instructions

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Chapter 3 Timer and Counter Instructions

CTD Flow Chart (True)

98 Publication 1756-RM003V-EN-P - November 2020

Count Up (CTU)

Example

Ladder Diagram

Chapter 3 Timer and Counter Instructions

A conveyor brings parts into a buffer zone. Each time a part enters,
limit_switch_3 is enabled and counter_2 increments by 1. Each time a part
leaves, limit_switch_4 is enabled and counter_2 decrements by 1. If there are
100 parts in the buffer zone (counter_2.dn is true), conveyor_A turns on and
stops the conveyor from bringing in any more parts until the buffer has room
for more parts.

See also

Index Through Arrays on page 898

Counter Instructions on page 93

This information applies to the CompactLogix 5370, ControlLogix 5570,

Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380,
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix
5580 controllers.

Publication 1756-RM003V-EN-P - November 2020 99

The CTU instruction counts upward each time the rung-condition-in
transitions from false to true.

Chapter 3 Timer and Counter Instructions

IMPORTANT

• Except when specified, structure operands are shared by multiple instructions.

Operand

Data Type

Format

Description

Accum

DINT

immediate

Value of Counter.ACC.

Mnemonic

Data Type

Description

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

This instruction is not available in structured text.

Operands

Unexpected operation may occur if:

• Output tag operands are overwritten.

• Members of a structure operand are overwritten.

Ladder Diagram

Counter COUNTER tag Counter structure
Preset DINT immediate Value of Counter.PRE.

COUNTER Structure

.CU BOOL The count up enable contains rung-condition-in when

.DN BOOL The done bit when set indicates the counting

.OV BOOL The overflow bit when set indicates the counter

.UN BOOL The underflow when set indicates the counter

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the instruction was last executed.

operation is complete.

incremented past the upper limit of 2,147,483,647.

decremented past the lower limit of -2,147,483,648.