【发布时间】：2019-09-27 09:24:04
【问题描述】：
我们有一个供应商特定的血压设备，我们想通过 Android 方便地配置它 它是USB端口。 此外，我还为与 设备，据我所知，Android 和 WinUSB api（当然）有很多 相似之处，它应该工作得很好。我还可以在 Android 上打开设备 并获取端点（批量端点）。该设备支持中断和批量读/写端点。
我还可以通过 controlTransfer 成功地将命令写入设备，例如
private void tryGetDescriptor() {
byte[] buffer = new byte[18];
// https://www.beyondlogic.org/usbnutshell/usb6.shtml#SetupPacket standard device requests
int retVal = m_devCon.controlTransfer(0x80, 0x06, 0x0100, 0, buffer, 0x12, TIMEOUT);
if(retVal < 0) {
Debug("something failed");
} else {
Debug( "check buffer " + String.valueOf( retVal ) + " arr: " + Arrays.toString(buffer) );
}
}
或者我在 Delphi 中的参考代码所做的一个 controlTransfer：
private void startPeripheral() {
int retVal = m_devCon.controlTransfer(0x40, 2, 0, m_readPkgSize, null, 0, 0);
if(retVal < 0) {
Debug("StartPeripheral failed!");
} else {
Debug("Control Transfer returned " + String.valueOf(retVal));
}
}
我现在面临的问题是根据写入端点我可能会向设备发送命令 但我没有得到回报（设备至少应该回显命令）
这里是处理该问题的线程（我知道同步的东西实际上不是 Java，所以请 对我有耐心……）
private UsbDeviceConnection m_devCon;
private UsbEndpoint m_epRead;
private UsbEndpoint m_epWrite;
private String m_command = "";
private boolean terminated = false;
public void sigTerminate(){
terminated = true;
m_command = "";
}
public void init( UsbDeviceConnection devCon, UsbEndpoint readEP, UsbEndpoint writeEP ) {
this.m_devCon = devCon;
this.m_epRead = readEP;
this.m_epWrite = writeEP;
}
public void asyncSendCmd( String cmd ) {
Debug("AsyncSendCmd: " + cmd);
m_command = new String(cmd);
}
private void sendRec() {
Debug("Run thread");
byte[] buffer = new byte[m_readPkgSize];
try {
//while( req.queue( rBuf ) ) {
while (true) {
try {
while (m_command == "" && !terminated)
sleep(10);
Debug("Something found" + m_command);
} catch (InterruptedException f) {
Thread.currentThread().interrupt();
Debug("Thread interruped: " + f.getMessage());
}
String cpyCmd = new String(BR102_RESET );
m_command = "";
if (!terminated && isConnected()) {
// not threadsave but what shels
Debug("Writing command: " + cpyCmd);
byte[] writeBuf = cpyCmd.getBytes();
//int lenWrite = m_devCon.bulkTransfer(m_epWrite, writeBuf, writeBuf.length, TIMEOUT);
//if (lenWrite != writeBuf.length)
// throw new IOException("Write failed with len: " + String.valueOf(lenWrite));
// sleep(48);
UsbRequest wreq = new UsbRequest();
wreq.initialize( m_devCon, m_epWrite);
ByteBuffer wBuf = ByteBuffer.wrap(writeBuf);
wreq.queue( wBuf );
final UsbRequest responsew = m_devCon.requestWait( TIMEOUT );
if(responsew == null) {
Debug("no write response");
break;
}
int lenWrite = wBuf.position();
Debug("Wrote: " + String.valueOf(lenWrite));
wreq.close();
UsbRequest req = new UsbRequest();
req.initialize(m_devCon, m_epRead);
ByteBuffer rBuf = ByteBuffer.wrap( buffer );
req.queue( rBuf );
//int lenRead = m_devCon.bulkTransfer(m_epRead, buffer, m_readPkgSize, TIMEOUT);
final UsbRequest response = m_devCon.requestWait(TIMEOUT);
if(response == null) {
Debug("No Resonse");
break;
}
int lenRead = rBuf.position();
if (lenRead > 0) Debug("lenRead: " + String.valueOf(lenRead));
else Debug("lenRead: " + String.valueOf(lenRead));
req.close();
}
//rBuf.rewind();
//req.close();
}
} catch (Exception e) {
Debug("Error in usb read thread: " + e.toString());// e.getMessage());
}
}
@Override
public void run() {
sendRec();
}
}
正如大家所见，我尝试了很多东西。这是我想出的最复杂的一个。基本上 我的第一次尝试是或多或少的 bulkTransfers，它们的行为相同......
注意“Reset\n”命令可以发送2次，然后甚至写入失败...
为了完整起见，这里是 USB 初始化例程：
private void startUSB(UsbDevice device) throws IllegalArgumentException {
UsbManager usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
if(!usbManager.hasPermission( device )) {
usbManager.requestPermission( device, m_permissionIntent );
return;
}
try {
if( usbReader != null) {
Debug("WTF usbReader already started!!!!");
usbReader.sigTerminate();
usbReader.join();
usbReader = null;
}
// ########################################################
// #### we the permission -> get the interfaces and check for the endpoints
m_device = device;
int numInterfaces = m_device.getInterfaceCount();
if(numInterfaces > 0) {
Debug("Number of interfaces: " + String.valueOf(numInterfaces));
m_devIntf = m_device.getInterface(0);
Debug(String.valueOf(m_devIntf.getInterfaceProtocol()));
Debug("Number of endpoints: " + m_devIntf.getEndpointCount());
m_epRead = null;
m_epWrite = null;
for (int i = 0; i < m_devIntf.getEndpointCount(); i++) {
UsbEndpoint endPoint = m_devIntf.getEndpoint(i);
Debug(String.valueOf(i + 1) + ": Endpoint " + endPoint.toString());
if (endPoint.getDirection() == UsbConstants.USB_DIR_IN && endPoint.getType() == UsbConstants.USB_ENDPOINT_XFER_BULK) {
m_epRead = endPoint;
}
if (endPoint.getDirection() == UsbConstants.USB_DIR_OUT && endPoint.getType() == UsbConstants.USB_ENDPOINT_XFER_BULK) {
m_epWrite = endPoint;
}
}
if (m_epRead == null || m_epWrite == null)
throw new IllegalArgumentException("No bulk read or write endpoint found");
Debug("Got endpoints");
// ############################################################################
// okidoki we have endpoints and we have an interface -> open the device
m_devCon = usbManager.openDevice(m_device);
Debug("Got device");
if (m_devCon == null)
throw new IllegalArgumentException("No Deviceconnection?!");
if (!m_devCon.claimInterface(m_devIntf, false))
throw new IllegalArgumentException("Claim failed");
Debug("All fine - now we can start the conversation");
m_readPkgSize = m_epRead.getMaxPacketSize();
m_writePkgSize = m_epWrite.getMaxPacketSize();
tryGetDescriptor();
// ############################################################################
// ### init reading and wrinting
usbReader = new UsbReadThread();
usbReader.init( m_devCon, m_epRead, m_epWrite );
usbReader.start();
startPeripheral();
} else {
Debug("No interfaces");
}
} catch(Exception e)
{
Debug( "Device connection failed with " + e.getMessage() );
// release
closeUSB();
return;
}
}
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