#include <stdio.h>
#include <dos.h>
#include <conio.h>


#define RLD 0x80
#define XRLD 0x00
#define YRLD XRLD
#define Rst_BP 0x01
#define Rst_CTR 0x02
#define Rst_FLAGS 0x04
#define Rst_E 0x06
#define Trf_PR_CTR 0x08
#define Trf_CTR_OL 0x10
#define Trf_PS0_PSC 0x18

#define CMR 0xA0
#define XCMR 0x20
#define YCMR XCMR
#define BINCnt 0x00
#define BCDCnt 0x01
#define NrmCnt 0x00
#define RngLmt 0x02
#define NRcyc 0x04
#define ModN 0x06
#define NQDX 0x00
#define QDX1 0x08
#define QDX2 0x10
#define QDX4 0x18

#define IOR 0xC0
#define XIOR 0x40
#define YIOR 0x00
#define DisAB 0x00
#define EnAB 0x01
#define LCTR 0x00
#define LOL 0x02
#define RCTR 0x00
#define ABGate 0x04
#define CYBW 0x00
#define CPBW 0x08
#define CB_UPDN 0x10
#define IDX_ERR 0x18

#define IDR 0xE0
#define XIDR 0x60
#define YIDR XIDR
#define DisIDX 0x00
#define EnIDX 0x01
#define NIDX 0x00
#define PIDX 0x02
#define LIDX 0x00
#define RIDX 0x04

void Init_7266(unsigned short Addr)
{
    outportb(Addr+0x14,0x01); //put CPLD on card into divide-by-1 FCK mode
    outportb(Addr+0x12,0xFF); //enable index for all channels in CPLD
    for (int count = 0; count < 4; count++)
    {
      unsigned long XCt = 0xFFFFFF;
      unsigned long YCt = 0xFFFFFF;

       //Setup IOR reg
       outportb(Addr + 1, IOR + DisAB + LOL + ABGate + CYBW);

       //Setup RLD reg
       outportb(Addr + 1, RLD + Rst_BP + Rst_FLAGS);
       outportb(Addr + 0, 0x00);
       outportb(Addr + 2, 0x00);
       outportb(Addr + 1, RLD + Rst_E + Trf_PS0_PSC);

       //Setup IDR reg
       outportb(Addr + 1, IDR + EnIDX + NIDX + LIDX);

       //Setup CMR reg
       outportb(Addr + 1, CMR + BINCnt + ModN + QDX1);

       //Setup PR reg for modulo N counter to XCt
       outportb(Addr + 0, XCt);
       XCt >>= 8;
       outportb(Addr + 0, XCt);
       XCt >>= 8;
       outportb(Addr + 0, XCt);

       //Setup PR reg for modulo N counter to YCt
       outportb(Addr + 2, YCt);
       YCt >>= 8;
       outportb(Addr + 2, YCt);
       YCt >>= 8;
       outportb(Addr + 2, YCt);

       //Enable counters
       outportb(Addr + 1, IOR + EnAB + IDX_ERR);
       Addr += 4;
    }
}

void Write_7266_PR(unsigned short Addr, unsigned long Data)
{

   outportb(Addr + 1, RLD + Rst_BP);
   outportb(Addr + 0, Data);
   Data >>= 8;
   outportb(Addr + 0, Data);
   Data >>= 8;
   outportb(Addr + 0, Data);
}

long int Read_7266_OL(unsigned short Addr)
{
   union pos_tag {     /* allows access of 32-bit integer as 4 bytes */
   long int l;
   struct byte_tag {char b0; char b1; char b2; char b3;} byte;
   }pos;

   outportb(Addr + 1, 0x10);   /* reset address pointer */
   outportb(Addr + 1, 0x01);      /* command to latch counter */
   pos.byte.b0 = inportb(Addr);
   pos.byte.b1 = inportb(Addr);
   pos.byte.b2 = inportb(Addr);
   /* extend sign of position */  //requires signed characters
   if (pos.byte.b2 < 0) pos.byte.b3 = -1;
   else pos.byte.b3 = 0;

   return pos.l;
}

unsigned AskForBaseAddress(unsigned int OldOne)
{
    char msg[7];
    int NewOne = 0, Success = 0, Dummy;
    int AddrInputPosX, AddrInputPosY;

    puts("\nPlease enter the Base Address for your card (in hex)");
    printf("or press ENTER for %X.\n>", OldOne);
    AddrInputPosX = wherex(); AddrInputPosY = wherey();
    do {
      gotoxy(AddrInputPosX, AddrInputPosY);
      clreol();
      msg[0] = 5; msg[1] = 0;
      cgets(msg);
      sscanf(msg + 2, "%x", &NewOne);
      Success = 1;
      Dummy = NewOne;
        if (msg[1] == 0) {
        gotoxy(AddrInputPosX, AddrInputPosY);
        printf("%X", OldOne);
        Success = 1;
        Dummy = OldOne;
      }
    } while(!Success);
    return (Dummy);
} /* end of AskForBaseAddress */


float getTicks(void)
{
   int done = 0;
   char line[256];
   float result;

   while (!done)
   {

      printf("Enter the number of ticks per inch: ");
      gets(line);

      if (sscanf(line, "%f", &result) == 1)
         done = 1;

   };

   return result;


}

void main (void)
{
    unsigned int address = 0x300;
    int done = 0;
    float ticksPerInch;
    long int reading;

    address = AskForBaseAddress(address);

    Init_7266(address); //does all counters wierdly

    clrscr();

    ticksPerInch = getTicks();


    while (!done)
    {
       for (int count = 0; count < 8; count++)
       {
          gotoxy(1, count + 1);

          reading = Read_7266_OL(address + count * 2);

          printf("Channel %d: Reading:%08lx(hex) Distance:%.2f (inches) ", count, reading,
                  reading/ticksPerInch );
       }

       printf("\nNow reading all channels.\nPress any key to exit...");

       if (kbhit())
          done = 1;

    };

    getch();//clear keystroke
}