/*
  Auslesedemo unter Verwendung von vc920_960.h/.c
  für Voltcraft VC920 & VC960

  www:    http://hardtest.florian-strunk.de
 
*/

#include <stdlib.h>
#include <stdio.h>
#include <string.h> /*kann weg? */
#include <sys/stat.h>
#include <unistd.h>
#include <sys/time.h>
#include <signal.h>
#include <termios.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <fcntl.h> 

#include "vc920_960.h"

#define STD_FLG (0 | CS8 | CREAD & ~PARENB & ~CSTOPB | HUPCL)

int fd;

unsigned int get_time()
{
	struct  timeval ti;
	struct timezone tzp;
        gettimeofday(&ti,&tzp);
	return ti.tv_usec+1000000*ti.tv_sec;
}
                
/*---------------------------------------------------------------------*/
 int open_serial(char* out_dev, int baudrate)
{
        int fd;
	int bdflag;
        struct termios tty;
	int x;
	char device[]="/dev/ttyUSB0";
	
	fprintf(stderr,"Using serial output to %s, baudrate %i\n",
		device,baudrate);

	if (baudrate==19200)
		bdflag=B19200;
	else if (baudrate==9600)
		bdflag=B9600;
	else if (baudrate==4800)
		bdflag=B4800;
	else if (baudrate==2400)
		bdflag=B2400;
	else if (baudrate==1200)
		bdflag=B1200;
	else if (baudrate==38400)
		bdflag=B38400;
	else if (baudrate==57600)
		bdflag=B57600;
	else if (baudrate==115200)
		bdflag=B115200;
	else if (baudrate==230400)
		bdflag=B230400;
	else
	{
		fprintf(stderr,"Unsupported baudrate %i\n",baudrate);
		exit(-1);
	}
		
        fd=open(out_dev,O_RDWR); // ttyS1 = COM2
        if (fd==-1)
        {
                perror("open failed");
                exit(-1);
        }
        tcgetattr(fd, &tty);
        tty.c_iflag = IGNBRK | IGNPAR;
        tty.c_oflag = 0;
        tty.c_lflag = 0;
        tty.c_line = 0;
        tty.c_cc[VTIME] = 0;
        tty.c_cc[VMIN] = 1;
        tty.c_cflag =STD_FLG;
        cfsetispeed(&tty,bdflag);      
        cfsetospeed(&tty,bdflag);      
        tcsetattr(fd, TCSAFLUSH, &tty); 

	return fd;    
}
/*---------------------------------------------------------------------*/
void close_serial(int fd)
{
	close(fd);
}
/*---------------------------------------------------------------------*/ 
void set_rts_dtr(int fd)
{
	int arg;
	arg=TIOCM_RTS|TIOCM_DTR;
	ioctl(fd,TIOCMBIS,&arg);

	arg=TIOCM_RTS;
	ioctl(fd,TIOCMBIC,&arg);
}

/*---------------------------------------------------------------------*/ 
int main(int argc,char **argv)
{
	unsigned char data;
	unsigned char buffer[100];
	char units[20];
	int n;
        int divisor;
	float it;
	unsigned int t,tf;
	char s[10];

        struct dvm_data	dvmdata;

	fd=open_serial("/dev/ttyUSB0", 2400);

	set_rts_dtr(fd); // DTR/RTS setzen

	t=get_time(NULL);
	while(1)
	{
		n=0;
		memset(buffer,0,20);
		while(1)
		{
			read(fd,&buffer[n],1);		
			//if ((buffer[n]&0xf0)==0xe0 || (n==11))
			//	break;

                        if (((n>0) && (buffer[n-1]==0x0D) && (buffer[n]==0x8A)) || (n==11) )
			break;	
			n++;
		}


#if 0
		// Raw output
		for(n=0;n<11;n++)
			printf("%02x ",buffer[n]);
#endif

		tf=(int)((get_time(NULL)-t)/100000.0);
		
		set_dvm_data(buffer, &dvmdata);	

                if (dvmdata.overload==0)
                {

                //int nachkomma = 0;
                //nachkomma = dvmdata.divisor / 10;
                printf("%0.1f %s%0.4f %s%s\n",tf/10.0,dvmdata.sign,dvmdata.digits/dvmdata.divisor,dvmdata.prefix,dvmdata.unit);
                }

                else
                {

                printf("%0.1f %s %s%s\n",tf/10.0,"  .OL ",dvmdata.prefix,dvmdata.unit);
                }
		fflush(stdout);
                
	}
}