unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, OleCtrls, MSCommLib_TLB, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    MSComm1: TMSComm;
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Edit1: TEdit;
    Button2: TButton;
    Label5: TLabel;
    ComboBox2: TComboBox;
    ComboBox3: TComboBox;
    Label6: TLabel;
    Label9: TLabel;
    Edit8: TEdit;
    Label10: TLabel;
    Edit10: TEdit;
    Label11: TLabel;
    Edit11: TEdit;
    Label12: TLabel;
    Edit12: TEdit;
    Label13: TLabel;
    Edit9: TEdit;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure MSComm1Comm(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
    procedure comopen;  //設置串口狀態
  public
    { Public declarations }
    comstate:integer;  //狀態變量，用來表示電子稱是連接狀態，斷開狀態
    scom:string;       //串口號
    sbt:string;        //波特率
    comorder,startchar,endchar,charstartno,charlong:string;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  comstate:=0;
  scom:='COM1';
  sbt:='9600,n,8,1';
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
   if comstate=0 then
   begin
      comopen;
      Button1.Caption :='斷開電子稱';
      comstate:=1;
   end
   else
   begin
     if MSComm1.PortOpen =true then
     MSComm1.PortOpen :=false;
      Button1.Caption :='連接電子稱';
      comstate:=0;
   end;
end;
procedure TForm1.comopen;
var s1:string;
begin
    if MSComm1.PortOpen then
       MSComm1.PortOpen :=false;
    if scom='COM1' then
      MSComm1.CommPort:=1
    else
      MSComm1.CommPort:=2;
    MSComm1.Settings :=sbt;
    MSComm1.InputMode:=0;
    MSComm1.InputLen :=1;
    MSComm1.RThreshold := 1;
    MSComm1.SThreshold := 1;
    MSComm1.PortOpen :=true;
end;
procedure TForm1.MSComm1Comm(Sender: TObject);
var ssss,sstr,slend,strcom,sweight: string;
begin
  //提示：串口數據是按字節發送和接收的，一個字節一個字節的接收的
  if MSComm1.PortOpen=true then
     ssss:=MSComm1.Input; //讀數據
  if ssss=chr(strtoint(startchar)) then  //如果是開始字符，則清空字符串
    strcom:='';
  if ssss=chr(strtoint(endchar)) then
  begin           // 如果是結束字符，則輸出重量
    sweight:=copy(strcom,strtoint(charstartno)+1,strtoint(charlong));
    Edit1.Text  :=sweight;
  end
  else            //如果不是是結束字符，則繼續接受數據
   strcom:=strcom+ssss;

end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  //設置狀態
  scom   := ComboBox2.Text;
  sbt    := ComboBox3.Text;
  comorder       := Edit8.Text;
  startchar      := Edit10.Text;
  endchar        := Edit11.Text;
  charstartno    := Edit12.Text;
  charlong       := Edit9.Text;
end;

end.