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POEstablish communication between Android host and USB Device
 

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    <p>i'm trying to implement a bidirectional communication between an android host and a USB device, of course i'm using the USB Host API provided by Google. The USB Device contains a firmware that echoes any character it receives. The user just inserts a character in a EditText and press a Button to send the character. Here is the code</p> <pre><code>public void sendData(View v){ final String character = request.getText().toString() + "\n\r"; log.setText(log.getText() + "\n" + "Sending..."); if(character != null){ Thread t = new Thread(new Runnable() { @Override public void run() { byte[] array = character.getBytes(); Log.d("USB", "Sending Data..."); mDeviceConnection.bulkTransfer(mEndpointOut, array, array.length, 100); ByteBuffer output_buffer = ByteBuffer.allocate(array.length); Log.d("USB", "Creating Buffer"); UsbRequest req = new UsbRequest(); req.initialize(mDeviceConnection, mEndpointIn); req.queue(output_buffer, array.length); if(mDeviceConnection.requestWait() == req){ Log.d("USB", output_buffer.getChar(0) + ""); Message m = new Message(); m.obj = output_buffer.array(); handler.sendMessage(m); output_buffer.clear(); } else{ Log.d("USB", "No USBRequest received"); } } }); t.start(); } } </code></pre> <p>The variable request is the EditText, log is a reference to a TextView so i can show some debbug information. First i send the character using the bulkTransfer method, then i use USBRequest to queue a request to read data on the in endpoint, aparently it send the character correctly, but whe i show the received character, it show some weird symbols, like chinese characters or a rhombus with a question symbol inside (almost always this is the response). I Want to know if the code i use for this communication is correct, and if it is, then why am i receiving that weird characters?</p> <p>Thank you so much for you help</p> <p>PD: Sorry for my english.</p>
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