#define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/signal.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/shm.h>
#include <string.h>
#include <errno.h>
#include <sched.h>
#include <time.h>
#include <pthread.h>
#include <semaphore.h>




#define BAUDRATE B9600
#define MODEMDEVICE "/dev/ttyS0"
#define TRUE 1
#define FALSE 0

//Threads
pthread_t ReadThread; 

//Global Variables
volatile int STOP = FALSE;
char read_buf[13] = "\0";


//file descriptor
int fd_r;

//place for old and new port settings for serial port
struct termios oldtio;


//Called Functions
void portconfig(int *);//serial port configuration settings
void listenport(int );//waiting serial port for input

//Thread Functions//////////////////////////////////////

void *ReadThreadFunc(void *);

///////////////////////////////////////////////////////


main()
{

	int code;

	
	fd_r = open(MODEMDEVICE,O_RDWR | O_NOCTTY | O_NDELAY);
	if(fd_r < 0)
	{
		perror(MODEMDEVICE);
		exit(-1);	
	}

	code = tcgetattr(fd_r,&oldtio); //Save the current port settings
	if(code < 0)
		{
		 perror("Getting attributes failed!");
		 exit(-1);	
		}


	//serial port configuration settings for file descriptor
	portconfig(&fd_r);

	
	//Threads Calling//////////
	if(pthread_create(&ReadThread, NULL, ReadThreadFunc, NULL) != 0)
	{
		perror("Read Thread Creation FAILURE!!!\n");
		return -11;
	}

	

	//Wait Called Threads//////
	pthread_join(ReadThread, NULL);

	

	tcsetattr(fd_r,TCSANOW,&oldtio);	//restore old port settings.
	close(fd_r);
	

	return 0;
}



/* New port settings for canonical input processing */
void portconfig(int *fdf)
{
	struct termios newtio;
	int kod;
	
	newtio.c_cflag = 0; 
	
	newtio.c_iflag = 0 ; 	
	
	newtio.c_oflag = 0;			
	
	newtio.c_lflag = 0;

	kod=tcsetattr(*fdf,TCSANOW,&newtio);	//changes occurs immediately.
	if(kod < 0)
	{
		perror("Setting attributes failed!");
		exit(-1);	
	}

	

	
	newtio.c_cflag = BAUDRATE | CS8  | CREAD | CLOCAL | PARENB | PARODD | CRTSCTS ;
	
	newtio.c_iflag = INPCK; 	
	
	newtio.c_oflag = 0;			
	
	newtio.c_lflag = NOFLSH;

	newtio.c_cc[VMIN] = 13;

	newtio.c_cc[VTIME] = 0;

	tcflush(*fdf,TCIFLUSH);		//flushed data received but not read.
	
	kod=tcsetattr(*fdf,TCSANOW,&newtio);	//changes occurs immediately.
	
	if(kod < 0)
	{
		perror("Setting attributes failed!");
		exit(-1);	
	}
}





void *ReadThreadFunc(void *ptr)
{
	int numbytes = 0, i = 0;
	strcpy(read_buf, "\0");	
	
	while(STOP==FALSE)
	{		
						
		numbytes = read(fd_r, read_buf, 13);
	
		if(numbytes > 0)
		{			
			printf(":%s:%d\n",read_buf,numbytes);
		
		}		
	}


}

#include<stdio.h>
#include<stdlib.h>
#include<fcntl.h>
#include<termios.h>
#include<unistd.h>
#include<string.h>
#include <aio.h>
#include <errno.h>


#define BAUDRATE B9600
#define SERIALDEVICE "/dev/ttyS1"
#define TRUE 1
#define FALSE 0

void portconfig(int *);


main()

{

int fd_w, code;
int n = 13;
int i = 0;

struct termios oldtio;

char data[13] = "13.2 21.3\0";


fd_w = open(SERIALDEVICE,O_RDWR | O_NOCTTY |  O_NDELAY);	//opening serial port device for write action
if(fd_w < 0)
	{
	 perror(SERIALDEVICE);
	 exit(-1);	
	}

code = tcgetattr(fd_w,&oldtio);

if(code < 0)
	{
	 perror("Getting attributes failed!");
	 exit(-1);	
	}

portconfig(&fd_w);



for(i = 0; i < 10; i++)
	{ 
		write(fd_w,data,n);  
		puts(data);
		
	}

tcsetattr(fd_w,TCSANOW,&oldtio);	//restore old port settings.
close(fd_w);


}



/* Port configuration function */
void portconfig(int *device)
{
struct termios newtio;
int cod = 0;


newtio.c_cflag = 0; 
	
newtio.c_iflag = 0 ; 	
	
newtio.c_oflag = 0;			

newtio.c_lflag = 0;

cod=tcsetattr(*device,TCSANOW,&newtio);	
if(cod<0)
	{
	 perror("Setting attributes failed!");
	 exit(-1);	
	}



newtio.c_cflag = BAUDRATE | CS8 | CLOCAL |  PARENB | PARODD | CRTSCTS;

newtio.c_lflag = NOFLSH;

newtio.c_iflag = 0;

newtio.c_oflag = 0;


tcflush(*device,TCOFLUSH);//flushes untransmitted output
cod=tcsetattr(*device,TCSANOW,&newtio);	//changes occurs immediately.

if(cod<0)
	{
	 perror("Setting attributes failed!");
	 exit(-1);	
	}

}