如何从连接到Android设备的OTG USB接收原始数据

Question

我需要通过OTG线缆从接收器接收原始数据（可能是以二进制形式，特别是间隔，可能每5秒一次）。

我需要知道这是否可以在Android核心类或任何外部API / SDK的帮助下完成

注意：

1. 我有一对发射器和接收器。
2. 电池插入发射器，每隔5秒就会自动将数据传输到接收器。
3. 我已经从Google Play商店免费安装了OTG UART Hyperterminal，当我打开端口并进入主屏幕时，我注意到我每隔5秒收到一次十六进制数据。所以发射器和接收器工作正常。

以下是我的代码的一部分：

• 清单文件：

  <activity android:name="com.hoho.android.usbserial.examples.DeviceListActivity" android:label="@string/app_name" android:theme="@android:style/Theme.Black.NoTitleBar.Fullscreen">
    <intent-filter>
      <action android:name="android.intent.action.MAIN" />
      <category android:name="android.intent.category.DEFAULT" />
      <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
    <intent-filter>
      <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
    </intent-filter>
    <meta-data android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" android:resource="@xml/device_filter" />
  </activity>
  

• 在/ res / xml

下

• device_filter

我从代码中收到了这些详细信息。

<usb-device
    vendor-id="1105"
    product-id="5798"
    class="2"
    subclass="0"
    protocol="0"
/>

源代码：

import android.hardware.usb.UsbConstants;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.Iterator;
import android.hardware.usb.UsbDevice;
import android.hardware.usb.UsbDeviceConnection;
import android.hardware.usb.UsbEndpoint;
import android.hardware.usb.UsbInterface;
import android.hardware.usb.UsbManager;
import android.hardware.usb.UsbRequest;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.PendingIntent;
import android.app.ProgressDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.util.Log;
import android.view.Menu;
import android.view.TextureView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class Read_USB_Host_Receiver extends Activity {
  Button btnDeviceList;
  TextView txtResult;
  int iBulk=0;
  UsbManager usbManager;
  UsbDeviceConnection conn;
  BroadcastReceiver mUsbReceiver;
  PendingIntent mPermissionIntent;
  UsbDevice dev;

  private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";

  public void run(UsbDevice sDevice) {
    UsbDevice dev = sDevice;
    txtResult.setText("1");
    if (dev == null)
      return;
    txtResult.setText("2");
    mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
    IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
    registerReceiver(mUsbReceiver, filter);
    txtResult.setText("3");
    if(usbManager.hasPermission(dev)) {
      Log.d("USB", " Permission OK");
    } else {
      txtResult.setText("4");
      Log.d("USB", " Permission faild");
      usbManager.requestPermission(dev, mPermissionIntent);
      if(usbManager.hasPermission(dev)) {
        txtResult.setText("5");
        Log.d("USB", "Now is Permission OK");
      }
    }
    conn = usbManager.openDevice(dev);
    Log.i("Interface Count: "+conn,""+dev.getInterfaceCount());
    Log.i("Using ",""+ String.format("%04X:%04X", sDevice.getVendorId(),sDevice.getProductId()));
    txtResult.setText("6");
    new AsynReadUCBHostEndPoint().execute();
  }

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_read__usb__host__receiver);
    txtResult = (TextView)findViewById(R.id.textView1);
    usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
    mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
    IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
    registerReceiver(mUsbReceiver, filter);
    HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
    Log.i("deviceList size: ", ""+deviceList.size());
    Toast.makeText(Read_USB_Host_Receiver.this, ""+deviceList.size(), Toast.LENGTH_LONG).show();
    Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
    while(deviceIterator.hasNext()) {
      UsbDevice dd = deviceIterator.next();
      dev = dd;
      if(usbManager.hasPermission(dev)) {
        Log.d("USB", " Permission OK");
      } else {
        Log.d("USB", " Permission faild");
        usbManager.requestPermission(dev, mPermissionIntent);
        if(usbManager.hasPermission(dev)) {
          Log.d("USB", "Now is Permission OK");
        }
      }
    }
    btnDeviceList = (Button)findViewById(R.id.btnDeviceList);
    btnDeviceList.setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        // TODO Auto-generated method stub
        HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
        Log.i("deviceList size: ", ""+deviceList.size());
        Toast.makeText(Read_USB_Host_Receiver.this, ""+deviceList.size(), Toast.LENGTH_LONG).show();
        Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
        while(deviceIterator.hasNext()) {
          UsbDevice dd = deviceIterator.next();
          dev = dd;
          if (dd.getVendorId()==1105) {
            run(dd);
          }
        }
      }
    });

    mUsbReceiver = new BroadcastReceiver() {
      @Override
      public void onReceive(Context arg0, Intent intent) {
        // TODO Auto-generated method stub
        String action = intent.getAction();
        if (ACTION_USB_PERMISSION.equals(action)) {
          synchronized (this) {
            UsbDevice device = (UsbDevice)intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
            Log.i("HELLO", "BYE");
            if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
              if(device != null) {
                //call method to set up device communication
                Log.i("HELLO1", "BYE1");
              }
            } else {
              //  Log.d(TAG, "permission denied for device " + device);
            }
          }
        }
      }
    };
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_read__usb__host__receiver, menu);
    return true;
  }

  public void readUSBHostData() { }

  class AsynReadUCBHostEndPoint extends AsyncTask<Void,Integer,String> {
    ProgressDialog dialog;
    String response, result;
    @Override
    protected void onPreExecute() {
      // TODO Auto-generated method stub
      txtResult.setText("7");
      super.onPreExecute();
      dialog=new ProgressDialog(Read_USB_Host_Receiver.this);
      dialog.setMessage("Reading endpoint...");
      dialog.setCanceledOnTouchOutside(false);
      dialog.show();
    }

    @Override
    protected String doInBackground(Void... params) {
      // TODO Auto-generated method stub
      try {
        for (int j=0; j < dev.getInterfaceCount(); j++) {
          UsbInterface intf = dev.getInterface(j);
          UsbEndpoint endpoint = null;
          for (int i = 0; i < intf.getEndpointCount(); i++) {
            if (intf.getEndpoint(i).getDirection() == UsbConstants.USB_DIR_IN) {
              endpoint = intf.getEndpoint(i);
              break;
            }
          }
          if(endpoint != null) {
            if(usbManager.hasPermission(dev)) {
              Log.d("USB", " Permission OK");
            } else {
              Log.d("USB", " Permission faild");
              usbManager.requestPermission(dev, mPermissionIntent);
              if(usbManager.hasPermission(dev)) {
                Log.d("USB", "Now is Permission OK");
              }
            }
            conn = usbManager.openDevice(dev);
            conn.releaseInterface(intf);
            byte[] buffer = new byte[64];
            if (conn!=null && conn.claimInterface(intf, true)) {
              int retVal = conn.bulkTransfer(endpoint, buffer, 64, 5000);
              Log.i("return of bluk:", "" + retVal);
              while(retVal == 0) {
                retVal = conn.bulkTransfer(endpoint, buffer, 64, 200);
                Log.i("return of bluk in while loop:", "" + retVal);
              }
            }
          }
        }
      } catch (Exception e) {
        // TODO: handle exception
      }
      return result;
    }

    @Override
    protected void onProgressUpdate(Integer... values) {
      // TODO Auto-generated method stub
      super.onProgressUpdate(values);
    }

    @Override
    protected void onPostExecute(String result) {
      // TODO Auto-generated method stub
      super.onPostExecute(result);
      dialog.dismiss();
      txtResult.setText(result);
    }
  }

  public void GetData(UsbDevice dev) {
    for (int j=0; j < dev.getInterfaceCount(); j++) {
      UsbInterface intf = dev.getInterface(j);
      UsbEndpoint endpoint = null;
      for (int i = 0; i < intf.getEndpointCount(); i++) {
        if (intf.getEndpoint(i).getDirection() == UsbConstants.USB_DIR_IN) {
          endpoint = intf.getEndpoint(i);
          break;
        }
      }
      if(endpoint != null) {
        conn = usbManager.openDevice(dev);
        UsbRequest request = new UsbRequest(); // create an URB
        if (conn!=null) {
          boolean initilzed = request.initialize(conn, endpoint);
          if (!initilzed) {
            Log.e("USB CONNECTION FAILED", "Request initialization failed for reading");
            return;
          }
          while (true) {
            int bufferMaxLength = endpoint.getMaxPacketSize();
            ByteBuffer buffer = ByteBuffer.allocate(bufferMaxLength);
            if (request.queue(buffer, bufferMaxLength) == true) {
              if (conn.requestWait() == request) {
                String result = new String(buffer.array());
                Log.i("GELEN DATA : ", result);
              }
            }
          }
        }
      }
    }
  }
}