/* ISEG SHQ control Copyright I.Tsurin Liverpool University V1.0 (10.04.2011)    */

/* http://www.iseg-hv.com/start.php/lang.en/start/hardware/prd_showproduct/id.57 */
/* http://slackware.osuosl.org/slackware-3.3/docs/mini/Serial-Port-Programming   */
/* http://www.easysw.com/~mike/serial/serial.html                                */

/* Acknowledgment: http://www.daniweb.com/software-development/c/code/216534     */
/* Acknowledgment: Jens Preiss (Uni Freiburg) for giving this work a momentum    */

#include <stdio.h>   /* Standard input/output definitions    */
#include <string.h>  /* String function definitions          */
#include <unistd.h>  /* UNIX standard function definitions   */
#include <fcntl.h>   /* File control definitions             */
#include <errno.h>   /* Error number definitions             */
#include <termios.h> /* POSIX terminal control definitions   */

#define Wsize 32     /* The longest string has 27 characters */

int fd;

int InitPort(void)
  {
    struct termios options;

//    fd = open("/dev/ttyUSB0", O_RDWR | O_NOCTTY | O_NDELAY);
    fd = open("/dev/ttyS0", O_RDWR | O_NOCTTY | O_NDELAY);

    if (fd == -1)
      {
        fputs("Unable to open port\n", stdout);
        return 0;
      }
    else
      {
        tcgetattr(fd, &options);

        cfsetispeed(&options, B9600);        /* Set the input  baud rate   */
        cfsetospeed(&options, B9600);        /* Set the output baud rate   */

        options.c_cflag |= (CLOCAL | CREAD); /* Enable receiver, set local */

        options.c_cflag &= ~PARENB;          /* Clear parity enable        */
        options.c_cflag &= ~CSTOPB;          /* Remove 2nd stop bit        */
        options.c_cflag &= ~CSIZE;           /* Clear data length          */
        options.c_cflag |= CS8;              /* Character size = 8 bits    */

        options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);  /* RAW input  */
        options.c_oflag &= ~OPOST;                           /* RAW output */

        options.c_cflag &= ~CRTSCTS;      /* Disable hardware flow control */

        tcsetattr(fd, TCSANOW, &options);    /* set attributes immediately */
        return 1;
      }
  }


int WritePort(char Command[])
  {
    char *BufPtr;
    int i;

    BufPtr = Command;

    for (i=0; i<strlen(Command); i++)
      {
        usleep(100);
        write(fd, BufPtr, 1);
        BufPtr++;
      }
    return 1;
  }


int ReadPort(char *wPtr1, char *wPtr2)
  {
    int i;

    i=0;
    while (i<Wsize)
      {
        wPtr1[i]= 0x00;
        wPtr2[i]= 0x00;
	i++;
      }

    i=0;
    while (i<Wsize)
      {
        usleep(100);
        while(read(fd, wPtr1, 1)<0){}
	if ((( wPtr1[-1]=='\r') || ( wPtr1[-1]=='\n')) &&
	    ((*wPtr1    =='\r') || (*wPtr1    =='\n'))) break;
        wPtr1++;
	i++;
      }

    i=0;
    while (i<Wsize)
      {
        usleep(100);
        while(read(fd, wPtr2, 1)<0){}
	if ((( wPtr2[-1]=='\r') || ( wPtr2[-1]=='\n')) &&
	    ((*wPtr2    =='\r') || (*wPtr2    =='\n'))) break;
        wPtr2++;
	i++;
      }
  }

char *sgets(char *line, size_t size)
{
   size_t i;
   for ( i = 0; i < size - 1; ++i )
   {
      int ch = fgetc(stdin);
      if ( ch == '\n' || ch == EOF )
      {
         break;
      }
      line[i] = ch;
   }
   line[i] = '\0';
   return line;
}


int main(void)
{
  const char delimiters[] = " ,;\t";
  unsigned Chan, Volt, Ramp, Vmax, Vlim1, Vlim2;
  int SW1, SW2;
  int i;

  char Word1[Wsize], Word2[Wsize], Buffer[Wsize];
  char AChan[5], AVolt[5], ARamp[5];

  if (!InitPort()) return 0;

/* read U_out_max for the given model number */
  WritePort("#\r\n");
  ReadPort(Word1, Word2);

  for(i=0;i<Wsize;i++) Buffer[i]=0x00;
  strncpy(Buffer, Word2+12, 4);
  Vmax = atoi(Buffer);

/* read voltage limit in Chan 1 */
  WritePort("M1\r\n");
  ReadPort(Word1, Word2);

  for(i=0;i<Wsize;i++) Buffer[i]=0x00;
  strncpy(Buffer, Word2+0, 3);
  Vlim1 = Vmax * atoi(Buffer) / 100;

/* read voltage limit in Chan 2 */
  WritePort("M2\r\n");
  ReadPort(Word1, Word2);

  for(i=0;i<Wsize;i++) Buffer[i]=0x00;
  strncpy(Buffer, Word2+0, 3);
  Vlim2 = Vmax * atoi(Buffer) / 100;


  while(1)
     {

/* read status of switch 1 */
       WritePort("T1\r\n");
       ReadPort(Word1, Word2);

       for(i=0;i<Wsize;i++) Buffer[i]=0x00;
       strncpy(Buffer, Word2+0, 3);
       SW1 = !((atoi(Buffer) & 0x08)>>3);

/* read status of switch 2 */
       WritePort("T2\r\n");
       ReadPort(Word1, Word2);

       for(i=0;i<Wsize;i++) Buffer[i]=0x00;
       strncpy(Buffer, Word2+0, 3);
       SW2 = !((atoi(Buffer) & 0x08)>>3);

/* read input parameters */
       char Text[11] = "";
       char *TPtr, *token;

       fputs("Enter Ch# U(V) Ramp(V/s): ", stdout);
       fflush(stdout);
       sgets(Text, sizeof Text);
       TPtr = Text;

       token = strsep(&TPtr, delimiters);
       Chan  = atoi(token);

       token = strsep(&TPtr, delimiters);
       Volt  = atoi(token);       

       token = strsep(&TPtr, delimiters);
       Ramp  = atoi(token);

       if (Chan == 0) break;


       else if ( ((Chan==1)&&(!SW1)) ||
                 ((Chan==2)&&(!SW2)) )
		printf("Turn on HV switch\n\n");

       else if ( ((Chan==1)&&(Volt>Vlim1)) ||
                 ((Chan==2)&&(Volt>Vlim2)) ||
                  (Chan>2) ||
		  (Ramp<2) ||
		  (Ramp>255))
		fputs("Input parameters out of range\n\n", stdout);

       else
	 {
           for (i=0;i<5;i++) AChan[i]=0x00;
           for (i=0;i<5;i++) AVolt[i]=0x00;
           for (i=0;i<5;i++) ARamp[i]=0x00;

           sprintf(AChan, "%d", Chan);
           sprintf(AVolt, "%d", Volt);
           sprintf(ARamp, "%d", Ramp);

           for(i=0;i<Wsize;i++) Buffer[i]=0x00;
           strcat(Buffer, "D");
           strcat(Buffer, AChan);
           strcat(Buffer, "=");
           strcat(Buffer, AVolt);
           strcat(Buffer, "\r\n");
	   WritePort(Buffer);
           ReadPort(Word1, Word2);

           for(i=0;i<Wsize;i++) Buffer[i]=0x00;
           strcat(Buffer, "V");
           strcat(Buffer, AChan);
           strcat(Buffer, "=");
           strcat(Buffer, ARamp);
           strcat(Buffer, "\r\n");
	   WritePort(Buffer);
           ReadPort(Word1, Word2);

           for(i=0;i<Wsize;i++) Buffer[i]=0x00;
           strcat(Buffer, "G");
           strcat(Buffer, AChan);
           strcat(Buffer, "\r\n");
	   WritePort(Buffer);
           ReadPort(Word1, Word2);
         }
     }

  close(fd);
  return 1;
}