//-------------------------------------------------------------------
void __fastcall TForm1::btnConnectClick(TObject *Sender)
{
 Edit1->Text="";
 Edit2->Text="";     COMMTIMEOUTS TimeOut;
        TimeOut.ReadIntervalTimeout = 0;
        TimeOut.ReadTotalTimeoutMultiplier = 0;
        TimeOut.ReadTotalTimeoutConstant = 500;  //(總讀取 time out 時間 = 0.5 秒)
        TimeOut.WriteTotalTimeoutMultiplier = 0;
        TimeOut.WriteTotalTimeoutConstant = 500; //(總寫入 time out 時間 = 0.5 秒)        if (BuildCommDCB("9600,n,8,1",&dcb))
                  //(每秒傳輸率,n,8bit,一個停止位元)
        {                    lbBuildCommDCB->Caption="BuildCommDCB 成功";            }        else
        {                    lbBuildCommDCB->Caption="BuildCommDCB 失敗";            }     handle=CreateFile("Com1",GENERIC_READ|GENERIC_WRITE,0,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
                //(檔案名,可讀可寫,不共享,不保密,開啟舊檔,檔案屬性)        if (SetCommState(handle,&dcb))
                  //(存放執行CreatFile函數後所傳回的HANDLE代碼,指向 DCB 資料結構的位址)            lbSetCommState->Caption="SetCommState 成功";        else            lbSetCommState->Caption="SetCommState 失敗";        if (SetupComm(handle,1024,1024))
                //(同上,輸入資料佇列大小,輸出資料佇列大小)            lbSetupComm->Caption="SetupComm 成功";        else            lbSetupComm->Caption="SetupComm 失敗";        if (SetCommTimeouts(handle,&TimeOut))            lbSetCommTimeouts->Caption="SetCommTimeouts 成功";        else
    
        lbSetCommTimeouts->Caption="SetCommTimeouts 失敗";
        
}
//---------------------------------------------------------------------------    void __fastcall TForm1::btnTransmissionClick(TObject *Sender)
{
 char lpBuf;
 char WriteBuffer;
 char *ptr;
 DWORD dwWrite;
 DWORD dwRead;     ptr=Edit1->Text.c_str();
 WriteBuffer=*ptr;
 WriteFile(handle,&WriteBuffer,1,&dwWrite,0);
 ReadFile(handle, &lpBuf, 1, &dwRead, NULL);
 
   if (dwRead == 0)          {
        lbStatus->Caption="沒有回應 !!";
      }       else          {
        Edit2->Text=Edit1->Text+lpBuf;
      }
}
//---------------------------------------------------------------------------
void __fastcall TForm1::btnDisconnectClick(TObject *Sender)
{
        Close();        
}
//---------------------------------------------------------------------------    

引言: Hi! Edit2->Text=Edit1->Text+lpBuf; 改 Edit2->Text=Edit2->Text+lpBuf; 但你的程式,按鍵一次只送一個字元. 感謝DavidLo大大回應,經過大大的指正小弟發現小弟的程式只能傳一個字元,但是為什麼現在要傳4個字元(如圖)才會出現第一個字元呢?傳一個就接收不到?? 還有若小弟想做成可一次傳送好幾個字元,該怎麼修改呢?感謝大大指教^^

發表人 - iimumi 於 2005/12/01 11:59:58 發表人 - iimumi 於 2005/12/01 12:15:30 發表人 - iimumi 於 2005/12/01 12:47:52 發表人 - iimumi 於 2005/12/01 12:55:24

引言: 1.加Sleep(10)於Write and Read之間,10 is 10ms. 2.WriteFile(handle,&WriteBuffer,1,&dwWrite,0); 第3個參數是umber of bytes to write你設為1. 感謝大大回覆,小弟改了之後問題依然存在,請問是小弟改錯了嗎?

  char lpBuf;
 char WriteBuffer;
 char *ptr;
 DWORD dwWrite;
 DWORD dwRead;     ptr=Edit1->Text.c_str();
 WriteBuffer=*ptr;
 WriteFile(handle,&WriteBuffer,5,&dwWrite,0);
 Sleep(10);
 ReadFile(handle, &lpBuf, 1, &dwRead, NULL);

引言: 同writeFile ReadFile(handle, &lpBuf, 1, &dwRead, NULL); 第3個參數是umber of bytes to read你設為1,只讀1byte. 抱歉大大我有測試過writefile跟readfile都設為5但還是不行耶?

引言: 設為5時,dwWrite and dwRead為多少? 跟原先一樣，設為0和NULL

引言: 我指的是ReadFile執行完時,dwRead是多少!其代表實際得到Byte數. 5是想要Byte數.WriteFile同理. DavidLo大大很抱歉,之前沒搞清楚你的意思^^" dwRead和dwWrite都是5,

void __fastcall TForm1::btnTransmissionClick(TObject *Sender)
{
 ptr=Edit1->Text.c_str();
 WriteBuffer=*ptr;
 WriteFile(handle,&WriteBuffer,5,&dwWrite,0);
 Sleep(10);
 ReadFile(handle, &lpBuf, 5, &dwRead, NULL);       if (dwRead == 0)//預設是0,故若傳回0,代表沒回應          {
        lbStatus->Caption="沒有回應 !!";
      }       else          {
        Edit2->Text=Edit2->Text+lpBuf;
      }    }
//--------------------------------------------------------------------
void __fastcall TForm1::btnReadClick(TObject *Sender)
{
AnsiString a,b;
a=dwWrite;
b=dwRead;
lbdwWrite->Caption="dwWrite:"+a;
lbdwRead->Caption="dwRead:"+b;
//--------------------------------------------------------------------

  char lpBuf;//宣告一個字元
  char WriteBuffer;//宣告一個字元
  char *ptr;//宣告一個指標
  ...
  ptr=Edit1->Text.c_str();//字串丟給指標???
  WriteBuffer=*ptr;
  WriteFile(handle,&WriteBuffer,5,&dwWrite,0);

  char txbuf[255],rxbuf[255];
  ...
  strcpy(txbuf,Edit1->Text.c_str());
  WriteFile(handle,&txbuf,5,&dwWrite,0);
  Sleep(10);
  ReadFile(handle,&rxbuf,5,&dwRead, NULL);
  Edit2->Text=rxbuf;

strcpy(txBuf,Edit1->Text.c_str());    //(目的字串,無結尾的來源字串)
 WriteFile(handle,&txBuf,255,&dwWrite,0);
 Sleep(10);
 ReadFile(handle, &rxBuf, 255, &dwRead, NULL);       if (dwRead == 0)//預設是0,故若傳回0,代表沒回應          {
        lbStatus->Caption="沒有回應 !!";
      }       else          {
        Edit2->Text=rxBuf;
      }