#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>

int main()
{
      
        struct termios tio;
        
     	const char *device = "/dev/ttyS0";
  	
  	char d[50];
	int i=0;
	
	char c[50];
        int h = 0;
	int g=0;
        long b,m = 0;
        long k = 1000000000;
        long j = 1000000000;
	int tty_fd;
  
	//printf("enter the number of characters:");
	//scanf("%d",&n);
        //printf("\n");
	tty_fd = open(device, O_RDWR | O_NOCTTY | O_NDELAY);
	if(tty_fd == -1) {
	  printf("failed to open port\n");
	  return EXIT_FAILURE;
	}

  	memset(&tio,0,sizeof(tio));
        tio.c_iflag=0;
        tio.c_oflag=0;
        tio.c_cflag=CS8|CREAD|CLOCAL;           // 8n1, see termios.h for more information
        tio.c_lflag=0;
        tio.c_cc[VMIN]=1;
        tio.c_cc[VTIME]=0;
 
        
        cfsetospeed(&tio,B115200);            // 115200 baud
        cfsetispeed(&tio,B115200);            // 115200 baud
 	tcflush(tty_fd, TCIFLUSH);
        tcsetattr(tty_fd,TCSANOW,&tio);
  	
	d[50]= '\0';
        c[50]='\0';
  	
		
  	  	  	while( i< 50 )
			{ 
  				scanf("%c",&c[i]);  				
   				//write(tty_fd,&c[i],1);
				//read(tty_fd,d,i); 
  	  	  	  	//printf("%s",d);
				i = i+1 ;
			}
                        
			if (write(tty_fd,c,50)>0)
                        {  printf("sucess.. written!\n\n");
				 for ( i; i<j; i++)
  				{ for ( m; m<k ; m++ );
				}}
        while (h < 50 ){
			read(tty_fd,&d[h],1) ;
   			
   			printf("%c",d[h]);
			h++;
			//else
 			//printf( " you can't see me ok! " );
                        }

            		
  			
  			
  				
				
								
				
			
		
			
                 
}