serial connector1

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <termios.h>
#include <stdio.h>
#include <stdlib.h>
/* baudrate settings are defined in <asm/termbits.h>, which is included by <termios.h> */
#define BAUDRATE B38400
/* change this definition for the correct port */
#define MODEMDEVICE "/dev/ttyUSB0"
#define _POSIX_SOURCE 1 /* POSIX compliant source */
#define FALSE 0
#define MAX 50
#define TRUE 1
volatile int STOP=FALSE;
int
main()
{
        int i, fd, res;
        char line[MAX], c;
        struct termios oldtio,newtio;
        char buf[255];
        /* Open modem device for reading and writing and not as controlling tty because we don't want to get killed if linenoise sends CTRL-C.  */
        fd = open(MODEMDEVICE, O_RDWR | O_NOCTTY );
        if (fd <0) {
                perror(MODEMDEVICE); exit(-1);
        }
        tcgetattr(fd,&oldtio); /* save current serial port settings */
        bzero(&newtio, sizeof(newtio)); /* clear struct for new port settings */
        /* BAUDRATE: Set bps rate. You could also use cfsetispeed and cfsetospeed.  CRTSCTS : output hardware flow control (only used if the cable has
                    all necessary lines. See sect. 7 of Serial-HOWTO) CS8     : 8n1 (8bit,no parity,1 stopbit) CLOCAL  : local connection, no modem contol
"putty_emul.c" 83L, 3563C                                                                                                                            1,1           Top
         newtio.c_cc[VSWTC]    = 0;     /* '\0' */
         newtio.c_cc[VSTART]   = 0;     /* Ctrl-q */
         newtio.c_cc[VSTOP]    = 0;     /* Ctrl-s */
         newtio.c_cc[VSUSP]    = 0;     /* Ctrl-z */
         newtio.c_cc[VEOL]     = 0;     /* '\0' */
         newtio.c_cc[VREPRINT] = 0;     /* Ctrl-r */
         newtio.c_cc[VDISCARD] = 0;     /* Ctrl-u */
         newtio.c_cc[VWERASE]  = 0;     /* Ctrl-w */
         newtio.c_cc[VLNEXT]   = 0;     /* Ctrl-v */
         newtio.c_cc[VEOL2]    = 0;     /* '\0' */

        /* now clean the modem line and activate the settings for the port */
        tcflush(fd, TCIFLUSH);
        tcsetattr(fd,TCSANOW,&newtio);

        /* terminal settings done, now handle input In this example, inputting a 'z' at the beginning of a line will exit the program.  */
        i = 0;
        while ((c = getchar()) && i < MAX - 1) {
                line[i++] = c;
                if (c == '\n')
                        break;
        }
        line[i] = 0;
        write(fd, line, i);
        i = 0;
        while ((c == getchar()) != '\n')
                line[i++] = c;
        line[i] = '\0';
        printf("%s\n", line);
         /* restore the old port settings */
        tcsetattr(fd,TCSANOW,&oldtio);
        return (0);
}