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

unsigned int BASE=0x300;
unsigned int IRQPIN=5;





//INSW - input string of words
void insw(unsigned short Port, void far *Buf, int Count)
{
   _ES = FP_SEG(Buf);   /* Segment of Buf */
   _DI = FP_OFF(Buf);   /* Offset of Buf  */
   _CX = Count;         /* Number to read */
   _DX = Port;          /* Port           */
   asm   REP INSW;
}



char far *VM = (char far *)MK_FP(0xB800, 0);
const char HexDigit[16] = "0123456789ABCDEF";

char *WordToPChar(unsigned short Data)
{
  static char Lit[5];

  Lit[4] = 0;
  Lit[3] = HexDigit[Data & 0xF];
  Lit[2] = HexDigit[(Data >> 4) & 0xF];
  Lit[1] = HexDigit[(Data >> 8) & 0xF];
  Lit[0] = HexDigit[(Data >> 12) & 0xF];
  return Lit;
}

void PrintWord(int XR, int Y, unsigned short Data)
{
  char far *Tar = VM + (Y * 80 + XR) * 2;
  *Tar = HexDigit[Data & 0xF];
  Data >>= 4;
  Tar -= 2;
  *Tar = HexDigit[Data & 0xF];
  Data >>= 4;
  Tar -= 2;
  *Tar = HexDigit[Data & 0xF];
  Data >>= 4;
  Tar -= 2;
  *Tar = HexDigit[Data & 0xF];
}

void PrintNybble(int X, int Y, unsigned char Data)
{
  char far *Tar = VM + (Y * 80 + X) * 2;
  *Tar = HexDigit[Data & 0xF];
}

void PrintChar(int X, int Y, char Data)
{
  char far *Tar = VM + (Y * 80 + X) * 2;
  *Tar = Data;
}

unsigned AskForBaseAddress(unsigned int OldOne)
{
    char msg[8];
    unsigned int NewOne = 0, Success = 0, Dummy;
    int AddrInputPosX, AddrInputPosY;

    puts("\n\nPlease enter the Base Address (100-FFFF) 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);
        if (NewOne >= 0x100)
        {
            Success = 1;
            Dummy = NewOne;
        } else if (msg[1] == 0) {
            gotoxy(AddrInputPosX, AddrInputPosY);
            printf("%X", OldOne);
            Success = 1;
            Dummy = OldOne;
        }
    } while(!Success);
    return (Dummy);
} /* end of AskForBaseAddress */

unsigned AskForIRQ(unsigned int OldOne)
{
    char msg[8];
    unsigned int NewOne = 0, Success = 0, Dummy;
    int AddrInputPosX, AddrInputPosY;

    puts("\n\nPlease enter the IRQ (2-F) for your card (in hex)");
    printf("or press ENTER for %X.\n>", OldOne);
    AddrInputPosX = wherex(); AddrInputPosY = wherey();
    do {
        gotoxy(AddrInputPosX, AddrInputPosY);
        clreol();
        msg[0] = 3; msg[1] = 0;
        cgets(msg);
        sscanf(msg + 2, "%x", &NewOne);
        if ( (NewOne >= 0x2) && (NewOne <= 0xF) )
        {
            Success = 1;
            Dummy = NewOne;
        } else if (msg[1] == 0) {
            gotoxy(AddrInputPosX, AddrInputPosY);
            printf("%X", OldOne);
            Success = 1;
            Dummy = OldOne;
        }
    } while(!Success);
    return (Dummy);
} /* end of AskForIRQ */



//8254 functions
void CtrMode(unsigned char Ctr, unsigned char Mode)
{
    unsigned char Ctrl = (Ctr << 6) | 0x30 | (Mode << 1);
    outportb(BASE+0x08+3, Ctrl);
}

void CtrLoad(unsigned char Ctr, unsigned short Data)
{
    outportb(BASE+0x08+Ctr, Data & 0xFF);
    outportb(BASE+0x08+Ctr, Data >> 8);
}



//IRQ array and functions

//In C++, ISRs take (...) arguments
#ifdef __cplusplus
  #define __CPPARGS ...
#else
  #define __CPPARGS
#endif

void interrupt far (*oldisr[16])(__CPPARGS);  //global to store old handler pointer

void SendEOI(void)
{
   outportb(0xA0, 0x20);
   outportb(0x20, 0x20);
}

unsigned char initirq(char IRQnumber,void interrupt (*ISR)(__CPPARGS))
{
   unsigned char intmask, oldmask;

   if (IRQnumber <=7) {
      oldmask = inportb(0x21);
      oldisr[IRQnumber] = getvect(IRQnumber + 8);
      setvect(IRQnumber + 8,ISR);
      intmask = oldmask & (~(1 << IRQnumber));
      outportb(0x21,intmask);
   } else {
      oldmask = inportb(0xA1);
      oldisr[IRQnumber] = getvect(IRQnumber + 0x70 - 8);
      setvect(IRQnumber - 8 + 0x70, ISR);
      intmask = oldmask & (~(1 << (IRQnumber - 8)));
      outportb(0xA1, intmask);
   }
   return(oldmask);
}

void restoreirq(char IRQnumber)
{
   unsigned char intmask;

   if (IRQnumber <=7 ){
      intmask = inportb(0x21);
      intmask |= (1 << IRQnumber);
      setvect(IRQnumber + 8,oldisr[IRQnumber]);
      outportb(0x21, intmask);
   } else {
      intmask = inportb(0xA1);
      intmask |= (1 << (IRQnumber - 8));
      setvect(IRQnumber - 8 + 0x70, oldisr[IRQnumber]);
      outportb(0xA1, intmask);
   }
}



//104-AIO1616W config variables and utility functions
unsigned char ADRange, dacArange, dacBrange;

void init(void)
{
  unsigned char jumpers;
  outportb(BASE + 0x1B,0xFF);
  delay(1);

  jumpers = inportb(BASE+0x12);//jumper configuration readback
  ADRange = jumpers & 0x07;//d0,d1,d2 are 16ch, 5V, Bip
  dacBrange = (jumpers>>3) & 0x01;//d4,d3 are 5V for daca,b
  dacArange = (jumpers>>4) & 0x01;

  outportb(BASE+0x13, 0x04); //Enable FIFO half full IRQs
  outportb(BASE+0x07, 0x00); //Set oversample to +0
  CtrMode(1, 2);
  CtrMode(2, 2);

  CtrLoad(1, 0x0002); //Ctr 1 & 2 divisor of 50h with 10MHz clock gives 125kHz tick
  CtrLoad(2, 0x0028);
  outport(BASE + 0x02, 0x0000); //Clear gains 0-7
  outport(BASE + 0x04, 0x0000); //Clear gains 8-F
  outportb(BASE + 0x06, 0x10); //Set channel scan from 0 to 1
}


#define STARTTIMEDCONVERSIONS StartTimedConversions()
void StartTimedConversions(void)
{
  outportb(BASE+0x1B, 0x01); //Clear FIFO
  outportb(BASE+0x11, 0x01); //Select Ctr as ADC trigger, one channel per output pulse
}

#define STOPTIMEDCONVERSIONS outportb(BASE+0x11, 0x00)

//Bytes in half FIFO
#define FIFOHALF 1024
//Bytes in quarter FIFO = samples in half FIFO
#define FIFOQUAR (FIFOHALF / 2)

unsigned short Buf[FIFOQUAR];
unsigned long IRQCount;

void interrupt far newisr(__CPPARGS)
{
  insw(BASE + 0x0, Buf, FIFOQUAR);
  ++IRQCount;
  PrintChar(13, 6, IRQCount);
  SendEOI();
  inportb(BASE+ 0x13); //Clear FIFO half full IRQs
}

void main(void)
{
  unsigned long OIRQCount = 0;
  IRQCount = 0;

  directvideo = 1;
  clrscr();

  BASE = AskForBaseAddress(BASE);
  IRQPIN = AskForIRQ(IRQPIN);

  clrscr();
  cputs("104-AIO16 Family High-Speed Sample\r\n");
  cputs("This sample acquires from A/D channels 0 and 1 at 125kHz per channel.\r\n");
  cputs("Data is displayed in the idle time between acquisition.\r\n\r\n");

  init();
  cprintf("A/D:   %s %s\r\n\r\n",
         (ADRange & 0x01)?
           ((ADRange & 0x04)?"ñ5V":"ñ10V")
         :
           ((ADRange & 0x04)?"0-10V":"0-10V(Low Res)") //0-10V(Low Res) is
         ,                                           //in theory 0-20V,
         (ADRange & 0x02)?"16ch":"8ch"                 //but the amps cap
                                                     //at 10V
  );
  cputs("Taking data: \r\n\r\n");

  gotoxy(11, 9);
  cputs("Ch 0      Ch 1");
  gotoxy(11, 10);
  cputs("....      ....");

  gotoxy(1, 12);
  cputs("Press any key to exit.\r\n");

  initirq(IRQPIN, newisr);
  STARTTIMEDCONVERSIONS;

  while(-1)
  {
    if ( IRQCount != OIRQCount )
    {
      OIRQCount = IRQCount;

      PrintWord(13, 9, Buf[0]);
      PrintWord(23, 9, Buf[1]);
    }

    if ( kbhit() )
    {
      getch();
      break;
    }
  }

  restoreirq(IRQPIN);

  STOPTIMEDCONVERSIONS;
}