我遇到了一个奇怪的问题。我编写了一个应用程序,它将与arduino建立蓝牙SPP链接。 Arduino上的蓝牙设备配置为9600波特。我可以从arduino接收数据,但似乎我收到一些值为0或高峰值的故障。这非常烦人,因为我确实需要图形部分的精确值,我知道arduino发送好的数据,因为我记录它在文件中发送的内容。
我正在寻找修复或理解为什么会发生这种情况,而不是创建一个平均值或类似的东西来制作“补丁”。
感谢您的帮助。
这是一张可以解释我的问题的图片,arduino数据范围大约是101到103:
Screenshot http://s9.postimage.org/n1td3bb4f/Screenshot_2013_03_20_22_30_15_1.png
以下是我创建连接和接收数据的代码:
private class ConnectedThread extends Thread {
private final DataInputStream mmInStream;
private final DataOutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = new DataInputStream(tmpIn);
mmOutStream = new DataOutputStream(tmpOut);
}
public void run() {
byte[] buffer = new byte[1024]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer); // Get number of bytes and message in "buffer"
hBluetooth.obtainMessage(RECEIVE_MESSAGE, bytes, -1, buffer).sendToTarget(); // Send to message queue Handler
} catch (IOException e) {
break;
}
}
}
private void connectDevice() {
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
try {
btSocket = createBluetoothSocket(device);
} catch (IOException e) {
errorExit("Fatal Error", "In onResume() and socket create failed: " + e.getMessage() + ".");
}
mBluetoothAdapter.cancelDiscovery();
// Establish the connection. This will block until it connects.
Log.d(TAG, "...Connecting...");
try {
btSocket.connect();
Log.d(TAG, "....Connection ok...");
// Create a data stream so we can talk to server.
Log.d(TAG, "...Create Socket...");
mConnectedThread = new ConnectedThread(btSocket);
mConnectedThread.start();
mActionBar.setSubtitle("Connecté");
//If fail, we disconnect or display an error warning regarding the situation
} catch (IOException e) {
try {
btSocket.close();
mActionBar.setSubtitle("Deconnecté");
} catch (IOException e2) {
errorExit("Fatal Error", "In onResume() and unable to close socket during connection failure" + e2.getMessage() + ".");
}
}
return;
}
最后是处理程序:
hBluetooth = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case RECEIVE_MESSAGE: // If we receive a message
byte[] readBuf = (byte[]) msg.obj;
String stringIncome = new String(readBuf, 0, msg.arg1); // Create string from byte array
stringBuilder.append(stringIncome);
int endOfLineIndex = stringBuilder.indexOf("\r\n"); // Determine the end-of-line
if (endOfLineIndex > 0) { // If we are at the end-of-line we parsed all the data that was sent
rmsgBluetooth = stringBuilder.substring(0, endOfLineIndex); // The string is extracted in a string object rmsgBluetooth
stringBuilder.delete(0, stringBuilder.length());
if(btSocket != null && btSocket.isConnected()){
//Here we send the value of the string to a txtbox
txtArduino.setText("Arduino: " + rmsgBluetooth);
if(rmsgBluetooth.matches("-?\\d+(\\.\\d+)?")) {
try{
sensorReading = Float.parseFloat(rmsgBluetooth);
}catch(NumberFormatException e){
}
}
答案 0 :(得分:0)
我认为你的错误最有可能在解析字符串时出现。请仔细调试行
if(rmsgBluetooth.matches("-?\\d+(\\.\\d+)?")) {
try{
sensorReading = Float.parseFloat(rmsgBluetooth);
}catch(NumberFormatException e){
}
}