Generate Custom Code by Using IDE-Specific Callback Functions

Replace strings, add custom headers, print a list of variables, and so on by generating custom code. Customize the code generated for supported target IDEs by creating IDE-specific custom callback functions. The custom callback functions can modify the generated code by using post-code generation callback functions or the intermediate controller cell array structure by using pre-code generation callback functions.

Custom Code Generation Workflow

To generate custom code for your target IDEs by using custom callback functions:

1. Create a custom pre- or post- code generation callback function. Place the callback functions on the MATLAB^® path.

2. Generate custom code by using Simulink^® PLC Coder™.

Create a Custom Callback Function

Create a custom pre-code generation callback function by using this template. Replace the Pre-Code Generation Callback File Name with the name of the pre-code generation callback file for your target IDE from the table. The pre-code generation function operates on the controller structure which contains information such as variable names, data types, and so on.

function controller = Pre-Code Generation Callback File Name(controller)
% add your custom actions here
end

Create a custom post-code generation callback function by using this template. Replace the Post-Code Generation Callback File Name with the name of the post-code generation callback file for the target IDE from the table. The post-code generation function performs operations such as replacing string values, adding a header to every code section, and so on.

function generatedFiles = Post-Code Generation Callback File Name(fileNames)
fileName = fileNames{1};
str = fileread(fileName); % reading the file contents%   do modifications to str here, f.ex.:
%   str = regexprep(str,'BOOL_TO_LREAL','BOOL_TO_INT');
%   str = regexprep(str,'<USINT/>','<INT/>');
%   str = regexprep(str, 'END_STRUCT','END_STRUCT;');
sfprivate ('str2file', str, fileName);
generatedFiles = {fileName};
end

Target IDE Name	Pre-Code Generation Callback File Name	Post-Code Generation Callback File Name
3S-Smart Software Solutions CODESYS Version 2.3	plc_precg_callback_codesys23	plc_postcg_callback_codesys23
3S-Smart Software Solutions CODESYS Version 3.3	plc_precg_callback_codesys33	plc_postcg_callback_codesys33
3S-Smart Software Solutions CODESYS Version 3.5	plc_precg_callback_codesys35	plc_postcg_callback_codesys35
B&R Automation Studio® Version 3.0	plc_precg_callback_brautomation30	plc_postcg_callback_brautomation30
B&R Automation Studio Version 4.0	plc_precg_callback_brautomation40	plc_postcg_callback_brautomation40
Beckhoff® TwinCAT® 2.11	plc_precg_callback_twincat211	plc_postcg_callback_twincat211
Beckhoff TwinCAT 3.0	plc_precg_callback_twincat3	plc_postcg_callback_twincat3
PHOENIX CONTACT Software MULTIPROG® 5.0	plc_precg_callback_multiprog50	plc_postcg_callback_multiprog50
Phoenix Contact® PC WORX™ 6.0	plc_precg_callback_pcworx60	plc_postcg_callback_pcworx60
Rockwell Automation® RSLogix™ 5000	plc_precg_callback_rslogix5000	plc_postcg_callback_rslogix5000
Rockwell Automation Studio 5000	plc_precg_callback_studio5000	plc_postcg_callback_studio5000
Siemens® SIMATIC® STEP® 7	plc_precg_callback_step7	plc_postcg_callback_step7
Siemens TIA Portal	plc_precg_callback_tiaportal	plc_postcg_callback_tiaportal
Siemens TIA Portal: Double Precision	plc_precg_callback_tiaportal_double	plc_postcg_callback_tiaportal_double
Generic	plc_precg_callback_generic	plc_postcg_callback_generic
PLCopen XML	plc_precg_callback_plcopen	plc_postcg_callback_plcopen
Rexroth IndraWorks	plc_precg_callback_indraworks	plc_postcg_callback_indraworks
OMRON® Sysmac® Studio	plc_precg_callback_omron	plc_postcg_callback_omron

Create a custom pre-code generation callback function by using this template. Replace the Pre-Code Generation Callback File Name with the name of the pre-code generation callback function from the table. The pre-code generation function operates on the controller structure which contains information such as variable names, data types, and so on.

function controller = Pre-Code Generation Callback File Name(controller)
% add your custom actions here
end

Create a custom post-code generation callback function by using this template. Replace the Post-Code Generation Callback File Name with the name of the post-code generation callback function from the table. The post-code generation function performs operations such as replacing string values, adding a header to every code section, and so on.

function generatedFiles = Post-Code Generation Callback File Name(fileNames)
fileName = fileNames{1};
str = fileread(fileName); % reading the file contents%   do modifications to str here, f.ex.:
%   str = regexprep(str,'BOOL_TO_LREAL','BOOL_TO_INT');
%   str = regexprep(str,'<USINT/>','<INT/>');
%   str = regexprep(str, 'END_STRUCT','END_STRUCT;');
sfprivate ('str2file', str, fileName);
generatedFiles = {fileName};
end

Generate Custom Code

1. To create a custom pre—code generation callback function file called plc_precg_callback_codesys23.m, copy and paste this code into a MATLAB script and save the file. Place the file on the MATLAB path.

   function controller = plc_precg_callback_codesys23(controller)
   
   fprintf(1, 'processing by plc_postcg_callback_codesys23\n');
   
   end

2. To create a custom post—code generation callback function file called plc_postcg_callback_codesys23.m, copy and paste this code into a MATLAB script and save the file. Place the file on the MATLAB path. This callback function:

   1. Reads the generated code file. For example, plcdemo_simple_subsystem.exp.

   2. Scans the read string and finds the string S1 and replaces it with the string s1.

   3. Writes the modified string back to the generated file.

   function generatedFiles = plc_postcg_callback_codesys23(fileNames)
   fileName = fileNames{1};
   str = fileread(fileName); % reading the file contents%   do modifications to str here, f.ex.:
   %   str = regexprep(str,'BOOL_TO_LREAL','BOOL_TO_INT');
   %   str = regexprep(str, 'END_STRUCT','END_STRUCT;');
   str = regexprep(str,'<S1>','<s1>');
   sfprivate ('str2file', str, fileName);
   generatedFiles = {fileName};
   end  

3. Open and run the Generate Structured Text Code for a Simple Simulink Subsystem.

   openExample('plccoder/GenerateStructuredTextCodeForASimpleSimulinkRSubsystemExample')

4. Open the PLC Coder app, click Settings > PLC Code Generation. Change Target IDE to 3S CoDeSys 2.3. Click OK.

5. Select the SimpleSubsystem block. In the PLC CODE tab, click Generate PLC Code.

Observe the MATLAB command line output, the string processing by plc_postcg_callback_codesys23 is printed during code generation. In the generated code, the string S1 is replaced with the string s1. This image shows the generated custom code with the replaced string.

Related Topics

• Import and Verify Structured Text Code
• Create Custom Target IDE for Code Generation

External Websites

• https://www.mathworks.com/videos/advanced-techniques-for-customizing-iec-61131-code-generation-for-plcs-1607094156796.html