c++ - Programming Linux serial timings -

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im trying write small program gets values through serial port, , presents on screen. ive read several guides this, link.

now got in trouble believe timing, wrote 2 small pieces of code see if narrow problem down.

the code posted here 1 sender , 1 reciever, sender outputs 11:22 , receiever should recieve , present on screen. sort of this, lots of blank lines, , skipped letters. guess im missing fundamental, due lack of knowledge :)

please see code below: note, crude & indention got screwed men trying copy , paste gvim.. :)

receiver:

#include <iostream> #include <string.h> #include <unistd.h> #include <fcntl.h>  #include <errno.h> #include <termios.h> #include <stdio.h>   using namespace std; int main() {  int fd;          //desc serial port.  char in[20];    //char array data serial port    struct termios options;   tcgetattr(fd,&options);  cfsetispeed(&options,b19200); cfsetospeed(&options,b19200);  options.c_cflag |= (clocal | cread);   options.c_cflag &= ~parenb; options.c_cflag &= ~cstopb; options.c_cflag &= ~csize; options.c_cflag |= cs8; //options.c_cc[vmin] = 5;   tcsetattr(fd,tcsanow,&options);  fd = open("/dev/ttys0", o_rdwr | o_noctty | o_ndelay);    if (fd == -1) {     cout << "could not open port." << endl; } else fcntl(fd,f_setfl,0);    while(1){      read (fd, in,sizeof in);   cout << in << endl;    }         }

sender: (same includes above)

    int main()      {      int fd;     struct termios options;       tcgetattr(fd, &options);     cfsetispeed(&options, b19200);     cfsetospeed(&options, b19200);      options.c_cflag |= (clocal | cread);      options.c_cflag &= ~parenb;     options.c_cflag &= ~cstopb;     options.c_cflag &= ~csize;     options.c_cflag |= cs8;     options.c_oflag |=opost;      tcsetattr(fd,tcsanow, &options);      fd = open("/dev/ttys0",o_rdwr | o_noctty | o_ndelay);      if (fd == -1)        {     cout << "cannot open port" << endl;     }                            else                                 fcntl(fd,f_setfl,0);                            while(1){                                                                    write(fd,"11:22\n",6);                                                                       usleep(1000); //have little break between messages.. prob not neceserry.     }

}


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