The document summarizes the USB Host API in Android. It discusses connecting to and communicating with USB devices from an Android application using the USB Host API. Key points include using intents to detect attached devices, requesting permission to access devices, claiming interfaces and endpoints, and performing control and bulk transfers using UsbDeviceConnection and UsbRequest. Sample code is provided to illustrate requesting permission, bulk transfers, and asynchronous I/O using callbacks.

1. USB Host API
P-touch RL RL-700S

2. • (@zaki50)
•
• Android
( StickyShortcut)
A3

3. USB Host

4. USB Host
Android 3.1 Platform highlights
• Honeycomb 3.1
• OS
(HID Mass
Storage)
•
(
)

5. USB Host API
• USB
API
• OS
• USB
•

7. • : USB
UsbDeviceConnection
• : UsbDeviceConnection

8. • Intent
(IntentFilter )
•
(listDevices )

9. IntentFilter
AndroidManifest.xml
<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" />
res/device_filter.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<usb-device vendor-id="1234" product-id="5678" />
</resources>

10. listDevice
•
USB Device
•
• BroadcastReceiver /

11. private static final String ACTION_USB_PERMISSION = "hogehoge.USB_PERMISSION";
• IntentFilter private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
final UsbDevice device = (UsbDevice) intent
• BroadcastReceiver .getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (!intent.getBooleanExtra(UsbManager
.EXTRA_PERMISSION_GRANTED, false)) {
Log.i(TAG, "USB Permission denied");
PrintActivity.this.setResult(Activity.RESULT_CANCELED);
PrintActivity.this.finish();
return;
}
//
requestPermission }
}
}
};
//
registerReceiver(mUsbReceiver, new IntentFilter(ACTION_USB_PERMISSION));
final PendingIntent pi = PendingIntent.getBroadcast(this, 0, new Intent(
ACTION_USB_PERMISSION), 0);
mManager.requestPermission(device, pi);

12. USB
• vendor ID product ID
• Interface
• interface Endpoint
• Endpoint ( / )

13. Endpoint
• Control
↓
• Interrupt http://ja.wikipedia.org/wiki/
Universal_Serial_Bus
• Bulk
• Isochronous

14. • claimInterface
• Endpoint
• controlTransfer/bulkTransfer
• UsbRequest

15. UsbEndpoint endpoint = ...; // Endpoint
byte[] buffer = ...;
int timeoutMillis = 5000;
final int sent = conn.bulkTransfer(endpoint, buffer,
buffer.length, timeoutMillis);
•
• buffer offset

16. UsbDeviceConnection conn = ...;
UsbEndpoint in = ...;
ByteBuffer recvBuffer = ByteBuffer.allocate(in.getMaxPacketSize());
UsbRequest recvReq = new UsbRequest();
recvReq.initialize(conn, in); // Endpoint
while (true) {
recvReq.queue(recvBuffer, recvBuffer.remaining()); //
UsbRequest request = conn.requestWait(); //
if (request != recvReq) {
//
break;
}
// recvBuffer
}

17. • 1 UsbConnection
•

18. • bulkTransfer
• UsbRequest
• type Control bulkTransfer
controlTransfer

19. • @touchRL
twitter RFID
• Windows
• Mac

21. @touchRL

22. • DevGuide (USB - Host)
http://developer.android.com/guide/topics/usb/host.html
•
http://developer.android.com/resources/samples/USB/
index.html
• (github)
• RL-700S http://goo.gl/fFA93
• RL-700S http://goo.gl/rV7TZ