新浪博客

S-Function实现simulink仿真与Vc通信

2012-12-22 13:38阅读：

http://blog.sina.cn/dpool/blog/u/1870921140

S-Function实现simulink仿真与Vc通信


背景：在使用simulink仿真和其他语言编写的仿真模块合作时，总存在两种语言模块的数据交互的问题，本文考虑使用S-Function构建一个单独的通信模块，将该模块添加到simulink模型中，实现仿真数据的交互。
Matlab的simulink仿真有提供一个用户自定义模块，该模块可以用多种编程语言来实现，本文介绍：使用C++的Socket通信来编写代码，实现和Vc的交互。
下面介绍VC++用户自定义模块的实现方法
1、在模型中添加用户自定义模块
该模块位于Simulink、User-Define Function下的S-Function模块
2、添加模块对应的函数名，双击模块，在弹出窗口S-function name
后面输入要定义的函数名，
3、编写模块对应的函数代码，函数代码要求有固定的格式，如下(可以参考simulink的demo中的代码)：(限于篇幅，只贴部分关键代码，完整源代码请看后续链接中的UseFunc.cpp和UseFunc.h)

// Function: mdlStart =======================================================
// Abstract:
// This function is called once at start of model execution. If you
// have states that should be initialized once, this is the place
// to do it.
#define MDL_START
static void mdlStart(SimStruct *S)
{
// Store new C++ object in the pointers vector
 DoubleAdder *da = new DoubleAdder();
ssGetPWork(S)[0] = da;
UseFun_StartSock(S);
}
// Function: mdlOutputs =======================================================
// Abstract:
// In this function, you compute the outputs of your S-function
// block.
static void mdlOutputs(SimStruct *S, int_T tid)
{
// Retrieve C++ object from the pointers vector
 DoubleAdder *da = static_cast<</FONT>DoubleAdder *>(ssGetPWork(S)[0]);

 // Get data addresses of I/O
 InputRealPtrsType u = ssGetInputPortRealSignalPtrs(S,0);
real_T *y = ssGetOutputPortRealSignal(S, 0);
 int InputNum = ssGetInputPortWidth(S, 0);
for(int i=0;i<</FONT>InputNum;i++)
{
y[i] = *u[i];
}
UseFun_SentData(S, y, InputNum);
}
// Function: mdlTerminate =====================================================
// Abstract:
// In this function, you should perform any actions that are necessary
// at the termination of a simulation. For example, if memory was
// allocated in mdlStart, this is the place to free it.
static void mdlTerminate(SimStruct *S)
{
// Retrieve and destroy C++ object
 DoubleAdder *da = static_cast<</FONT>DoubleAdder *>(ssGetPWork(S)[0]);
delete da;
UseFun_CloseSock(S);
}
void UseFun_StartSock(SimStruct *S)
{
int iResult;
WSADATA wsaData;
SOCKET *pSendSocket = new SOCKET;
*pSendSocket = INVALID_SOCKET;
sockaddr_in *pRecvAddr = new sockaddr_in;
unsigned short Port = 27015;

printf('Start socket communication, please wait...');
//----------------------
 // Initialize Winsock
 iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (iResult != NO_ERROR) {
printf('WSAStartup failed with error: %d', iResult);
return ;
}
//---------------------------------------------
 // Create a socket for sending data
 *pSendSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (*pSendSocket == INVALID_SOCKET) {
printf('socket failed with error: %ld', WSAGetLastError());
WSACleanup();
return ;
}
//---------------------------------------------
 // Set up the RecvAddr structure with the IP address of
 // the receiver (in this example case '192.168.1.1')
 // and the specified port number.
 pRecvAddr->sin_family = AF_INET;
pRecvAddr->sin_port = htons(Port);
pRecvAddr->sin_addr.s_addr = inet_addr('127.0.0.1');
ssGetPWork(S)[1] = pSendSocket;
ssGetPWork(S)[2] = pRecvAddr;
}
void UseFun_SentData(SimStruct *S, const real_T *data, int DataNum)
{
int iResult;
char SendBuf[1024]={'\0'};
int BufLen = 1024;
SOCKET *pSendSocket = static_cast<</FONT>SOCKET *>(ssGetPWork(S)[1]);
sockaddr_in *pRecvAddr = static_cast<</FONT>sockaddr_in *>(ssGetPWork(S)[2]);
if (*pSendSocket == SOCKET_ERROR) {
printf('SOCKET_ERROR error: %d', WSAGetLastError());
closesocket(*pSendSocket);
WSACleanup();
return ;
}
//---------------------------------------------
 // Send a datagram to the receiver
 //printf('Sending a datagram to the receiver...');
 int ValidateBufLen = 0;
 for(int i=0;i<</FONT>DataNum;i++)
{
ValidateBufLen = strlen(SendBuf);
sprintf(SendBuf+ValidateBufLen, '%g;', data[i]);
}
iResult = sendto(*pSendSocket,
SendBuf, BufLen, 0, (SOCKADDR *)pRecvAddr, sizeof(sockaddr_in));
}
void UseFun_CloseSock(SimStruct *S)
{
SOCKET *pSendSocket = static_cast<</FONT>SOCKET *>(ssGetPWork(S)[1]);
sockaddr_in *pRecvAddr = static_cast<</FONT>sockaddr_in *>(ssGetPWork(S)[2]);
//---------------------------------------------
 // When the application is finished sending, close the socket.
 printf('Finished socket communication, Closing socket.');
if (closesocket(*pSendSocket) == SOCKET_ERROR)
{
printf('closesocket failed with error: %d', WSAGetLastError());
}
//---------------------------------------------
 // Clean up and quit.
 WSACleanup();
delete pSendSocket;
pSendSocket = NULL;
delete pRecvAddr;
pRecvAddr = NULL;
}
（示例程序实现将输入直接输出，并将输入数据通过socket采用UDP协议将数据发送到网络上）
4、编译C++代码，在matlab中编译，需要先通过matlab命令行设置matlab的mex编译器，方法如下:
S-Function实现simulink仿真与Vc通信
选择VS2005编译器，然后使用mex 命令来编译代码，命令格式：mex cppfile（模块对应的代码的文件名），编译成功会有相应的提示
5、编译成功会产生一个后缀为mexw32的mex程序，有了这个程序，用户自定义模块就可以工作了


附：

Demo说明：两个正弦输入信号经过mux模块集束成一个输入数组，经过自定义模块，最后到达Scope模块显示。在自定义模块(UseFunc)中，通过Socket采用UDP将输入数据发送到某个端口。
1、simulink模型图示（模型文件请看后续链接中的DemoTest.mdl)
S-Function实现simulink仿真与Vc通信

2、运行效果图：
S-Function实现simulink仿真与Vc通信
3、通过辅助程序，收到上面自定义模型发出来的数据如下
S-Function实现simulink仿真与Vc通信
说明:分号前为第一个正弦输入信号的数据，分号后为第二个正弦输入信号的数据

接收端程序代码：（完整源代码请看后续链接中的SocketServer.cpp)
int _tmain(int argc, _TCHAR* argv[])
{
int iResult = 0;
WSADATA wsaData;
SOCKET RecvSocket;
sockaddr_in RecvAddr;
unsigned short Port = 27015;
char RecvBuf[1024];
int BufLen = 1024;
sockaddr_in SenderAddr;
int SenderAddrSize = sizeof (SenderAddr);
//-----------------------------------------------
 // Initialize Winsock
 iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
if (iResult != NO_ERROR) {
wprintf(L'WSAStartup failed with error %d', iResult);
return 1;
}
//-----------------------------------------------
 // Create a receiver socket to receive datagrams
 RecvSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (RecvSocket == INVALID_SOCKET) {
wprintf(L'socket failed with error %d', WSAGetLastError());
return 1;
}
//-----------------------------------------------
 // Bind the socket to any address and the specified port.
 RecvAddr.sin_family = AF_INET;
RecvAddr.sin_port = htons(Port);
RecvAddr.sin_addr.s_addr = htonl(INADDR_ANY);
iResult = bind(RecvSocket, (SOCKADDR *) & RecvAddr, sizeof (RecvAddr));
if (iResult != 0) {
wprintf(L'bind failed with error %d', WSAGetLastError());
return 1;
}
//-----------------------------------------------
 // Call the recvfrom function to receive datagrams
 // on the bound socket.
 wprintf(L'Receiving datagrams...');
iResult = 0;
int RecvNum = 0;
while(RecvNum <</FONT> 100)
{
memset(RecvBuf,0,BufLen);
iResult = recvfrom(RecvSocket,
RecvBuf, BufLen, 0, (SOCKADDR *) & SenderAddr, &SenderAddrSize);
if (iResult == SOCKET_ERROR)
{
wprintf(L'recvfrom failed with error %d', WSAGetLastError());
break;
}
printf('recv dada: %s ', RecvBuf);
RecvNum++;
}
//-----------------------------------------------
 // Close the socket when finished receiving datagrams
 wprintf(L'Finished receiving. Closing socket.');
iResult = closesocket(RecvSocket);
if (iResult == SOCKET_ERROR) {
wprintf(L'closesocket failed with error %d', WSAGetLastError());
return 1;
}
//-----------------------------------------------
 // Clean up and exit.
 wprintf(L'Exiting.');
WSACleanup();
return 0;
}


完整源代码参见：S-Function实现simulink仿真与Vc通信的源代码

我的更多文章

下载客户端阅读体验更佳

APP专享