代码运行时间长会出错，大家帮小弟我看看如何修改

代码运行时间长会出错，大家帮我看看怎么修改
procedure ControlCommReceiveData(Port:Integer; Buffer: Pointer; BufferLength: Integer);
var
  tem, ErrMsg:String;
  i : integer;
  CurAlleyNO : integer;
  CurAlley : TAlleyInfo;
  CardId, StdId : string;
  ComDataReault :integer;
begin
  StdId := '';
  try
  try
  if( not Assigned(zyCommData) ) then
  Exit;
  except
  WriteEvent(DataM.LocalDBCnct, '判断zyComm是否为空出错');
  end;

  if( ReceivingData = TRUE ) then
  begin
  ReceivingData := TRUE;
  WriteEvent(LocalDataM.LocalDBCnct, SysEvent_BusyRecvData, EventType_SysCmd);
  Exit;
  end;

  ReceivingData := TRUE;
  WriteEvent(DataM.LocalDBCnct, '接收数据开始');
  try
  tem := '';
  for i:=0 to BufferLength-1 do
  tem[i+1] := (Pchar(Buffer)+i)^; }
  except
  WriteEvent(DataM.LocalDBCnct, 'CCCCCCCCCCCCCCCC');
  end;


  try
  if(zyCommData.GetData(tem, BufferLength)=-1) then//在下面
  begin
  ReceivingData := FALSE;
  Exit;
  end;
  except
  WriteEvent(DataM.LocalDBCnct, 'DDDDDDDDDDDDDDDDDD');
  end;

  try
  tem := zyCommData.Data;
  except
  WriteEvent(DataM.LocalDBCnct, 'EEEEEEEEEEEEEEEEEEE');
  end;
  except
  WriteEvent(LocalDataM.LocalDBCnct, '1002');
  ReceivingData := FALSE;
  exit;
  end;
end;

function TSerialCommData.GetData(CommData:string; parDataLen:integer):Integer;
var
I : integer;
begin
Result := zyFailed;
try
  try
  if(CurLen=0) and (parDataLen>0) then
  begin
  CurLen := 0;
  Data := '';
  if( CommDataLenType = DLT_VarLen ) then
begin
DataLen := Integer(CommData[1]);
  if(( DataLen <> 15 ) and ( DataLen<>20 ) and ( DataLen<>45 )) and (CommData[1] <> #3)then
  begin
  Exit;
  end;
  end;
  end;
  except
  WriteEvent(LocalDataM.LocalDBCnct,'判断错误');
  end;

  for I:=1 to parDataLen Do
  begin
  try
  Data := Data + char(CommData[I]);
  except
  WriteEvent(LocalDataM.LocalDBCnct, '拼接数据出错AAAA');
  end;

  try
  Inc(CurLen);
  if( curLen = DataLen ) then
  begin
  Result := zySuccess;
  CurLen := 0;
  break;
  end;
  except
  WriteEvent(LocalDataM.LocalDBCnct,'拼接数据出错BBBB');
  end;
  end;
  except
  WriteEvent(LocalDataM.LocalDBCnct,'拼接数据出错');
  end;
end;

[解决办法]
先说清楚什么错误，错误定位在哪一行
[解决办法]
问题不明确，无法确定错误

[解决办法]
同1樓意見。
if( ReceivingData = TRUE ) then
begin
ReceivingData := TRUE;//這句代碼起碼是無用的。
WriteEvent(LocalDataM.LocalDBCnct, SysEvent_BusyRecvData, EventType_SysCmd);
Exit;
end;


[解决办法]