unit1.~pas

RS232串口通讯随书源码

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, TComm1;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label3: TLabel;
    txtInput: TEdit;
    cmdCalc: TButton;
    cmdClose: TButton;
    Comm1: TComm;
    mReceive: TMemo;
    cmdClearCom: TButton;
    cmdReceive: TButton;
    procedure cmdCalcClick(Sender: TObject);
    procedure cmdClearComClick(Sender: TObject);
    procedure cmdReceiveClick(Sender: TObject);
    procedure cmdCloseClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  Procedure TimeDelay(DT:DWORD);//延迟函数
implementation

{$R *.DFM}

//以下程序将字符串中的字符送出
procedure TForm1.cmdCalcClick(Sender: TObject);
var
  InputStr:String;
begin
  //命令指定，并加上结尾字符Cr
  InputStr:=Trim(txtInput.Text) + Chr(13);
  Comm1.OutputString(InputStr);//送出数据
end;

//结束程序
procedure TForm1.cmdCloseClick(Sender: TObject);
begin
  Close;
end;

//以下是延迟函数，单位毫秒
Procedure TimeDelay(DT:DWORD);
var
 TT:DWORD;
begin
  //取得现在的Tick值
  TT:=GetTickCount();
  //计算Tick差值是否超过设置值
  while GetTickCount()-TT<DT do
   Application.ProcessMessages; //释放控制权
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  //打开通信端口
  Comm1.PortOpen := True;
end;


//清除接收缓冲区
procedure TForm1.cmdClearComClick(Sender: TObject);
begin
  Comm1.DataCount :=0;
end;

//接收串行端口数据
procedure TForm1.cmdReceiveClick(Sender: TObject);
var
 Buf:String;
 DotPos:Integer;
 ReceiveStr:String;
begin
  ReceiveStr := Trim(Comm1.Input);
  //结尾字符是否已返回
  If Pos('!',ReceiveStr) < 1 Then
   Exit
  Else
   begin
    Repeat
      //检查逗号的位置
      DotPos := Pos(',',ReceiveStr);
      //数据放进Memo
      mReceive.Text := mReceive.Text + Copy(ReceiveStr,1,DotPos-1) +Chr(13) + Chr(10);
      //留下未处理的数据
      ReceiveStr := Copy(ReceiveStr,DotPos+1,Length(ReceiveStr)-DotPos);
    until DotPos=0;  //直到找不到逗号
    ReceiveStr := '';
   end;
end;

end.