unit Main;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ComCtrls, ExtCtrls, StdCtrls;

type
  TMainForm = class(TForm)
    GroupRange: TRadioGroup;
    GroupOutput: TGroupBox;
    Value: TTrackBar;
    LOutput: TLabel;
    Label2: TLabel;
    GroupChannel: TRadioGroup;
    StatusBar1: TStatusBar;
    Memo1: TMemo;
    ExitButton: TButton;
    Initialize: TButton;
    ISAPanel: TGroupBox;
    Label1: TLabel;
    ISAEdit: TEdit;
    procedure UpdateDAC;
    function ConvertForOutput(V:longword):longword;
    procedure ValueChange(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure ExitButtonClick(Sender: TObject);
    procedure InitializeClick(Sender: TObject);
    procedure FormActivate(Sender: TObject);
    procedure GroupRangeClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

{$R *.DFM}

uses ACCES32;

  //global variables for internal use
const
  span:double=-10.0;
  Offset:double=-5;
  CurVal:word=0;
  maxch:integer=2;

var                                              
  Address : WORD;
  RunFlag:Boolean;

function TMainForm.ConvertForOutput(v:longword):longword;
  var i:integer;
begin
  v:=v;//bipolar ranges are inverted offset binary
  if (GroupChannel.ItemIndex < maxch) then //the last item in the channel list is ALL
    outport(Address+(GroupChannel.ItemIndex*2),v*16)
  else                           //"all channels" is selected, use simul mode
    for i:=0 to maxch-1 do
      outport(Address+(i*2)+4,v*16);//use simul mode
  result:=v;
end;

function IntToBin(input:longword):string;
  var
    temp:string;
    i:word;
    f:double;
begin
//this for loop converts to binary
  temp:='';
  for i:=11 downto 0 do begin
    if (input AND (1 shl i))=0 then temp:=temp+'0' else temp:=temp+'1';
  end;//for;

  temp:=temp+'xxxx';
  f:=((input) * span / 4096 - offset);//volts

  temp:=temp+'  '+inttohex(input,3)+' '+floattostrf(f,ffFixed,6,3);
  if (MainForm.GroupRange.ItemIndex=4) then
    result:=temp+' mA'
  else
    result:=temp+' Volts';
end;


procedure TMainForm.UpdateDAC;
begin
  LOutput.Caption:=IntToBin(ConvertForOutput(CurVal));
end;

procedure TMainForm.ValueChange(Sender: TObject);
begin
  CurVal:=value.position;
  UpdateDAC;
end;

procedure TMainForm.FormCreate(Sender: TObject);
var
    i: Integer;
begin
    GroupChannel.Items.Clear;//create channel list
    for i:=1 to maxch do
      GroupChannel.Items.Append('Channel '+inttostr(i-1));
    GroupChannel.Items.Append('All Channels');
    GroupChannel.ItemIndex:=0;
    memo1.lines.append('');
    memo1.lines.append('Please configure the dialog options shown to reflect the'+
     ' settings on the card that is installed.  The card''s output voltage shown'+
     ' onscreen will only be correct if these settings are correct.'+
     ' Refer to the card''s manual for specifics about jumper settings and switches.');
    Memo1.ScrollBars:=ssVertical;

   if (InPortB($61) = $AA55) then begin
      Application.MessageBox('ACCESNT.SYS not detected. Please copy ACCESNT.SYS into [NT]/system32/drivers and re-run this sample.', 'Warning', IDOK);
   end;
end;

procedure TMainForm.ExitButtonClick(Sender: TObject);
begin
  close;
end;

procedure TMainForm.InitializeClick(Sender: TObject);
  var
    code,data:integer;
begin
{$R-}
  val('$'+ISAEdit.Text,data,code);
{$R+}
  if ((data>$100) and (data<$3ff)) then begin
    Address:=data;
    runflag:=True;
  end else Beep;
  if runflag then begin
    GroupOutput.visible:=True;
    GroupOutput.enabled:=True;
  end;
end;

procedure TMainForm.FormActivate(Sender: TObject);
begin
  FocusControl(IsaEdit);
end;

procedure TMainForm.GroupRangeClick(Sender: TObject);
begin
  case GroupRange.itemindex of
    0:begin offset:=-5;span:=-10;end;
    1:begin offset:=-10;span:=-20;end;
    2:begin offset:=0;span:=5;end;
    3:begin offset:=0;span:=10;end;
    4:begin offset:=-4;span:=16;end;
  end;//case
  UpdateDAC;
end;

end.