Verify Generated Code by Using Cosimulation
Verify your generated code by using cosimulation. The generated code and testbench run on a Codesys software-based programable logic controller (soft PLC). The Simulink ™ model uses Open Platform Communication Unified Architecture (OPC UA) to communicate with and retrieve the cosimulated data from the soft PLC. The Simulink model verifies the generated code by comparing the model simulation results to the cosimulated soft PLC results.
Prerequisites
On your system, you must have installed:
Codesys V3.5.SP16 + IDE or Codesys V3.5 SP16 Patch 1 + IDE
Industrial Communication Toolbox™
Simulink® PLC Coder™
Model Description
The simple_cosim
model is made up of the SimpleSubsystem
block and the MATLAB System (PLCCOSIM)
block. During simulation, the model compares values from the SimpleSubsystem
block to the values from the soft plc which are retrieved by using the MATLAB System (PLCCOSIM)
block.
The SimpleSubsystem
block contains a simple feedback loop.
The MATLAB System
block is set up to run the PLCCOSIM.m
file. The file contains the code to set up OPC UA communications and retrieve the cosimulated data from the soft PLC.
type PLCCOSIM.m
classdef PLCCOSIM < matlab.System % PLCCOSIM Add summary here % % This template includes the minimum set of functions required % to define a System object with discrete state. % Public, tunable properties properties end properties(DiscreteState) CycleNum; end % Pre-computed constants properties(Access = private) UAObj; DeviceNode; Cycle_U; Cycle_Y; TestCycleNum; PreviousCycleNum; end methods(Access = protected) function setupImpl(obj) % Perform one-time calculations, such as computing constants % init opc UA server connection obj.UAObj = opcua('opc.tcp://localhost:4840'); connect(obj.UAObj); obj.DeviceNode = findNodeByName(obj.UAObj.Namespace,'DeviceSet','-once'); obj.Cycle_U = findNodeByName(obj.DeviceNode,'cycle_U'); obj.Cycle_Y = findNodeByName(obj.DeviceNode,'cycle_Y'); obj.TestCycleNum = findNodeByName(obj.DeviceNode,'testCycleNum'); obj.PreviousCycleNum = findNodeByName(obj.DeviceNode,'previousCycleNum'); end function y = stepImpl(obj,u) % Implement algorithm. Calculate y as a function of input u and % discrete states. obj.CycleNum = obj.CycleNum+1; writeValue(obj.UAObj, obj.Cycle_U, u); writeValue(obj.UAObj, obj.TestCycleNum, obj.CycleNum); valueUpdated = false; for rct = 1:100 previousCycleNumValue = readValue(obj.UAObj, obj.PreviousCycleNum); if previousCycleNumValue == obj.CycleNum valueUpdated = true; y = readValue(obj.UAObj, obj.Cycle_Y); break end pause(0.001) end if ~valueUpdated error('not get the value for cycle number %d', obj.CycleNum); end end function resetImpl(obj) % Initialize / reset discrete-state properties obj.CycleNum = 0; writeValue(obj.UAObj, obj.TestCycleNum, obj.CycleNum); writeValue(obj.UAObj, obj.PreviousCycleNum, obj.CycleNum); end function out = getOutputSizeImpl(obj) out = propagatedInputSize(obj,1); end function out = getOutputDataTypeImpl(obj) out = propagatedInputDataType(obj,1); end function c1 = isOutputComplexImpl(obj) c1 = false; end function c1 = isOutputFixedSizeImpl(obj) c1 = true; end function s = getDiscreteStateImpl(obj) s = obj.CycleNum; end end end
Compile, and Simulate the Codesys Project
The Codesys project file runs the generated code on the soft PLC. If you have the Codesys V3.5.SP16 + IDE, use the plc-cosim_v3sp16.project
as the project
file. If you have the Codesys V3.5.SP16 Patch 1+ IDE, use the plc-cosim_v3sp16patch1.project
as the project
file.
In the Windows ® system tray, select CODESYS Control Win SysTray -x64, right-click, and select Start PLC.
Open the project file based on the Codesys Target IDE version.
Double-click
CODESYS_Control_Win_V3_x64
and select Scan Network.In the Scan Network tab, select your device in the Select Device window. Click OK.
Select Build > Build.
6.Select Online > Login.
7. Select Debug > Start.
The soft PLC is now running the generated code.
Simulate the Model and Verify Generated Code
Simulate the Simulink ™ model and verify the generated code by comparing the simulation model results to the soft PLC results.The soft PLC results are retrieved by using the OPC UA connection.
Open the
simple_cosim.slx
file
% open_system('simple_cosim')
2. Simulate the model. Verify the generated code by comparing the model simulation results to the soft PLC cosimulation results.