main.pas

使用研华DAQ和Delphi实现研华数据采集卡的多种功能.包括数据输入输出。内含多个源码

unit main;

interface

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

type
  TfrmMain = class(TForm)
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Label2: TLabel;
    txtDeviceNum: TEdit;
    txtDeviceName: TEdit;
    cmdSelectDevice: TButton;
    GroupBox2: TGroupBox;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    GroupBox3: TGroupBox;
    Label7: TLabel;
    cmbChannel: TComboBox;
    cmbGateMode: TComboBox;
    txtScanTime: TEdit;
    txtCounter: TEdit;
    cmdCounterStart: TButton;
    cmdCounterStop: TButton;
    cmdExit: TButton;
    ScanTimer: TTimer;
    Label8: TLabel;
    Label9: TLabel;
    txtError: TEdit;
    DAQCounter1: TDAQCounter;
    procedure cmdExitClick(Sender: TObject);
    procedure cmdSelectDeviceClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure cmdCounterStartClick(Sender: TObject);
    procedure cmdCounterStopClick(Sender: TObject);
    procedure ScanTimerTimer(Sender: TObject);
    procedure txtDeviceNumChange(Sender: TObject);
    procedure txtScanTimeChange(Sender: TObject);
    procedure cmbChannelChange(Sender: TObject);
    procedure cmbGateModeChange(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frmMain: TfrmMain;

implementation

{$R *.DFM}
{********************************************************************}
{ Function : Display error message to a dialog box.                  }
{            The format of Long string and short string in Delphi is }
{            different from Null-terminated that used in C.          }
{                                                                    }
{            The long/short string use 1'st char to denote the string}
{            length without termonated char in the tail of string.   }
{                                                                    }
{            The Null-terminated string use Null Char as a string    }
{            termonated and without string length information.       }
{                                                                    }
{            The Message box use Null-Terminated string.             }
{                                                                    }
{ Paramater: sErrMsg: In, Error message string.                      }
{ Return:    None                                                    }
{********************************************************************}
procedure ErrorMsgBox( sErrMsg : WideString);
var
   sErrString : String[51];
   sCaption   : String[51];
begin
   sErrString := sErrMsg + Char(0);
   sCaption := frmMain.Caption + ' Error' + Char(0);
   Application.MessageBox(@sErrString[1], @sCaption, MB_OK or MB_ICONEXCLAMATION);
end;


procedure TfrmMain.cmdExitClick(Sender: TObject);
begin
   application.Terminate
end;

procedure TfrmMain.cmdSelectDeviceClick(Sender: TObject);
Var
   sTmp : string[50];
   i    : integer;
begin
   {Select Device from list}
   DAQCounter1.SelectDevice;

   {Dispaly selection result}
   txtDeviceNum.Text := IntToStr(DAQCounter1.DeviceNumber);
   txtDeviceName.Text := DAQCounter1.DeviceName;

   {Clear previous selection}
   cmbChannel.Clear;
   cmdCounterStart.Enabled := False;

   {Add Counter channel for selection}
   If DAQCounter1.OpenDevice Then
   Begin
      ErrorMsgBox(DAQCounter1.ErrorMessage);
      Exit;
   End;

   if DAQCounter1.MaxCounterNumber = 0 then
   begin
      ShowMessage('Function Not Supported');
      DAQCounter1.CloseDevice;
      Exit;
   end;
   For i := 0 To (DAQCounter1.MaxCounterNumber-1) do
   begin
      str(i, sTmp);
      cmbChannel.Items.Add(sTmp);
   end;
   If DAQCounter1.MaxCounterNumber > 0 Then
      cmbChannel.ItemIndex := DAQCounter1.Channel;

   DAQCounter1.CloseDevice;

   {Manage UI after selection}
   cmdCounterStart.Enabled := True;
end;

procedure TfrmMain.FormCreate(Sender: TObject);
begin
   {Give the default UI}
   cmdSelectDeviceClick(Sender);
   cmdCounterStop.Enabled := False;
   cmbGateMode.ItemIndex := DAQCounter1.GateMode;
   cmbChannel.ItemIndex := DAQCounter1.Channel;
   ScanTimer.Enabled := False;
end;

procedure TfrmMain.cmdCounterStartClick(Sender: TObject);
begin
   {Open deice for acquiring }
   If DAQCounter1.OpenDevice Then
   Begin
      ErrorMsgBox(DAQCounter1.ErrorMessage);
      Exit;
   End;
   DAQCounter1.Channel := cmbChannel.ItemIndex;
   DAQCounter1.GateMode := cmbGateMode.ItemIndex;

   {Start action }
   DAQCounter1.EnableCounter(True);
   ScanTimer.Enabled := True;

   {Manage UI, Avoid error command using}
   cmdCounterStart.Enabled := False;
   cmdCounterStop.Enabled := True;
   cmdExit.Enabled := False;
   cmdSelectDevice.Enabled := False;
end;

procedure TfrmMain.cmdCounterStopClick(Sender: TObject);
begin
   {Stop counter action}
   ScanTimer.Enabled := False;
   DAQCounter1.EnableCounter(False);

   {Close counter device}
   If DAQCounter1.CloseDevice Then
   Begin
      ErrorMsgBox(DAQCounter1.ErrorMessage);
      Exit;
   End;

   {Manage UI}
   cmdCounterStart.Enabled := True;
   cmdCounterStop.Enabled := False;
   cmdExit.Enabled := True;
   cmdSelectDevice.Enabled := True;
end;

procedure TfrmMain.ScanTimerTimer(Sender: TObject);
begin
   txtError.Text := DAQCounter1.ErrorMessage;
   If DAQCounter1.ErrorCode <> 0 Then
   Begin
      ScanTimer.Enabled := False;
   End;
   txtCounter.Text := IntToStr(DAQCounter1.CounterValue);
end;

procedure TfrmMain.txtDeviceNumChange(Sender: TObject);
begin
   DAQCounter1.DeviceNumber := StrToInt(txtDeviceNum.text);
   txtDeviceName.Text := DAQCounter1.DeviceName;
end;

procedure TfrmMain.txtScanTimeChange(Sender: TObject);
begin
   ScanTimer.Interval := StrToInt(txtScanTime.Text);
end;

procedure TfrmMain.cmbChannelChange(Sender: TObject);
begin
   DAQCounter1.Channel := cmbChannel.ItemIndex;
end;

procedure TfrmMain.cmbGateModeChange(Sender: TObject);
begin
   DAQCounter1.Channel := cmbGateMode.ItemIndex;
end;

procedure TfrmMain.FormClose(Sender: TObject; var Action: TCloseAction);
begin
   ScanTimer.Enabled := False;
   DAQCounter1.EnableCounter(False);
   DAQCounter1.CloseDevice;
end;

end.