onRunError:

[BlueSky15171]

Run ending due to exception: Queueing USB request failed
java.io.IOException: Queueing USB request failed
at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:200)
at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:169)
at com.hoho.android.usbserial.util.SerialInputOutputManager.step(SerialInputOutputManager.java:225)
at com.hoho.android.usbserial.util.SerialInputOutputManager.run(SerialInputOutputManager.java:203)
 at java.lang.Thread.run(Thread.java:764)

I am tring to communicate between android app and android app. I confirmed that I received the message and also replied to it. May I ask how should I solve this problem?

Thanks!

[kai-morich]

please provide more context, e.g. did you disconnect the device, did it happen immediately after connection or hours later, ...

[BlueSky15171]

--------- beginning of main
--------- beginning of system
2023-07-11 09:43:33.414  1403-4345  ActivityTrigger         system_process                       E  activityResumeTrigger: not whiteListedcom.exp.pc/com.exp.pc.MainActivity/1
2023-07-11 09:43:33.437  1403-2073  ActivityTrigger         system_process                       E  activityResumeTrigger: not whiteListedcom.exp.pc/com.exp.pc.MainActivity/1
2023-07-11 09:43:33.487  6549-6549  ProlificSerialDriver    com.exp.pc                      D  usbVersion=110, deviceVersion=400, deviceClass=0, packetSize=64 => deviceType=DEVICE_TYPE_HX
2023-07-11 09:43:33.487  6549-6597  SerialInpu...putManager com.exp.pc                      W  Run ending due to exception: Queueing USB request failed
                                                                                                    java.io.IOException: Queueing USB request failed
                                                                                                       at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:200)
                                                                                                       at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:169)
                                                                                                       at com.hoho.android.usbserial.util.SerialInputOutputManager.step(SerialInputOutputManager.java:225)
                                                                                                       at com.hoho.android.usbserial.util.SerialInputOutputManager.run(SerialInputOutputManager.java:203)
                                                                                                       at java.lang.Thread.run(Thread.java:764)
2023-07-11 09:43:33.489  6549-6597  SerialListener          com.exp.pc                      E  onRunError: 
                                                                                                    java.io.IOException: Queueing USB request failed
                                                                                                       at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:200)
                                                                                                       at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:169)
                                                                                                       at com.hoho.android.usbserial.util.SerialInputOutputManager.step(SerialInputOutputManager.java:225)
                                                                                                       at com.hoho.android.usbserial.util.SerialInputOutputManager.run(SerialInputOutputManager.java:203)
                                                                                                       at java.lang.Thread.run(Thread.java:764)
2023-07-11 09:43:33.490  6549-6597  SerialInpu...putManager com.exp.pc                      I  Stopped
2023-07-11 09:43:33.492  6549-6549  UsbRequestJNI           com.exp.pc                      D  init
2023-07-11 09:43:33.496  6549-6605  SerialInpu...putManager com.exp.pc                      I  Running ...

@kai-morich I start to connect in Activity.onResume and exchange messages between Android and Android after connection. Strangely, even if there is a connection loss, I can still exchange messages.

[kai-morich]

if you can still exchange messages, you might have opened a new connection that killed the previous?

[BlueSky15171]

I'll try to disconnect before connecting.

[BlueSky15171]

I disconnected before connecting, it seems like there was no error reported。 @kai-morich Thanks!

[Jai-GAY]

@BlueSky15171

I disconnected before connecting,

I think I got a similar problem. can you share what disconnect here referring to? It happens during resource closing for my case.

D close E Error Reading: Attempt to invoke virtual method 'int android.hardware.usb.UsbDeviceConnection.controlTransfer(int, int, int, int, byte[], int, int)' on a null object reference Assuming inaccessible USB device. Closing connection. java.lang.NullPointerException: Attempt to invoke virtual method 'int android.hardware.usb.UsbDeviceConnection.controlTransfer(int, int, int, int, byte[], int, int)' on a null object reference at com.hoho.android.usbserial.driver.CommonUsbSerialPort.testConnection(CommonUsbSerialPort.java:162) at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:195) at com.hoho.android.usbserial.driver.CommonUsbSerialPort.read(CommonUsbSerialPort.java:169) at org.droidplanner.services.android.impl.communication.connection.usb.UsbHohoConnection.readDataBlock(UsbHohoConnection.java:221) at org.droidplanner.services.android.impl.communication.connection.usb.UsbConnection.readDataBlock(UsbConnection.java:107) at org.droidplanner.services.android.impl.core.MAVLink.connection.MavLinkConnection$2.run(MavLinkConnection.java:146) at java.lang.Thread.run(Thread.java:1012) I Exiting manager thread. E Error Sending: Error writing 14 bytes at offset 0 of total 14 java.io.IOException: Error writing 14 bytes at offset 0 of total 14 at com.hoho.android.usbserial.driver.CommonUsbSerialPort.write(CommonUsbSerialPort.java:265) at org.droidplanner.services.android.impl.communication.connection.usb.UsbHohoConnection.sendBuffer(UsbHohoConnection.java:238) at org.droidplanner.services.android.impl.communication.connection.usb.UsbConnection.sendBuffer(UsbConnection.java:116) at org.droidplanner.services.android.impl.core.MAVLink.connection.MavLinkConnection$3.run(MavLinkConnection.java:195) at java.lang.Thread.run(Thread.java:1012)

[kai-morich]

you very likely closed the connection in a different thread, so read aborts with NPE as on mConnection is null, I will improve the exception message, but when your are in closing phase you better ignore all exceptions.

[BlueSky15171]

@Jai-GAY I have repeated the connection.

[kai-morich]

exception improved with 399d3c9c2f241212ce9213c076b5426bd34a81af and 35fdeb1e1355cdddc3b208949a9598cd6f17da8f

[BlueSky15171]

@Jai-GAY Thanks