Question

我将Arduino Nano设置为TCP服务器。然后我写了一个Android应用程序打开套接字并发送数据，但它无法从服务器接收答案。 TCP服务器正在从Android应用程序接收消息，但有时会收到更多空消息：

Android日志：

05-27 04:08:04.673 7571-7571/com.livingroom.stefan.livinglight D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
05-27 04:08:04.768 7571-7571/com.livingroom.stefan.livinglight D/LivingLight: onBtnClick(): gathering data from Buttons
05-27 04:08:04.768 7571-7571/com.livingroom.stefan.livinglight D/LivingLight: onBtnClick(): data gathered: 00000000
05-27 04:08:04.843 7571-9973/com.livingroom.stefan.livinglight D/LivingLight: startCom(): open socket(192.168.188.25,23598)
05-27 04:08:04.843 7571-9973/com.livingroom.stefan.livinglight D/LivingLight: startCom(): sending data to device
05-27 04:08:04.848 7571-9973/com.livingroom.stefan.livinglight D/LivingLight: startCom(): data sent to device (00000000)
05-27 04:08:04.848 7571-9973/com.livingroom.stefan.livinglight D/LivingLight: startCom(): socket closed

从Arduino登录：

ESP8266: init()
ESP8266: connected to wifi
ESP8266: TCP Server started
AT+CIFSR

+CIFSR:STAIP,"192.168.188.25"
+CIFSR:STAMAC,"18:fe:34:a5:22:bb"

OK
got message:,9:00000000
0,CLOSED

set outputs: 00000000
got message:
got message:
got message:
got message:
got message:

要检查我的服务器或Android应用中是否存在此问题，我尝试从另外两台设备向我的Arduino发送数据。我的Raspberry Pi上的C代码和一个名为＆＃34; SocketTest3＆＃34;工作得很好。两者都正确地发送数据并从TCP服务器接收确认。这就是为什么我猜这个问题出现在我的Android代码中。

奇怪的是，只有来自Android设备的消息后面有0,CLOSED。

我在这里找到了一些建议，比如刷新PrintWriter或等待BufferedReader.ready()。但他们都没有找到解决方案。方法PrintWriter.checkError()是错误的。

我的Arduino代码是：

void loop() {
  int client = esp8266.getId();
  if (client >= 0) {
    String msg = esp8266.readString();
    // receive data from serial buffer
    esp8266.sendData(client, "#\r\n");
    // acknowledge received data
    debug("got message:");
    debug(msg);
    // eg.:  ,9:01101001
    debug("\n");
    int start = msg.indexOf(':')+1;
    // gets index of : char
    if((msg.charAt(start)-48)>=0) {
      // checks if buffer contains data
      debug("set outputs: ");
      for(int i=0; i<N_LED; i++) {
        // for each LED (starts with PIN 2)
        digitalWrite((i+2),(msg.charAt(start+i)-48));
        debug(digitalRead(i+2));
        EEPROM.write(i,digitalRead(i+2));
      }
      debug("\n");
    }
    esp8266.closeConnection(client);
  }
} //end loop

字符串准备txData：

public void onBtnClick() {
    txData = "";
    if(tbAllOff.isChecked()) {
        Log.d(TAG, "onBtnClick, allOff");
        txData = "00000000";
    } else if(tbAllOn.isChecked()) {
        Log.d(TAG, "onBtnclick, allOn");
        txData = "11111111";
    } else {
        Log.d(TAG, "onBtnClick, gathering data from Buttons");
        for (int i=0; i<tbList.length; i++) {
            txData += (tbList[i].isChecked())?1:0;
        }
        Log.d(TAG, "onBtnClick, data gathered: " + txData);
    }


    if (Build.VERSION.SDK_INT>= Build.VERSION_CODES.HONEYCOMB)
        new Client().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
    else
        new Client().execute();
    txt1.setText(rxData);
}

我的Android应用程序的套接字部分是：

private class Client extends AsyncTask<String, Void, Void> {
  protected Void doInBackground(String[] params) {
    try {
      Log.d(TAG,"AsyncTask.doInBackground(): send data: "+ txData);
      rxData = startCom();
    } catch(IOException e) {
      e.printStackTrace();
      rxData = "IOException: " + e;
      Log.e(TAG,rxData);
    }
    return null;
  }

  private String startCom() throws IOException {
    ipAddress = "192.168.188.25";
    portNumber = 23598;
    Socket socket = new Socket(ipAddress, portNumber);
    Log.d(TAG,"startCom(): open socket(" + ipAddress + "," + portNumber + ")");
    BufferedReader input = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    PrintWriter output = new PrintWriter(socket.getOutputStream(),true);
    Log.d(TAG,"startCom(): sending data to device");
    output.println(txData);
    output.close();
    Log.d(TAG,"startCom(): data sent to device (" + txData + ")");
    String in = "#";
    if(input.ready()) {
      in = input.readLine();
      Log.d(TAG, "startCom(): data received: " + in);
    }
    socket.close();
    Log.d(TAG,"startCom(): socket closed");
    return in;
  }
}

Android和Arduino之间的wifi通信中的Ghostdata

0 个答案: