Android的USB主機無法讀取和寫入數據Cp2102SerialDriver

我正在Android主機應用程序，我需要從所有連接的設備讀取數據。使用USB串行電纜「Cp2102SerialDriver」。Android的USB主機無法讀取和寫入數據Cp2102SerialDriver

這裏是我指

http://code.google.com/p/usb-serial-for-android/

我能夠成功地顯示與供應商和產品ID連接的設備的示例鏈路，這裏是示例代碼

/** Simple container for a UsbDevice and its driver. */ 
private static class DeviceEntry { 
    public UsbDevice device; 
    public UsbSerialDriver driver; 

    DeviceEntry(UsbDevice device, UsbSerialDriver driver) { 
     this.device = device; 
     this.driver = driver; 
    } 
} 

final List<DeviceEntry> result = new ArrayList<DeviceEntry>(); 
      for (final UsbDevice device : mUsbManager.getDeviceList() 
        .values()) { 

       final List<UsbSerialDriver> drivers = UsbSerialProber 
         .probeSingleDevice(mUsbManager, device); 

       Log.d(TAG, "Found usb device: " + device); 
       if (drivers.isEmpty()) { 
        Log.d(TAG, " - No UsbSerialDriver available."); 
        result.add(new DeviceEntry(device, null)); 
       } else { 
        for (UsbSerialDriver driver : drivers) { 
         Log.d(TAG, " + " + driver); 
         result.add(new DeviceEntry(device, driver)); 
        } 
       }

我指的是安卓主機教程

http://developer.android.com/guide/topics/connectivity/usb/host.html

與設備

mListView.setOnItemClickListener(new ListView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> parent, View view, 
       int position, long id) { 
      Log.d(TAG, "Pressed item " + position); 
      if (position >= mEntries.size()) { 
       Log.w(TAG, "Illegal position."); 
       return; 
      } 

      final DeviceEntry entry = mEntries.get(position); 


      if (entry.device != null) { 

       IntentFilter intentfilter = new IntentFilter(
         "com.android.example.USB_PERMISSION"); 
       DeviceListActivity.this.registerReceiver(
         mUsbReceiverPermission, intentfilter); 

       Toast.makeText(DeviceListActivity.this, 
         " Registered for broadcast reciever ", 
         Toast.LENGTH_SHORT).show(); 
       sendData(); 

      } 


     } 
    }); 


private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION"; 
private final BroadcastReceiver mUsbReceiverPermission = new BroadcastReceiver() { 

    public void onReceive(Context context, Intent intent) { 
     String action = intent.getAction(); 

     Toast.makeText(getApplicationContext(), action, Toast.LENGTH_SHORT) 
       .show(); 
     if (ACTION_USB_PERMISSION.equals(action)) { 
      synchronized (this) { 
       UsbDevice device = (UsbDevice) intent 
         .getParcelableExtra(UsbManager.EXTRA_DEVICE); 

       if (intent.getBooleanExtra(
       UsbManager.EXTRA_PERMISSION_GRANTED, false)) { 
       if (device != null) { 
        usbDeviceConnection = mUsbManager.openDevice(device); 
        cp2102SerialDriver = new Cp2102SerialDriver(device, 
          usbDeviceConnection); 
        try { 
         cp2102SerialDriver.open(); 

         Toast.makeText(getApplicationContext(), 
           "cp2102SerialDriver is open successfully", 
           Toast.LENGTH_SHORT).show(); 

        } catch (IOException e) { 
         e.printStackTrace(); 
        } 

       } 
       } else { 
       Log.d(TAG, "permission denied for device " + device); 

       } 
      } 
     } 
    } 
};

溝通要寫入數據，我使用此代碼

String data = etText.getText().toString() + "/n"; 

       bytes = data.getBytes(Charset.forName("UTF-8")); 
       try { 
        cp2102SerialDriver.write(bytes, 3000); 
       } catch (IOException e) { 
        // TODO Auto-generated catch block 
        e.printStackTrace(); 
       } 
      }

不過，雖然寫我得到異常。在此先感謝您的幫助。

來源

2014-02-28 u_pendra

那會是什麼例外？請編輯從logcat到你的文章的異常堆棧跟蹤，以便我們不必猜測它可能是什麼。 –

否克里斯，這是串行驅動程序異常拋出接口CommonUsbSerialDriver –

如果你需要幫助，你仍然需要發佈異常的日誌。 –

現在我自己做了這個例外，因爲我沒有檢查USB管理器是否有權限。點擊上面提到的代碼中的選定設備列表，我添加了兩行代碼。

if (!mUsbManager.hasPermission(entry.device)) { mUsbManager.requestPermission(entry.device,pendingIntent); }

來源

2014-03-01 06:46:14

Android的USB主機無法讀取和寫入數據Cp2102SerialDriver

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