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Creating a Model with CppModel

CppModel is a framework that allows simulating both C++ and C models. It leverages the fact that C++ compilers can compile C code, making the model structure consistent across both languages.

Creating a C++ Model​

To create a C++ model, start by defining a class that extends the CppModel::Model base class. This base class provides abstractions for inputs and outputs.

Example: MyFirstModel​

MyFirstModel.h

#include <cppmodel/Model.h>

class MyFirstModel : public CppModel::Model
{
public:
	void RunCyclic(double stepTime) override;
};

MyFirstModel.cpp

#include "MyFirstModel.h"

void MyFirstModel::RunCyclic(double stepTime)
{
	int in = inputs["input1"].get<int>();
	int out = in * 2;
	outputs["output1"] = out;
}

Simplified C++ Model​

If you prefer a simpler model with precise types and fewer abstractions, you can use a generic class.

MySimplerModel.h

class MySimplerModel
{
public:
	int in;
	int out;

	void RunCyclic(double stepTime);
};

MySimplerModel.cpp

void MySimplerModel::RunCyclic(double stepTime)
{
	out = in * 2;
}

Running the Model​

Both types of C++ models can be executed within a simulation by calling their RunCyclic() method.

Creating a C Model​

For a C model, you can define a simple function to handle the simulation logic.

Example: MyCModel​

MyCModel.h

#ifdef __cplusplus
extern "C" {
#endif

extern int in;
extern int out;
void MyCModel_RunCyclic(double stepTime);

#ifdef __cplusplus
}
#endif

MyCModel.c

#include "MyCModel.h"

void MyCModel_RunCyclic(double stepTime)
{
	out = in * 2;
}

Running the Model​

Similar to the C++ model, the C model can also be executed in a simulation by invoking the MyCModel_RunCyclic() function.

By following these examples, you can create and simulate models in both C++ and C using the CppModel framework.