串口通讯问题，用定时器实现，急！！！！！！！！！

procedure TfrmMain.Timer1Timer(Sender: TObject);
var
  i:Integer;
  str：string;
 begin
  flagspeed := false;
  ClearCommError(ComHandle1,dwCOM_ErrFlag1,@csCOM_State1);
  if csCOM_State1.cbInQue=0 then
  begin
    Exit;
  end;
  ReadFile(ComHandle1,baRBuf1[0],csCOM_State1.cbInQue,dwRB1,nil);
  str:='';
  for i:=0 to dwRB1-1 do
  begin
    if (baRBuf1[i]=1) then
    begin
      SpeedCount1:=0;
      CanTakeSpeed1:=True;
      SpeedBuf1[0]:=0;
      SpeedBuf1[1]:=0;
      SpeedBuf1[2]:=0;
    end;
    if ((CanTakeSpeed1=True) and (baRBuf1[i]>10)) then
    begin
      SpeedBuf1[SpeedCount1]:=baRBuf1[i];
      SpeedCount1:=SpeedCount1+1;
    end;
    if (SpeedCount1=3) then
    begin
      Application.ProcessMessages;
      Speed1:=SpeedProcess1;
      str:='1'+' '+IntToStr(StrToInt('$'+IntToHex(SpeedBuf1[0],2)));
      str:=str+' '+IntToStr(StrToInt('$'+IntToHex(SpeedBuf1[1],2)));
      str:=str+' '+IntToStr(StrToInt('$'+IntToHex(SpeedBuf1[2],2)));
      Str:=Str+' Take_'+IntToStr(Speed1);
      if (str<>'') then
      begin
         Application.ProcessMessages;
         SpeedDisp1.Lines.Add(str);
      end;
      if (SpeedDisp1.Lines.Count>=200) then
        SpeedDisp1.Lines.Delete(0);
      if (Speed1>=SpeedTake) then
      begin
    //Timer1.Enabled:=False;
   //拍照
    if Capture then
    begin
      PicProcess;
      tickStart1:=GetTickCount;
      while (GetTickCount-tickStart1<10000) do
        Application.ProcessMessages;
    end;
    Timer1.Enabled:=True;
    //拍照结束后清除速度
    ClearCommError(HComcam1,dwCOM_ErrFlagcam1,@csCOM_Statecam1);
     SpeedCount1:=0;
   CanTakeSpeed1:=False;
  end;
  end;
  end;
function TfrmMain.Capture: Boolean;
var
  nowStatus             :Integer;
  destfname             : string ;
  fsdestfname           : Tfilestream ;
  iTotalRB,itotall      :Integer;
begin
  Result:=False;
  tickStart1:=GetTickCount;
  bTimeOut1:=False;
  //拍照
  baSendBufCam1[0]:=$b1;
  WriteFile(HComCam1,baSendBufCam1,1,dwSendBytesCam1,nil);
  sb1.Panels[0].Text:='正在连接相机1...';
  Application.ProcessMessages;
  //接收图片
  iTotalRB:=0;
  itotall:=0;
  nowStatus:=0;
  //接收$a0
  while ((nowStatus=0) and (not bTimeOut1)) do
  begin
    if (GetTickCount-tickStart1>5000) then    ///////////////////////
      bTimeOut1:=True;
    ClearCommError(HComCam1,dwCOM_ErrFlagCam1,@csCOM_StateCam1);
    if csCOM_StateCam1.cbInQue=0 then
    begin
      continue ;
    end;
    ReadFile(HComCam1,baRBufCam1[0],csCOM_StateCam1.cbInQue,dwRBCam1,nil);
    if (baRBufCam1[0]=$a0) then
    begin
      nowStatus:=1;
    end;
  end;
  if nowStatus = 1 then
  begin
  //Timer1.Enabled := True;/////////////////////////////////////////////////////
  //发送$A9
  baSendBufCam1[0]:= $a9;
  WriteFile(HComCam1,baSendBufCam1,1,dwSendBytesCam1,nil);
  nowStatus:=2;  //等待接收数据
  sb1.Panels[0].Text:='正在接收数据...';
  Application.ProcessMessages;
  while ((nowStatus=2) and (not bTimeOut1)) do
  begin
    if (GetTickCount-tickStart1>120000) then
      bTimeOut1:=True;
    ClearCommError(HComCam1,dwCOM_ErrFlagCam1,@csCOM_StateCam1);
    if csCOM_StateCam1.cbInQue=0 then
    begin
      continue ;
    end;
    ReadFile(HComCam1,baRBufCam1[iTotalRB],csCOM_StateCam1.cbInQue,dwRBCam1,nil);
    iTotalRB:=iTotalRB+dwRBCam1;
    if (itotalRB > 34) and (itotall = 0) then
    begin
      itotall:=baRBufCam1[25]*16777216+baRBufCam1[24]*65535+baRBufCam1[23]*256+baRBufCam1[22]+22;
    end;
    if (itotalRB>34)and(itotalRB>=itotall) then
    begin
      destfname:='c:\1.jpg';
      fsdestfname:=Tfilestream.Create(destfname,fmcreate);
      fsdestfname.Write(baRBufCam1[34],itotall-12);
      fsdestfname.Write(baRBufCam1[0],26);
      fsdestfname.Free;
      nowStatus:=3;
      Result:=True;
      sb1.Panels[0].Text:='图片下载完成';
      Application.ProcessMessages;
    end;
  end;
  if bTimeOut1 then
  begin
    //重启相机
    baSendBufCam1[0]:=$a7;
    WriteFile(HComCam1,baSendBufCam1,1,dwSendBytesCam1,nil);
    sb1.Panels[0].Text:='图片下载超时,正重启...';
    Application.ProcessMessages;
    //延时1分钟，等待相机重启
    tickStart1:=GetTickCount;
    while (GetTickCount-tickStart1<60000) do
      Application.ProcessMessages;
      sb1.Panels[0].Text:='图片下载超时,重启完成';
    Application.ProcessMessages;
  end;
end;
end;
procedure TfrmMain.PicProcess;
var
  picName:string;
  Speeddiff:integer;
begin
if flagspeed = false then
speeddiff := speed1
else
speeddiff := speed2;
try
  MyJpeg.LoadFromFile('c:\1.jpg');
  bmp.assign(MyJpeg);
  //图片上加字
  bmp.Canvas.Font.Name := '宋体' ;
  bmp.Canvas.Font.Size := 30 ;
  bmp.Canvas.Font.Color:= clRed ;
  bmp.Canvas.TextOut(3,3,'LX6010D  '+formatdatetime('yyyymmddhhmmss',now)
      +'  速度:'+IntToStr(Speeddiff)+'  限速:'+IntToStr(SpeedLimit)+'  '+TakePlace);//违法信息  picName:=AppPath+'pic\'+formatdatetime('yyyymmdd',now);
  if not DirectoryExists(picName) then
      ForceDirectories(picName);
  picName:=AppPath+'pic\'+formatdatetime('yyyymmdd',now)+'\'
        +formatdatetime('yyyymmddhhmmss',now)
        +format('%3.3d',[SpeedLimit])+format('%3.3d',[speeddiff])+'.jpg';  MyJpeg.Assign(bmp);
  MyJpeg.SaveToFile(picName);
  img.Picture.LoadFromFile(picName);
  Application.ProcessMessages;
except
  sb1.Panels[0].Text:='图片错误！';
  Application.ProcessMessages;
end;
end;
        
end;现在我想实现在拍照的同时能实时的速度数据！！即实现 
if (str<>'') then
      begin
         Application.ProcessMessages;
         SpeedDisp1.Lines.Add(str);
      end;
      if (SpeedDisp1.Lines.Count>=200) then
        SpeedDisp1.Lines.Delete(0);
这段代码功能我现在的问题是如果超速了在拍摄照片的过程中有下一个速度来的话不能实时的显示出来
望大虾们指点任何解决啊？？？？？？？