using C code for serial port communication in matlab via mex file

Question

Ahmet Tuna 2017-5-26

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/342045-using-c-code-for-serial-port-communication-in-matlab-via-mex-file

编辑： Walter Roberson 2017-5-26

Hi,

I have implemented a C code for the serial port Communication. I want to use this function in matlab. I read the documentation about mex file (mex function) and i made the changes which i need for mexFunction. When i write mex serial_port.c to the command line everything is fine and matlab generates serial_port.mexa64. But when i want to use it and write serial_port() to the command line the serial port is not opening. what could be the problem?

here is my code:

#include "mex.h"
#include <stdio.h>
#include <fcntl.h>  
#include <termios.h>
#include <errno.h>  
    void mexFunction (int nlhs, mxArray *plhs[], int nrhs, 
      const mxArray *prhs[])
    {
        if(nrhs != 0) {
        mexErrMsgIdAndTxt("MyToolbox:arrayProduct:nrhs",
                          "zero inputs required.");
        }
        if(nlhs != 0) {
        mexErrMsgIdAndTxt("MyToolbox:arrayProduct:nlhs",
                          "Two output required.");
         }
      char serial;
      struct termios SerialPortSettings;
      serial= open("/dev/ttyACM1", O_RDWR | O_NOCTTY);
      printf("%i \n",serial);
      tcgetattr(serial, &SerialPortSettings);
      cfsetispeed(&SerialPortSettings,B9600);  
      cfsetospeed(&SerialPortSettings,B9600);
      SerialPortSettings.c_cflag &= ~PARENB;
      SerialPortSettings.c_cflag &= ~CSTOPB;
      SerialPortSettings.c_cflag &= ~CSIZE;  
      SerialPortSettings.c_cflag &= ~CS8;
      SerialPortSettings.c_cflag &= ~CRTSCTS;
      SerialPortSettings.c_cflag |= CREAD | CLOCAL ;
      
      SerialPortSettings.c_cc[VMIN] = 9;  
      SerialPortSettings.c_cc[VTIME] = 0; 
      
      SerialPortSettings.c_iflag &= ~(IXON | IXOFF | IXANY);
      SerialPortSettings.c_iflag &= ~(ICANON | ECHO | ECHOE | ISIG);
      
      tcsetattr(serial,TCSANOW,&SerialPortSettings);
      char writeb[9];
      writeb[0]=1;
      writeb[1]=2;
      writeb[2]=0;
      writeb[3]=0;
      writeb[4]=0;
      writeb[5]=0;
      writeb[6]=0;
      writeb[7]=200;
      writeb[8]=writeb[0]+writeb[1]+writeb[2]+writeb[3]+writeb[4]+writeb[5]+writeb[6]+writeb[7];
      
      int bytes_written=0;
      bytes_written=write(serial,writeb,sizeof(writeb));
      char readb[9];
      int bytes_read;
      int a;
      bytes_read=read(serial,&readb,9);
      a=readb[2];
      printf("%i \n",a);
      close(serial);
    }