请教各位大虾为什么一启动线程就出错,在线等待放分

Question

小弟用DELPHI创建了一个线程对象并加入一些串口通讯代码，可是在主线程（界面线程）启动这些代码时出错(accis，不知如何解决，请教代码如下
//////////////////////////////////////////////////////////
unit MIB;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, StdCtrls, Menus;type
  TfrmMIB = class(TForm)
    btnENT: TButton;
    edtNUM: TEdit;
    btnCALL: TButton;
    btnCLR: TButton;
    btnMMIN: TButton;
    panDisplay: TPanel;
    mnuMIB: TMainMenu;
    N3: TMenuItem;
    nExit: TMenuItem;
    N1: TMenuItem;
    nUsehelp: TMenuItem;
    bAbout: TMenuItem;
    cmbCOM: TComboBox;
    ListBox1: TListBox;
    Label1: TLabel;
    dlgSaveLST: TSaveDialog;
    btnSaveData: TButton;
    btnAddData: TButton;
    procedure FormShow(Sender: TObject);
    procedure nExitClick(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure cmbCOMChange(Sender: TObject);  private
    { Private declarations }    procedure OpenComm(strPort: String);
    procedure ExitSystem;
  public
    { Public declarations }  end;var
  frmMIB: TfrmMIB;
  hSerialPort: THandle;implementation
{$R *.dfm}uses DISPLAY;procedure TfrmMIB.FormShow(Sender: TObject);
begin
  btnENT.SetFocus;
  OpenComm(cmbCOM.Text);
  DISPLAY.tDisp.Create(FALSE); //不能启动/////////////////////////////////////////////
end;
procedure TfrmMIB.nExitClick(Sender: TObject);
begin
frmMIB.Close;
end;procedure TfrmMIB.OpenComm(strPort: String);
var
cc:TCOMMCONFIG;
Temp:String;begin
  Temp:=cmbCOM.Text;
  hSerialPort:=CreateFile(PChar(Temp),
                          GENERIC_READ or GENERIC_WRITE,
                          0,
                          nil,
                          OPEN_EXISTING,
                          0,
                          0);
  if (hSerialPort=INVALID_HANDLE_VALUE) then
  begin
    {MessageBox(0,
               '打开串口时发生错误',
               '',
                MB_OK); }
    panDisplay.Caption := '';
    exit;
  end;
  GetCommState(hSerialPort,cc.dcb);
  cc.dcb.BaudRate:=CBR_4800;
  cc.dcb.ByteSize:=8;
  cc.dcb.Parity:=NOPARITY;
  cc.dcb.StopBits:=ONESTOPBIT;  if not SetCommState(hSerialPort, cc.dcb) then
  begin
    {MessageBox(0,
               '不能设置串口',
               '',
               MB_OK);}
    panDisplay.Caption := '';
    CloseHandle(hSerialPort);
    exit;
  end;
end;procedure TfrmMIB.FormClose(Sender: TObject; var Action: TCloseAction);
begin
ExitSystem;
end;procedure TfrmMIB.ExitSystem;
begin
CloseHandle(hSerialPort);
end;
procedure TfrmMIB.cmbCOMChange(Sender: TObject);
begin
OpenComm(cmbCOM.Text);
end;end.///////////////////////////////////////////////////////////////unit DISPLAY;interfaceuses
  Classes,Windows;type
  TDisplay = class(TThread)
  private
    { Private declarations }
    procedure Receives;
  protected
    procedure Execute; override;
  end;var
   tDisp: TDisplay;
     
implementationuses MIB;{ Important: Methods and properties of objects in visual components can only be
  used in a method called using Synchronize, for example,      Synchronize(UpdateCaption);  and UpdateCaption could look like,    procedure TDisplay.UpdateCaption;
    begin
      Form1.Caption := 'Updated in a thread';
    end; }{ TDisplay }procedure TDisplay.Execute;
begin
  { Place thread code here }
  Receives;
end;procedure TDisplay.Receives;
var
  TempString : string;
  inBuff : array[0..2047] of Char;
  BytesRead, dwEvent,dwError : LongWORD;
  cs : TCOMSTAT;
begin
  ClearCommError(MIB.hSerialPort, dwError, @cs);
  if cs.cbInQue>sizeof(inBuff) then
  begin
  PurgeComm(hSerialPort, PURGE_RXCLEAR);
    exit;
  end;
  ReadFile(MIB.hSerialPort, inBuff, cs.cbInQue, BytesRead, nil);
  TempString:=Copy(inBuff, 1, cs.cbInQue);
  MIB.frmMIB.panDisplay.Caption:= TempString;
end;end.

Answer 1

改成
unit2.tDisp:=unit2.TDisplay.Create(FALSE); //不能启  //就行了

Answer 2

我试了一下还是不行，出错信息为Access violation at address 004191F8 in module 'MBT.exe'.Write of address 0000000E.请再帮我找找原因。谢谢

Answer 3

没有sleep是不是线程占有cpu时间太多了

Answer 4

constructor TDisplay.Create;
begin
    inherited Create(False);
    FreeOnTerminate:=true;
    OnTerminate:=Close;
end;

Answer 5

我现在代码已改为
constructor TDisplay.Create(CreateSuspended: Boolean);
begin
  inherited Create(CreateSuspended);
  FreeOnTerminate:=true;
  OnTerminate:=Close;
  //Priority := tpNormal;
end;
可还是通不过，OnTerminate函数需要一个对象(Sender: TObject),注释掉这句还是出现同样错误，各位高手救命呀！

Answer 6

问题已解决，放分
unit MIB;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, StdCtrls, Menus;type
  TfrmMIB = class(TForm)
    btnENT: TButton;
    edtNUM: TEdit;
    btnCALL: TButton;
    btnCLR: TButton;
    btnMMIN: TButton;
    panDisplay: TPanel;
    mnuMIB: TMainMenu;
    N3: TMenuItem;
    nExit: TMenuItem;
    N1: TMenuItem;
    nUsehelp: TMenuItem;
    bAbout: TMenuItem;
    cmbCOM: TComboBox;
    ListBox1: TListBox;
    Label1: TLabel;
    dlgSaveLST: TSaveDialog;
    btnSaveData: TButton;
    btnAddData: TButton;
    procedure FormShow(Sender: TObject);
    procedure nExitClick(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure cmbCOMChange(Sender: TObject);  private
    { Private declarations }
    ThreadsRunning : integer;
    Procedure ThreadDone(Sender: TObject);
    procedure OpenComm(strPort: String);
    procedure ExitSystem;
  public
    { Public declarations }  end;var
  frmMIB: TfrmMIB;
  hSerialPort: THandle;implementation
{$R *.dfm}uses DISPLAY;procedure TfrmMIB.FormShow(Sender: TObject);
begin
  btnENT.SetFocus;
  OpenComm(cmbCOM.Text);
  with TDISPLAY.Create(False) do //关键改进
  OnTerminate := ThreadDone;     //结构很重要
  ThreadsRunning := 1;
end;procedure TfrmMIB.ThreadDone(Sender: TObject);
begin
  {Dec(ThreadsRunning);
  if ThreadsRunning = 0 then
  begin
  end; }
end;procedure TfrmMIB.nExitClick(Sender: TObject);
begin
frmMIB.Close;
end;procedure TfrmMIB.OpenComm(strPort: String);
var
cc:TCOMMCONFIG;
Temp:String;begin
  Temp:=cmbCOM.Text;
  hSerialPort:=CreateFile(PChar(Temp),
                          GENERIC_READ or GENERIC_WRITE,
                          0,
                          nil,
                          OPEN_EXISTING,
                          0,
                          0);
  if (hSerialPort=INVALID_HANDLE_VALUE) then
  begin
    {MessageBox(0,
               '打开串口时发生错误',
               '',
                MB_OK); }
    panDisplay.Caption := '';
    exit;
  end;
  GetCommState(hSerialPort,cc.dcb);
  cc.dcb.BaudRate:=CBR_4800;
  cc.dcb.ByteSize:=8;
  cc.dcb.Parity:=NOPARITY;
  cc.dcb.StopBits:=ONESTOPBIT;  if not SetCommState(hSerialPort, cc.dcb) then
  begin
    {MessageBox(0,
               '不能设置串口',
               '',
               MB_OK);}
    panDisplay.Caption := '';
    CloseHandle(hSerialPort);
    exit;
  end;
end;procedure TfrmMIB.FormClose(Sender: TObject; var Action: TCloseAction);
begin
ExitSystem;
end;procedure TfrmMIB.ExitSystem;
begin
CloseHandle(hSerialPort);
end;procedure TfrmMIB.cmbCOMChange(Sender: TObject);
begin
OpenComm(cmbCOM.Text);
end;end.