/**
* Searches for the device and opens it if successful
*
* @return true, if connection was successful
*/
public boolean FindDevice() {
_usbManager = (UsbManager) _context.getSystemService(Context.USB_SERVICE);
HashMap<String, UsbDevice> deviceList = _usbManager.getDeviceList();
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
_usbDevice = null;
// Iterate all the available devices and find ours.
while (deviceIterator.hasNext()) {
UsbDevice device = deviceIterator.next();
if (device.getProductId() == _productId && device.getVendorId() == _vendorId) {
_usbDevice = device;
_deviceName = _usbDevice.getDeviceName();
}
}
if (_usbDevice == null) {
Log("Cannot find the device. Did you forgot to plug it?");
Log(String.format("\t I search for VendorId: %s and ProductId: %s", _vendorId, _productId));
_connectionHandler.onDeviceNotFound();
return false;
}
// Create and intent and request a permission.
PendingIntent mPermissionIntent =
PendingIntent.getBroadcast(_context, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
_context.registerReceiver(mUsbReceiver, filter);
_usbManager.requestPermission(_usbDevice, mPermissionIntent);
Log("Found the device and requested permission.");
return true;
}
public void run() {
Log("USB Thread started");
UsbEndpoint readEp = null;
UsbDeviceConnection usbConnection = null;
UsbInterface Intf = null;
UsbInterface Intf0 = null;
UsbEndpoint readEp0 = null;
UsbEndpoint writeEp0 = null;
byte[] readbuffer = new byte[64];
Log("Entering Read loop");
interfaceclaimed = false;
while (!_shouldstop) {
if (_usbDevice == null) {
Log("No device. Open device and Recheck in 1 sec...");
interfaceclaimed = false;
FindDevice();
Sleep(10000);
continue;
}
if (!interfaceclaimed) {
Log("Read loop Aquiring Interface 0 and Endpoint 1");
Intf = _usbDevice.getInterface(1);
readEp = Intf.getEndpoint(0);
Log("Read loop Aquiring Interface 0 and Endpoint 0");
Intf0 = _usbDevice.getInterface(0);
readEp0 = Intf0.getEndpoint(0);
writeEp0 = Intf0.getEndpoint(1);
if (!_usbManager.getDeviceList().containsKey(_deviceName)) {
Log("Failed to connect to the device. Retrying to acquire it.");
FindDevice();
if (!_usbManager.getDeviceList().containsKey(_deviceName)) {
Log("No device. Recheking in 10 sec...");
_connectionHandler.onDeviceNotFound();
Sleep(10000);
continue;
}
}
try {
usbConnection = _usbManager.openDevice(_usbDevice);
if (usbConnection == null) {
Log(
"Cannot start reader because the user didn't gave me permissions or the device is not present. Retrying in 2 sec...");
_connectionHandler.onUSBPermissionError();
Sleep(2000);
continue;
}
Log("USB loop claiming interface");
// Claim and lock the interface in the android system.
if (usbConnection.claimInterface(Intf, true)
&& usbConnection.claimInterface(Intf0, true)) {
Log("USB loop Interface claimed successful");
interfaceclaimed = true;
_connectionHandler.onUSBDeviceClaimed();
}
} catch (SecurityException e) {
Log(
"Cannot start reader because the user didn't gave me permissions. Retrying in 2 sec...");
interfaceclaimed = false;
Sleep(2000);
continue;
}
}
/*
int filed = readConnection.getFileDescriptor();
int epaddress = readEp.getAddress();
TeensyDeviceUsbNativeHelper nativehelper = new TeensyDeviceUsbNativeHelper(filed,64,epaddress);
nativehelper.beginUrbReadLoop();
byte[] buffer2 = new byte[64];
nativehelper.readUrb(1000, buffer2);
//_receivedQueue.add(buffer2);
Log(String.format("Message received of lengths %s and content: %s", 64, composeString(buffer2)));
*/
synchronized (_writelocker) {
// Queue a USBRequest to USB if any data is in queue
if (_writeQueue.size() > 0) {
byte[] writebuffer = _writeQueue.poll();
Log(String.format("Writing to USB: %s", CAN_Frame.bytesToHexString(writebuffer)));
// Log("USB loop sending bulk write request");
if (usbConnection.bulkTransfer(writeEp0, writebuffer, 64, 100) < 0) {
// failed to transfer
Log("USB loop sending bulk write request FAILED");
} // else Log("USB loop sending bulk write request SUCCEEDED");
}
}
synchronized (_locker) {
// Log("Read loop Waiting for requst to complete");
if (usbConnection.bulkTransfer(readEp0, readbuffer, 64, 100) >= 0) {
byte[] readbuffertrimmed = new byte[readbuffer[0]];
System.arraycopy(readbuffer, 0, readbuffertrimmed, 0, readbuffer[0]);
_receivedQueue.add(readbuffertrimmed);
Log(String.format("Message received: %s", CAN_Frame.bytesToHexString(readbuffer)));
_connectionHandler.onUSBRecieve();
}
}
// Sleep for 10 ms to pause, so other thread can write data or anything.
// As both read and write data methods lock each other - they cannot be run in parallel.
// Looks like Android is not so smart in planning the threads, so we need to give it a
// small time
// to switch the thread context.
// Sleep(10);
}
if (usbConnection != null) {
usbConnection.releaseInterface(Intf);
usbConnection.releaseInterface(Intf0);
interfaceclaimed = false;
usbConnection.close();
_connectionHandler.onUsbStopped();
Log("USB Thread ENDED!");
}
}