Ladder Diagram Import, Modeling, Simulation, and Code Generation

Ladder diagram blocks and functions

Ladder Diagram is a graphical programming language used to develop software for programmable logic controllers (PLCs). It is one of the languages that the IEC 61131 Standard specifies for use with PLCs. A program in Ladder Diagram notation is a circuit diagram that emulates circuits of relay logic hardware. The underlying program uses Boolean expressions that translate readily to switches and relays.

The ladder import feature of Simulink^® PLC Coder™ allows you to import Ladder Diagram created with Rockwell Automation^® IDEs such as RSLogix™ 5000 and Studio 5000 into the Simulink environment as a model. The ladder modelling feature of Simulink PLC Coder allows you to create Ladder Diagrams in the Simulink environment as a model.

After importing or creating the Ladder Diagram models, you can do the following from Simulink.

You can edit the imported Ladder Diagram model from within Simulink by using the plcladderlib library.
You can simulate the Ladder Diagram after importing the Ladder diagram into Simulink
You can generate C code from the imported Ladder Diagram and integrate the code into your existing C language-based simulation environments.
You can generate Ladder Diagram code from the imported Ladder Diagram and integrate the code into your Rockwell Automation IDE.
Note
You cannot generate Structured Text code from the Ladder Diagram blocks. The Ladder feature supports only ladder code generation.
You can generate PLC testbench code for the imported Ladder Diagram and verify the code in your Rockwell Automation IDE.

Apps

Simulink PLC Coder

Generate structured text and ladder diagram code from Simulink models, Stateflow charts, and MATLAB functions

Functions

`plcimportladder`	Import ladder diagram into a Simulink subsystem
`plcgeneraterunnertb`	Generate L5X test bench code for specified AOI Runner block and AOI name
`plcgeneratecode`	Generate Structured Text or Ladder Diagram (L5X) for the atomic subsystem
`plcladderlib`	Open the Simulink PLC Coder Ladder Library
`plcladderoption`	Get or set parameter values associated with Ladder Diagram models
`plcloadtypes`	Load the data types for Simulink PLC Coder ladder models
`plccleartypes`	Clear the data types associated with the Simulink PLC Coder ladder models from the workspace
`plcladderinstructions`	Lists ladder instructions identified by Simulink PLC Coder

Blocks

expand all

Basic Building Blocks

XIC	Examine If Closed
XIO	Examine If Open
OTE	Output Energize
OTL	Output Latch
OTU	Output Unlatch

Timers and Counters

TON	Timer On Delay
TOF	Timer Off Delay
RTO	Retentive Timer On
CTU	Count Up
CTD	Count Down
RES	Reset

Program Control

JMP	Jump
LBL	Label
TND	Temporary End
AFI	Always False
NOP	No Operation
MCR	Master Control Reset

Math Operations

ADD	Add inputs
SUB	Subtract inputs
MUL	Multiply inputs
DIV	Divide one input by another
CPT	Evaluate expression

Boolean Operations

AND	Bitwise AND
OR	Bitwise OR
NOT	Bitwise NOT

Bit Operations

ONS	One Shot
OSR	One Shot Rising
OSF	One Shot Falling

Comparison

NEQ	Not Equal To
EQU	Equal To
LEQ	Less Than or Equal To
GEQ	Greater Than or Equal To
LES	Less Than
GRT	Greater than

Move

MOV	Move
CLR	Clear

Organizational Units

AOI Runner	AOI Runner
PLC Controller Suite	PLC Controller
PLC Controller	PLC Controller
Task	Task
Ladder Diagram Program	Ladder Diagram Program
Ladder Diagram Subroutine	Ladder Diagram Subroutine
Ladder Diagram Function Block (AOI)	Ladder Diagram Function Block (AOI)

Input/Output

Variable Read	Variable Read
Variable Write	Variable Write

Miscellaneous

COP	Copy File
FLL	File Fill
Junction	Junction

Reference Blocks

Power Rail Start	Power Rail Start
Power Rail Terminal	Power Rail Terminal
Rung Terminal	Rung Terminal

Custom PLC Instruction

Custom Instruction

Create custom ladder instruction

Topics

Supported Features in Ladder Diagram

Ladder features and elements that are supported by Simulink PLC Coder.

Import L5X Ladder Files into Simulink

Importing ladder files into Simulink.

Modeling and Simulation of Ladder Diagrams in Simulink

Create Ladder Diagrams in Simulink and perform simulation.

Generating Ladder Diagram Code from Simulink

Generate Ladder Diagram code (L5X) from Simulink.

Generating C Code from Simulink Ladder

Generate C code from a Simulink Ladder Diagram Model.

Verify Generated Ladder Diagram Code

Verify generated code against the original Simulink model in your IDE using a generated test bench.

Create Custom Instruction in PLC Ladder Diagram Models

Create user-defined instruction in PLC Ladder Diagram models.

Featured Examples

Tank Control Simulation and Code Generation Using Ladder Logic

Do ladder logic simulation and code generation from ladder tank controller model.

Using Timers in Ladder Logic

Model and simulate a motor controller in Simulink® by using Ladder Logic. The example uses the ladder Timer instruction to implement the logic for delayed switching of a motor. The timer T1 is used to control the starting delay and the timer T2 is used to control the stopping delay.

Open Model

Temperature Control Simulation and Code Generation Using Ladder Logic

Model a temperature controller in Simulink® by using ladder logic. The example also showcases test case generation using Simulink Design Verifier™, C and ladder code generation, and ladder testbench generation.

Documentation