Android与OBD口通讯单行接收数据

Question

我在 Android 中通过蓝牙使用消息聊天实现了这个应用程序。该应用程序有效，它连接到 obd 端口并与其交换消息，但问题是我收到多行数据，如下所示：

为什么obd端口的回复是这样的？我的传入数据流有问题吗？

这里有一些关于我回复的代码：

private class ConnectedThread extends Thread {
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        private final OutputStream mmOutStream;

        public ConnectedThread(BluetoothSocket socket) {
            Log.d(TAG, "create ConnectedThread: ");
            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            // Get the BluetoothSocket input and output streams
            try {
                tmpIn = socket.getInputStream();
                tmpOut = socket.getOutputStream();
            } catch (IOException e) {
                Log.e(TAG, "temp sockets not created", e);
            }

            mmInStream = tmpIn;
            mmOutStream = tmpOut;
            mState = STATE_CONNECTED;
        }

        public void run() {
            Log.i(TAG, "BEGIN mConnectedThread");
            byte[] buffer = new byte[1024];
            int bytes;

            // Keep listening to the InputStream while connected
            while (mState == STATE_CONNECTED) {
                try {
                    // Read from the InputStream
                    bytes = mmInStream.read(buffer);

                    // Send the obtained bytes to the UI Activity
                    mHandler.obtainMessage(Constants.MESSAGE_READ, bytes, -1, buffer)
                            .sendToTarget();
                } catch (IOException e) {
                    Log.e(TAG, "disconnected", e);
                    connectionLost();
                    break;
                }
            }
        }

        /**
         * Write to the connected OutStream.
         *
         * @param buffer The bytes to write
         */
        public void write(byte[] buffer) {
            try {
                mmOutStream.write(buffer);

                // Share the sent message back to the UI Activity
                mHandler.obtainMessage(Constants.MESSAGE_WRITE, -1, -1, buffer)
                        .sendToTarget();
            } catch (IOException e) {
                Log.e(TAG, "Exception during write", e);
            }
        }

        public void cancel() {
            try {
                mmSocket.close();
            } catch (IOException e) {
                Log.e(TAG, "close() of connect socket failed", e);
            }
        }
    }

以及管理与 obd 端口和其他事物的对话的处理程序：

 /**
     * The Handler that gets information back from the MyBluetoothService
     */
    private final Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            //FragmentActivity activity = getActivity();
            switch (msg.what) {
                case Constants.MESSAGE_STATE_CHANGE:
                    switch (msg.arg1) {
                        case MyBluetoothService.STATE_CONNECTED:
                            setStatus(getString(R.string.title_connected_to, mConnectedDeviceName));
                            mConversationArrayAdapter.clear();

                            /*String EchoOffCommand = "ATE0\r";
                            String LineFeedOff = "ATL0\r";
                            sendMessage(EchoOffCommand);
                            sendMessage(LineFeedOff);*/

                            break;
                        case MyBluetoothService.STATE_CONNECTING:
                            setStatus(R.string.title_connecting);
                            break;
                        case MyBluetoothService.STATE_LISTEN:
                        case MyBluetoothService.STATE_NONE:
                            setStatus(R.string.title_not_connected);
                            break;
                    }
                    break;
                case Constants.MESSAGE_WRITE:
                    byte[] writeBuf = (byte[]) msg.obj;
                    // construct a string from the buffer
                    String writeMessage = new String(writeBuf);
                    mConversationArrayAdapter.add("Me:  " + writeMessage);
                    break;
                case Constants.MESSAGE_READ:
                    byte[] readBuf = (byte[]) msg.obj;
                    // construct a string from the valid bytes in the buffer
                    String readMessage = new String(readBuf, 0, msg.arg1);
                    mConversationArrayAdapter.add(mConnectedDeviceName + ":  " + readMessage);
                    break;
                case Constants.MESSAGE_DEVICE_NAME:
                    // save the connected device's name
                    mConnectedDeviceName = msg.getData().getString(Constants.DEVICE_NAME);

                    Toast.makeText(getApplicationContext(), "Connected to "
                            + mConnectedDeviceName, Toast.LENGTH_SHORT).show();

                    break;
                case Constants.MESSAGE_TOAST:

                    Toast.makeText(getApplicationContext(), msg.getData().getString(Constants.TOAST),
                            Toast.LENGTH_SHORT).show();

                    break;
            }
        }
    };

Answer 1

OBD2 适配器内存不足。他们不一定会一次性传输整个答案，这打破了您的聊天程序的假设。

您的接收进程需要处理响应片段，缓冲所有片段，并且 – 一旦您像 \r\r> 那样解析响应终止符 – 重新组合片段并将其传递到上层。

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