file:///media/jing/55cb2dc9-b78d-4240-b308-f1c582cebe3d/home/jing/setserial-2.17/miniserialdoc.html

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/* found a very useful ubuntu/linux mini serial comm online */
/* I tested the write/read */
/* I just had to changed one line */
/* Author Jing : O_RDWR | O_NOCTTY -> O_RDWR */
/* 9600, 8N1, XON/XOFF
<body>

  fd=open("/dev/ttyUSB0", O_RDWR);
  if (fd<=0)
    printf("error\n");
  else
    printf("ttyS0 opened succesfully\n");
  
  tcgetattr(fd, &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_lflag &= ~(IXON | IXOFF);
  SerialPortSettings.c_lflag &= ~(ICANON | ECHO |ECHOE| ISIG);
  tcsetattr(fd, TCSANOW, &SerialPortSettings);
  int bytes_written =0;
  bytes_written = write(fd, "AAAAAAAAAAAAA\r\n",15);
   
  printf("%d\n", bytes_written);
  if (bytes_written <0)
    printf("write() of 2 bytes failed\n", stderr);
  sleep(1);
    read(fd,ma,10);
    printf("%s\n",ma);
		      close(fd);
  </body>
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