我试图使用Android USB主机API来阅读我的USB游戏控制器的数据，一旦我得到这个工作，我将连接其他设备的测试。 我的游戏控制器使用OTG线连接到我的Android手机。 我现在能拿到设备，端点的信息，但我不知道如何读的原始数据并显示它。
有人可以帮帮我吗？ 一些示例代码将被理解的。
TextView countDisplay;
ArrayList<String> listItems = new ArrayList<String>();
ArrayAdapter<String> adapter;
String values = "";
UsbManager mManager;
UsbDevice device = null;
private byte[] bytes;
private static int TIMEOUT = 0;
private boolean forceClaim = true;
static PendingIntent mPermissionIntent;
UsbDeviceConnection connection = null;
UsbEndpoint InputEndpoint = null;
UsbEndpoint OutputEndpoint = null;
private Handler mHandler = new Handler();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mManager = (UsbManager) getSystemService(Context.USB_SERVICE);
mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(
"com.android.example.USB_PERMISSION"), 0);
IntentFilter filter = new IntentFilter();
filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
registerReceiver(mUsbReceiver, filter);
HashMap<String, UsbDevice> deviceList = mManager.getDeviceList();
values = values + "deviceListSize:" + deviceList.size() + ",tostring:"
+ deviceList.toString();
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
while (deviceIterator.hasNext()) {
device = deviceIterator.next();
values = values + ",device id:" + device.getDeviceId()
+ ",device name:" + device.getDeviceName();
values = values + ",Protocol:" + device.getDeviceProtocol()
+ ",ProductId:" + device.getProductId();
values = values + ",DeviceClass:" + device.getDeviceClass()
+ ",VendorId:" + device.getVendorId();
}
if (device != null) {
values = values + ",getInterfaceCount:"
+ device.getInterfaceCount();
UsbInterface intf = device.getInterface(0);
values = values + ",intf.getEndpointCount():"
+ intf.getEndpointCount();
UsbEndpoint endpoint1 = intf.getEndpoint(0);
UsbEndpoint endpoint2 = intf.getEndpoint(1);
mManager.requestPermission(device, mPermissionIntent);
if (mManager.hasPermission(device)) {
values = values + ",has permission over device!";
connection = mManager.openDevice(device);
if (connection == null) {
values = values + ",connection null";
} else {
values = values + ",getFileDescriptor:"
+ connection.getFileDescriptor();
if (endpoint1.getDirection() == UsbConstants.USB_DIR_IN) {
InputEndpoint = endpoint1;
} else {
OutputEndpoint = endpoint1;
}
if (endpoint2.getDirection() == UsbConstants.USB_DIR_IN) {
InputEndpoint = endpoint2;
} else {
OutputEndpoint = endpoint2;
}
}
if (InputEndpoint == null) {
countDisplay.setText(values + ",InputEndpoint is null");
}
if (OutputEndpoint == null) {
countDisplay.setText(values + ",OutputEndPoint is null");
}
connection.claimInterface(intf, forceClaim);
mHandler.postDelayed(runnable, 1);
} else {
values = values + ",Do not have permission over device!";
}
}
setContentView(R.layout.activity_main);
LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.activity_main, null);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
int counter = 1;
countDisplay = new TextView(this);
ll.addView(countDisplay);
countDisplay.setText(values + ",counter here");
final Button button = new Button(this);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (device != null && mManager.hasPermission(device)) {
values = values + ",device id:" + device.getDeviceId()
+ ",device name:" + device.getDeviceName();
values = values + ",Protocol:" + device.getDeviceProtocol()
+ ",ProductId:" + device.getProductId();
values = values + ",DeviceClass:" + device.getDeviceClass()
+ ",VendorId:" + device.getVendorId();
countDisplay.setText(values + ",okok");
} else {
if (device != null)
mManager.requestPermission(device, mPermissionIntent);
}
}
});
ll.addView(button);
setContentView(ll);
}
和可运行：
private Runnable runnable = new Runnable() {
public void run() {
if (connection != null) {
int count = connection.bulkTransfer(InputEndpoint, bytes,
bytes.length, TIMEOUT);
countDisplay.setText(values + ",bultTransferNo:" + count);
countDisplay.setText(values + "bulkValue:" + bytes);
} else {
countDisplay.setText(values + ",connection is null");
}
}
};
该程序作为下列USB主机功能的例子：
所有代码版权所有：
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
AdbDevice
package com.android.adb;
import android.hardware.usb.UsbConstants;
import android.hardware.usb.UsbDeviceConnection;
import android.hardware.usb.UsbEndpoint;
import android.hardware.usb.UsbInterface;
import android.hardware.usb.UsbRequest;
import android.util.SparseArray;
import java.util.LinkedList;
/* This class represents a USB device that supports the adb protocol. */
public class AdbDevice {
private final AdbTestActivity mActivity;
private final UsbDeviceConnection mDeviceConnection;
private final UsbEndpoint mEndpointOut;
private final UsbEndpoint mEndpointIn;
private String mSerial;
// pool of requests for the OUT endpoint
private final LinkedList<UsbRequest> mOutRequestPool = new LinkedList<UsbRequest>();
// pool of requests for the IN endpoint
private final LinkedList<UsbRequest> mInRequestPool = new LinkedList<UsbRequest>();
// list of currently opened sockets
private final SparseArray<AdbSocket> mSockets = new SparseArray<AdbSocket>();
private int mNextSocketId = 1;
private final WaiterThread mWaiterThread = new WaiterThread();
public AdbDevice(AdbTestActivity activity, UsbDeviceConnection connection,
UsbInterface intf) {
mActivity = activity;
mDeviceConnection = connection;
mSerial = connection.getSerial();
UsbEndpoint epOut = null;
UsbEndpoint epIn = null;
// look for our bulk endpoints
for (int i = 0; i < intf.getEndpointCount(); i++) {
UsbEndpoint ep = intf.getEndpoint(i);
if (ep.getType() == UsbConstants.USB_ENDPOINT_XFER_BULK) {
if (ep.getDirection() == UsbConstants.USB_DIR_OUT) {
epOut = ep;
} else {
epIn = ep;
}
}
}
if (epOut == null || epIn == null) {
throw new IllegalArgumentException("not all endpoints found");
}
mEndpointOut = epOut;
mEndpointIn = epIn;
}
// return device serial number
public String getSerial() {
return mSerial;
}
// get an OUT request from our pool
public UsbRequest getOutRequest() {
synchronized(mOutRequestPool) {
if (mOutRequestPool.isEmpty()) {
UsbRequest request = new UsbRequest();
request.initialize(mDeviceConnection, mEndpointOut);
return request;
} else {
return mOutRequestPool.removeFirst();
}
}
}
// return an OUT request to the pool
public void releaseOutRequest(UsbRequest request) {
synchronized (mOutRequestPool) {
mOutRequestPool.add(request);
}
}
// get an IN request from the pool
public UsbRequest getInRequest() {
synchronized(mInRequestPool) {
if (mInRequestPool.isEmpty()) {
UsbRequest request = new UsbRequest();
request.initialize(mDeviceConnection, mEndpointIn);
return request;
} else {
return mInRequestPool.removeFirst();
}
}
}
public void start() {
mWaiterThread.start();
connect();
}
public AdbSocket openSocket(String destination) {
AdbSocket socket;
synchronized (mSockets) {
int id = mNextSocketId++;
socket = new AdbSocket(this, id);
mSockets.put(id, socket);
}
if (socket.open(destination)) {
return socket;
} else {
return null;
}
}
private AdbSocket getSocket(int id) {
synchronized (mSockets) {
return mSockets.get(id);
}
}
public void socketClosed(AdbSocket socket) {
synchronized (mSockets) {
mSockets.remove(socket.getId());
}
}
// send a connect command
private void connect() {
AdbMessage message = new AdbMessage();
message.set(AdbMessage.A_CNXN, AdbMessage.A_VERSION, AdbMessage.MAX_PAYLOAD, "host::\0");
message.write(this);
}
// handle connect response
private void handleConnect(AdbMessage message) {
if (message.getDataString().startsWith("device:")) {
log("connected");
mActivity.deviceOnline(this);
}
}
public void stop() {
synchronized (mWaiterThread) {
mWaiterThread.mStop = true;
}
}
// dispatch a message from the device
void dispatchMessage(AdbMessage message) {
int command = message.getCommand();
switch (command) {
case AdbMessage.A_SYNC:
log("got A_SYNC");
break;
case AdbMessage.A_CNXN:
handleConnect(message);
break;
case AdbMessage.A_OPEN:
case AdbMessage.A_OKAY:
case AdbMessage.A_CLSE:
case AdbMessage.A_WRTE:
AdbSocket socket = getSocket(message.getArg1());
if (socket == null) {
log("ERROR socket not found");
} else {
socket.handleMessage(message);
}
break;
}
}
void log(String s) {
mActivity.log(s);
}
private class WaiterThread extends Thread {
public boolean mStop;
public void run() {
// start out with a command read
AdbMessage currentCommand = new AdbMessage();
AdbMessage currentData = null;
// FIXME error checking
currentCommand.readCommand(getInRequest());
while (true) {
synchronized (this) {
if (mStop) {
return;
}
}
UsbRequest request = mDeviceConnection.requestWait();
if (request == null) {
break;
}
AdbMessage message = (AdbMessage)request.getClientData();
request.setClientData(null);
AdbMessage messageToDispatch = null;
if (message == currentCommand) {
int dataLength = message.getDataLength();
// read data if length > 0
if (dataLength > 0) {
message.readData(getInRequest(), dataLength);
currentData = message;
} else {
messageToDispatch = message;
}
currentCommand = null;
} else if (message == currentData) {
messageToDispatch = message;
currentData = null;
}
if (messageToDispatch != null) {
// queue another read first
currentCommand = new AdbMessage();
currentCommand.readCommand(getInRequest());
// then dispatch the current message
dispatchMessage(messageToDispatch);
}
// put request back into the appropriate pool
if (request.getEndpoint() == mEndpointOut) {
releaseOutRequest(request);
} else {
synchronized (mInRequestPool) {
mInRequestPool.add(request);
}
}
}
}
}
}
AdbMessage
package com.android.adb;
import android.hardware.usb.UsbRequest;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
/* This class encapsulates and adb command packet */
public class AdbMessage {
// command names
public static final int A_SYNC = 0x434e5953;
public static final int A_CNXN = 0x4e584e43;
public static final int A_OPEN = 0x4e45504f;
public static final int A_OKAY = 0x59414b4f;
public static final int A_CLSE = 0x45534c43;
public static final int A_WRTE = 0x45545257;
// ADB protocol version
public static final int A_VERSION = 0x01000000;
public static final int MAX_PAYLOAD = 4096;
private final ByteBuffer mMessageBuffer;
private final ByteBuffer mDataBuffer;
public AdbMessage() {
mMessageBuffer = ByteBuffer.allocate(24);
mDataBuffer = ByteBuffer.allocate(MAX_PAYLOAD);
mMessageBuffer.order(ByteOrder.LITTLE_ENDIAN);
mDataBuffer.order(ByteOrder.LITTLE_ENDIAN);
}
// sets the fields in the command header
public void set(int command, int arg0, int arg1, byte[] data) {
mMessageBuffer.putInt(0, command);
mMessageBuffer.putInt(4, arg0);
mMessageBuffer.putInt(8, arg1);
mMessageBuffer.putInt(12, (data == null ? 0 : data.length));
mMessageBuffer.putInt(16, (data == null ? 0 : checksum(data)));
mMessageBuffer.putInt(20, command ^ 0xFFFFFFFF);
if (data != null) {
mDataBuffer.put(data, 0, data.length);
}
}
public void set(int command, int arg0, int arg1) {
set(command, arg0, arg1, (byte[])null);
}
public void set(int command, int arg0, int arg1, String data) {
// add trailing zero
data += "\0";
set(command, arg0, arg1, data.getBytes());
}
// returns the command's message ID
public int getCommand() {
return mMessageBuffer.getInt(0);
}
// returns command's first argument
public int getArg0() {
return mMessageBuffer.getInt(4);
}
// returns command's second argument
public int getArg1() {
return mMessageBuffer.getInt(8);
}
// returns command's data buffer
public ByteBuffer getData() {
return mDataBuffer;
}
// returns command's data length
public int getDataLength() {
return mMessageBuffer.getInt(12);
}
// returns command's data as a string
public String getDataString() {
int length = getDataLength();
if (length == 0) return null;
// trim trailing zero
return new String(mDataBuffer.array(), 0, length - 1);
}
public boolean write(AdbDevice device) {
synchronized (device) {
UsbRequest request = device.getOutRequest();
request.setClientData(this);
if (request.queue(mMessageBuffer, 24)) {
int length = getDataLength();
if (length > 0) {
request = device.getOutRequest();
request.setClientData(this);
if (request.queue(mDataBuffer, length)) {
return true;
} else {
device.releaseOutRequest(request);
return false;
}
}
return true;
} else {
device.releaseOutRequest(request);
return false;
}
}
}
public boolean readCommand(UsbRequest request) {
request.setClientData(this);
return request.queue(mMessageBuffer, 24);
}
public boolean readData(UsbRequest request, int length) {
request.setClientData(this);
return request.queue(mDataBuffer, length);
}
private static String extractString(ByteBuffer buffer, int offset, int length) {
byte[] bytes = new byte[length];
for (int i = 0; i < length; i++) {
bytes[i] = buffer.get(offset++);
}
return new String(bytes);
}
@Override
public String toString() {
String commandName = extractString(mMessageBuffer, 0, 4);
int dataLength = getDataLength();
String result = "Adb Message: " + commandName + " arg0: " + getArg0() +
" arg1: " + getArg1() + " dataLength: " + dataLength;
if (dataLength > 0) {
result += (" data: \"" + getDataString() + "\"");
}
return result;
}
private static int checksum(byte[] data) {
int result = 0;
for (int i = 0; i < data.length; i++) {
int x = data[i];
// dang, no unsigned ints in java
if (x < 0) x += 256;
result += x;
}
return result;
}
}
AdbSocket
package com.android.adb;
/* This class represents an adb socket. adb supports multiple independent
* socket connections to a single device. Typically a socket is created
* for each adb command that is executed.
*/
public class AdbSocket {
private final AdbDevice mDevice;
private final int mId;
private int mPeerId;
public AdbSocket(AdbDevice device, int id) {
mDevice = device;
mId = id;
}
public int getId() {
return mId;
}
public boolean open(String destination) {
AdbMessage message = new AdbMessage();
message.set(AdbMessage.A_OPEN, mId, 0, destination);
if (! message.write(mDevice)) {
return false;
}
synchronized (this) {
try {
wait();
} catch (InterruptedException e) {
return false;
}
}
return true;
}
public void handleMessage(AdbMessage message) {
switch (message.getCommand()) {
case AdbMessage.A_OKAY:
mPeerId = message.getArg0();
synchronized (this) {
notify();
}
break;
case AdbMessage.A_WRTE:
mDevice.log(message.getDataString());
sendReady();
break;
}
}
private void sendReady() {
AdbMessage message = new AdbMessage();
message.set(AdbMessage.A_OKAY, mId, mPeerId);
message.write(mDevice);
}
}
有关USB的更多信息和连接您可能会发现下面的文章有帮助。
http://android.serverbox.ch/?p=549
最后一段解释了一些你可能会面临的问题。 他们提供的例子也可以告诉你如何去读取数据，以及如何你将不得不格式化的消息。
看起来你面对两个问题。 一个设置你的代码来读取信息，这Puspendu的回答aludes，而且可能是第二个问题“如何”沟通，你需要什么样的信息发送到建立连接，握手，并确定好东西，即数据你要。
Puspendu已经显示出的读取和写入的设备的一个例子。 但是我可以想象这取决于你连接的设备上，握手和消息结构会发生变化，因此，你必须看看那些部分组成（怕我不知道任何其他的例子）。
文章来源: Using Android USB Host API to read my USB game controller/Or other USB device data
