Tip #24: MBD Toolbox -Integrate Custom C-code with existing Simulink Models
Often we are getting questions about how to mix existing C-code for various functionalities with existing Simulink Models. There are multiple ways of adding/calling your C-functions from Simulink.
Please check this article How to use your own C code in our Toolbox (Battery Management System example) to learn about how to do it.
Tip #22: MBD Toolbox - How to migrate a Simulink model to a newer toolbox version to avoid "Unresolved Link" message
Sometimes, our team is forced to make changes that will break the Simulink library backward compatibility. In this case, models created with previous versions of a toolbox cannot be opened in a newer version due to "Unresolved Link" error message.
In such cases you will see something like this. The model has been created with MBDT S32K 3.0.0 and imported in MBDT 2018.R1
How to fix it easily?
Use right click on each Simulink block and select Block Parameters (Reference) menu option
The following windows will appear that will help you to identify the broken link:
Edit the Source Block to point to the correct Simulink Library block location. In this case just remove the "/S32K14x" and click Apply
The Simulink Model will be updated and the block will become visible
Tip #20: MBD Toolbox - How to control Symbolics
One of the nice features of Model-Based Design approach is the possibility to generate automatically parts of the Simulink models and reuse/import that code wherever you need.
Here is a code snippet that looks awful IMHO due to:
- differences in function calls compared to actual Simulink Subsystem
- variables prefixes
- bad indentation
MATLAB offers an easy way to customize the global coding styles. Instead of going over the models and modify each subsystem properties you can instruct the code generation about different rules by changing: Identifier Format Control
Tweaking these arguments produces a legible code:
What's you preference ?
Tip #19: MBD Toolbox - How to generate meaningful names for variables in Code Generation
Have you ever wanted to scope or record a variable with FreeMASTER or simply wanted to read the MATLAB generated code but found no meaningful symbol names in C-source or ELF ?
By default, MATLAB/Simulink code generation is going to optimize the program and most of the time the variables might be optimized out or simply defined as locals.
Here is a Simulink model and the associated code generation snippet:
/* S-Function (GMCLIB_SvmStd_SF_FLT): '<S9>/GMCLIB_SvmStd_SF' */
{
SWLIBS_3Syst_FLT Out;
SWLIBS_2Syst_FLT In;
In.fltArg1 = rtb_GMCLIB_ParkInv_SF_o1;
In.fltArg2 = rtb_GMCLIB_ParkInv_SF_o2;
rtb_GMCLIB_SvmStd_SF_o4 = GMCLIB_SvmStd_FLT(&Out, &In);
rtb_GMCLIB_SvmStd_SF_o1 = Out.fltArg1;
rtb_GMCLIB_SvmStd_SF_o2 = Out.fltArg2;
rtb_GMCLIB_SvmStd_SF_o3 = Out.fltArg3;
}In this case, the inputs and outputs are local variables and can't be visible to FreeMASTER therefore you cannot plot them in real time nor reading/understanding the code faster.
void PWM_control_S32K_step(void)
{
/* local block i/o variables */
real32_T rtb_GMCLIB_SvmStd_SF_o1;
real32_T rtb_GMCLIB_SvmStd_SF_o2;
real32_T rtb_GMCLIB_SvmStd_SF_o3;
real32_T rtb_GMCLIB_ParkInv_SF_o1;
real32_T rtb_GMCLIB_ParkInv_SF_o2;
uint32_T rtb_GMCLIB_SvmStd_SF_o4;
Wouldn't be nice to have the symbols like U_ALPHA, U_BETA, PWM_A, PWM_B, PWM_C and SECTOR instead of generic Simulink naming convention ?
Good news! that is possible with a single click.
Just right click on the signal, select Signal Properties and then enable "Test Point"
Do this for all the signals you wish to visualize in FreeMASTER and Simulink is going to highlight all these signal and use them during code generation
Now the generated code should look like this.
/* S-Function (GMCLIB_SvmStd_SF_FLT): '<S9>/GMCLIB_SvmStd_SF' */
{
SWLIBS_3Syst_FLT Out;
SWLIBS_2Syst_FLT In;
In.fltArg1 = PWM_control_S32K_B.U_ALPHA;
In.fltArg2 = PWM_control_S32K_B.U_BETA;
PWM_control_S32K_B.SECTOR = GMCLIB_SvmStd_FLT(&Out, &In);
PWM_control_S32K_B.PWM_A = Out.fltArg1;
PWM_control_S32K_B.PWM_B = Out.fltArg2;
PWM_control_S32K_B.PWM_C = Out.fltArg3;
}Now, it is easier to read the code and the even more important the Simulink is going to generate a global structure that could be easily visualized in FreeMASTER in real-time.
/* Block signals (auto storage) */
typedef struct {
real32_T U_ALPHA; /* '<S8>/GMCLIB_ParkInv_SF' */
real32_T U_BETA; /* '<S8>/GMCLIB_ParkInv_SF' */
real32_T PWM_A; /* '<S9>/GMCLIB_SvmStd_SF' */
real32_T PWM_B; /* '<S9>/GMCLIB_SvmStd_SF' */
real32_T PWM_C; /* '<S9>/GMCLIB_SvmStd_SF' */
uint32_T SECTOR; /* '<S9>/GMCLIB_SvmStd_SF' */
} B_PWM_control_S32K_T;
Hi Daniel,
I have some problems and need your help,I use the 'Automotive Math and Motor Control Library' for MPC5744P in Simulink to control PMSM,and I want to use the 'GMCLIB_SvmStd_FLT' module,and I finished the compile in Simulink and then debuged in Freemaster,but I found the code could not run,then I delete this module to have a text,I found the code could run,so I think this module is the core problem.I also used the 'GMCLIB_SvmStd_F32' module,and everything is OK,but I want to use 'GMCLIB_SvmStd_FLT' module because it accord with my demand.So please help me to find the reason.
Thank you.
Yuyuan Wang.
Tip #18: MBD Toolbox - How to use custom Linker Command Files
Did you know you can use your own custom Linker Command Files (*.lcf/*.ld) to control the code and data section placement in the microprocessor FLASH or RAM physical memories ?
By default the MBD Toolbox is deliver with default memory allocation scripts that are located under ../mbdtbx_xxx/src/... folder (e.g.: ..\mbdtbx_MPC574xP\mbdtbx_pnt\src\s32ds_specific_files in case of MPC5744P)
Any linker file that you create in this folder is loaded (one the MATLAB is restarted) into the Model Configuration Parameters and can be selected by the user to link the generated code according with the rules exposed in the file.
Disable the Default Target Memory Definition and you will get access to the User Defined Target Memory Definition option where you can select your custom file.
This might be useful in case you what to define your own memory arrangement to fit with existing applications or if you want to reuse the generated code with existing IDE based projects.
Hi Daniel,
I am using S32k144 evb board and MATLAB 2019a version. I have installed NXP tool and I am using it.
I am working on eeporm flash code for s32k148 so I want to replace default linker file with my custom file.
I searched in Toolboxes\NXP_MBDToolbox_S32K1xx\mbdtbx_s32k and in \ src folder but there is no such fie default linker file, where I can place my custom linker file or its path.
There is no Default Target Memory Definition option in Model configuration option. There is no User Defined Target Memory Definition option where I can select my custom file.
Will you please help with s32k148evb board and Matlab2019a version , for use your own custom Linker Command Files
Hello sagar.salunkhe@faurecia.com,
Please go to S32K\src\mbdtbx_s32k14x\src\linker\gcc (if you use GCC) and add the linker file you need here. rename it as S32K148_[memory_size]_flash_[custom_name]. The toolbox will show it in the Build Toolchain tab of the config block if you uncheck the Default Target Memory Definitions. If it fails to show it here, please replace the linker file with the one that you need to use.
Marius
Hi Marius,
I tried this solution, but it worked for first time only. After saving setting when I closed the model and opened again it is showing bellow error.
I tried multiple times by closing MATLAB and opening it again ,I found that it is not working always. There is no customized User Defined Target Memory Definitions in drop down window.
My customize files are bellow
Please suggest the right way to do it.
Tip #15: MBD Toolbox - Automotive Math and Motor Control Library supported features
Did you know that using the NXP AMMC Library in conjunction with NXP MBD Toolbox you can design and implement your entire application using just Simulink blocks in a fraction of the time compared other SW development approaches.
No hand-written code is required.
Here is an example of that could be achieved in case of FOC for PMSM.
Tip #14: MBD Toolbox - Simulink Missing Toolbox Library
Have you tried to use a toolbox that you have installed but is does not seems to be present in the Simulink Library ?
Sometimes the Simulink might not update the information correctly. With a simple F5 you can force a library refresh. If something is broken the Simulik will inform about that:
Just click on Fix and select the "Generate Repositories in Memory"
That should do the trick and made all installed toolboxes available in the Simulink Library.
Tip #13: MBD Toolbox - Common license error codes
Have you tried to use the Model Based Design Toolbox but you end-up having a Licensing Error like this ?
Most of the times you can fix this by yourself. The NXP MBD Toolbox is using FlexLM license manager from Flexera Software.
FlexLM error codes with description and possible causes can be found here: FLEXlm Error Codes
The most common source of errors for Model Based Design are:
Error Code | Description |
|---|---|
-1 | Cannot find license file. |
-2 | Invalid license file syntax. |
-5 | No such feature exists. |
-8 | Invalid (inconsistent) license key or signature. The license key/signature and data for the feature do not match. This usually happens when a license file has been altered. |
-9 | Invalid host. The hostid of this system does not match the hostid specified in the license file. |
-10 | Feature has expired. |
-11 | Invalid date format in license file. |
-18 | License server does not support this feature. |
-21 | License file does not support this version. |
-30 | Cannot read license file. |
-31 | Feature start date is in the future. |
-54 | No FEATURESET line in license file. |
-55 | Incorrect FEATURESET line in license file. |
Tip #12: MBD Toolbox - Using multiple toolboxes in the same Matlab instance
Even if multiple installations and instantiations of the NXP MBD Toolbox within a single Matlab release is supported there might be situations when you might want to keep only one active and visible toolbox library in Simulink.
You can do that very easy by resetting the Matlab Search Path to Defaults and then load only the Toolbox you are interested in.
