{*--------------------------------------------------------------------
 *              C LANGUAGE SAMPLE 0 :
 *
 * Sample program for the Analog and Digital I/O card
 * demonstrating register level data aquistion from the
 *
 * Last Modification : 16 May 2002.
 *------------------------------------------------------------------*}

uses Crt;

var
   base : Word;

function AskForBaseAddress(OldOne : String) : Word;
const
   Msg : string[8] = '0';
var
   NewOne, Success, Dummy, Error : Word;
   AddrInputPosX, AddrInputPosY : Word;
begin
   if (OldOne = 'OLD') then OldOne := Msg;
   WriteLn('Please enter the Base Address (100-FFFF) for your card (in hex)');
   WriteLn('or press ENTER for ', OldOne, '.  ');
   Write('>');
   AddrInputPosX := WhereX; AddrInputPosY := WhereY;
   Success := 0;
   repeat
      GotoXY(AddrInputPosX, AddrInputPosY);
      ClrEol;
      Readln(Msg);
      Val('$' + Msg, NewOne, Error);
      if NewOne >= $100 then begin
         Success := 1;
         Dummy := NewOne;
      end else if (Msg = '') then begin
         GotoXY(AddrInputPosX, AddrInputPosY);
         WriteLn(OldOne);
         Msg := OldOne;
         Success := 1;
         Val('$' + Msg, Dummy, Error);
      end;
   until (Success = 1);
   AskForBaseAddress := Dummy;
end;

procedure intro;
begin
   clrscr;
   writeln('Sample 0');
   writeln;
   writeln('This sample reads the sixteen analog inputs and ');
   writeln('displays them for you.');
   writeln; writeln;
   writeln('Board Configuration Requirements:');
   writeln;
   writeln('RANGE:        5 Volt Range');
   writeln('POLARITY:     Bipolar');
   writeln;
   writeln('Please press any key to set base address.');
   readkey;

   clrscr;
   base := AskForBaseAddress('300');
   clrscr;

end; { end of Intro }


var
   channel, counts, i : integer;
   volts : real;

begin
   intro;
   port[base+2] := $F0;                 { Set scan from Ch0 to Ch15 }

   clrscr;
   writeln('          Channel     Counts     Volts');
   writeln('          -------     ------     -----');

   repeat
      repeat
         port[base] := 0;           { Start A/D conversion }

         i := 0;                     { Wait for EOC or timeout }
         while ( ((port[base+8] and $80) = $80) and (i < 32000) ) do
              i := i+1;

         if (i >= 32000) then begin   { if timeout, display error & quit }
            channel := port[base] and $0F;
            writeln('Error: Timeout on channel ', channel);
            exit;
         end; { end if }

         channel := port[base] and $0F;             { Get channel number }
         counts  := portw[base] shr 4;               { Get channel counts }

         { Scaling 5v range on 12 bit device = 0.00244v/count }
         volts  := (counts-2048)*0.00244;

         writeln(channel:14, counts:12, volts:12:3);        { Show data }
      until ((port[base] and $0F) = $0F);  { end repeat }
   until (KeyPressed);

end. { end of main }