Hi I have written the followinng serial port program. It compiles without errors. During execution the program does not recieve all the characters that I send from another computer thru minicom. Most of the characters are lost only a few are recieved. The baud rates on both sides are same. Is there something missing in the code ? Please help.
Code:#include <termios.h> #include <stdio.h> #include <fcntl.h> #include <sys/signal.h> #include <sys/types.h> #include <sys/select.h> #include <unistd.h> #include <string.h> #define DEVICE "/dev/ttyS0" int main(void) { int fd; struct termios oldtio, newtio; //open the serial communication device. fd = open(DEVICE, O_RDWR | O_NOCTTY | O_SYNC | O_NONBLOCK); if(fd < 0) { printf("Failed to open device.\n"); return -1; } memset(&newtio, 0, sizeof(newtio)); /* Store the old configuration. This will be restored when we close the library. */ tcgetattr(fd, &oldtio); newtio.c_cflag = B115200 /* Baudrate specified by the user */ \ | CS8 /* character size mask */ \ | CLOCAL /* Ignore modem control lines */ \ | CREAD /* Enable reciever */ \ | CSTOPB; printf("ISIG : %x\n", ISIG); printf("ICANON : %x\n", ICANON); newtio.c_iflag = IGNPAR | ICRNL ; newtio.c_oflag = 0; newtio.c_lflag = ISIG; newtio.c_cc[VMIN]=1; newtio.c_cc[VTIME]=0; printf("newtio.c_lflag: %x\n", newtio.c_lflag); /* Set the new configuration */ tcflush(fd, TCIFLUSH); if(tcsetattr(fd, TCSANOW, &(newtio)) < 0 ) { printf("Failed to set new configuration. Possibly an invalid configuration.\n"); close(fd); return -2; } { char a=0; char b[11]; while(1) { fd_set fds; FD_ZERO(&fds); FD_SET(fd, &fds); select(fd+1, &fds, NULL, NULL, NULL); printf("Select returned.\n"); if(read( fd, &(b[0]), sizeof(char) )< 0) { // perror("reading error."); continue; } // printf("%c",b[0]); putchar(b[0]); } } return 0; }
