Unstable auto detect for Humanware Brailliant and APH Mantis Q40 braille displays

[LeonarddeR]

Steps to reproduce:

1. Pair a Mantis Q40 over Bluetooth
2. Start NVDA with braille auto detection enabled.

Actual behavior:

NVDA sometimes fails detecting the display, because it tries the HID prottocol driver first. This driver reports as available but is not supported by the display. Interesting enough, as soon as you select the HID driver manually, NVDA connects to the display but the displays stays empty. When you open the display dialog again, nothing is selected and the HID driver disappeared.
Note that sometimes, NVDA manages to connect to the display with the Brailliant driver, but behavior is pretty instable on my system.

Expected behavior:

Direct connection using the Brailliant driver when using auto detect.

System configuration

NVDA installed/portable/running from source:

Installed

NVDA version:

2021.3

Windows version:

Windows 11 22000.348

Other questions

Does the issue still occur after restarting your computer?

Yes

Have you tried any other versions of NVDA? If so, please report their behaviors.

Same behavior as current Alpha.

If NVDA add-ons are disabled, is your problem still occurring?

Yes

Does the issue still occur after you run the COM Registration Fixing Tool in NVDA's tools menu?

Yes

[LeonarddeR]

note, issues with the Brailliant were reported by @dkager. They have the same firmware under the hood.

[dkager]

Thanks for reporting this. I can confirm the problem also occurs when you select Bluetooth as the port, rathern than Auto. USB works as usual. Might the Chameleon 20 also be affected?

[LeonarddeR]

Might the Chameleon 20 also be affected?

Likely, isn't that just a rebranded Brailliant?

[feerrenrut]

@LeonarddeR and @dkager could you please test and confirm this is fixed in the RC for 2021.3.1 https://www.nvaccess.org/post/nvda-2021-3-1rc1/

[LeonarddeR]

Yes, this works fine for me.

[dkager]

Not for me unfortunately (Brailliant BI 40X). Here is the log of me trying a couple of times, with various errors:

INFO - braille.BrailleHandler.setDisplayByName (20:14:33.330) - braille._BgThread (6540):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - brailleDisplayDrivers.hid.BrailleDisplayDriver.__init__ (20:14:33.330) - braille._BgThread (6540):
Found display with 40 cells connected via hid (\\?\hid#{00001124-0000-1000-8000-00805f9b34fb}_vid&00021d6b_pid&0246&col02#8&f2c30de&0&0001#{4d1e55b2-f16f-11cf-88cb-001111000030})
INFO - braille.BrailleHandler.setDisplayByName (20:14:33.346) - braille._BgThread (6540):
Loaded braille display driver hid, current display has 40 cells.
ERROR - unhandled exception (20:14:39.662) - braille._BgThread (6540):
Traceback (most recent call last):
  File "_ctypes/callbacks.c", line 232, in 'calling callback function'
  File "hwIo\base.pyc", line 144, in _ioDone
OSError: [WinError 1167] The device is not connected.
ERROR - braille.executor (20:14:52.897) - braille._BgThread (6540):
Error displaying cells. Disabling display
Traceback (most recent call last):
  File "braille.pyc", line 2233, in executor
  File "brailleDisplayDrivers\hid.pyc", line 196, in display
  File "hwIo\base.pyc", line 111, in write
OSError: [WinError 1167] The device is not connected.
ERROR - braille.BrailleHandler.handleDisplayUnavailable (20:14:52.897) - braille._BgThread (6540):
Braille display unavailable. Disabling
Traceback (most recent call last):
  File "braille.pyc", line 2233, in executor
  File "brailleDisplayDrivers\hid.pyc", line 196, in display
  File "hwIo\base.pyc", line 111, in write
OSError: [WinError 1167] The device is not connected.
INFO - braille.BrailleHandler.setDisplayByName (20:14:52.913) - braille._BgThread (6540):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - braille.BrailleHandler.setDisplayByName (20:14:54.350) - braille._BgThread (6540):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - brailleDisplayDrivers.hid.BrailleDisplayDriver.__init__ (20:14:54.350) - braille._BgThread (6540):
Found display with 40 cells connected via hid (\\?\hid#{00001124-0000-1000-8000-00805f9b34fb}_vid&00021d6b_pid&0246&col02#8&f2c30de&0&0001#{4d1e55b2-f16f-11cf-88cb-001111000030})
INFO - braille.BrailleHandler.setDisplayByName (20:14:54.350) - braille._BgThread (6540):
Loaded braille display driver hid, current display has 40 cells.
INFO - brailleDisplayDrivers.brailliantB.BrailleDisplayDriver.__init__ (20:15:05.021) - MainThread (2152):
Found display with 40 cells connected via hid (\\?\hid#{00001124-0000-1000-8000-00805f9b34fb}_vid&00021d6b_pid&0246&col01#8&f2c30de&0&0000#{4d1e55b2-f16f-11cf-88cb-001111000030})
INFO - braille.BrailleHandler.setDisplayByName (20:15:05.021) - MainThread (2152):
Loaded braille display driver brailliantB, current display has 40 cells.
ERROR - braille.executor (20:15:10.641) - braille._BgThread (6540):
Error displaying cells. Disabling display
Traceback (most recent call last):
  File "braille.pyc", line 2233, in executor
  File "brailleDisplayDrivers\brailliantB.pyc", line 240, in display
  File "hwIo\hid.pyc", line 301, in setOutputReport
OSError: [WinError 121] The semaphore timeout period has expired.
ERROR - braille.BrailleHandler.handleDisplayUnavailable (20:15:10.641) - braille._BgThread (6540):
Braille display unavailable. Disabling
Traceback (most recent call last):
  File "braille.pyc", line 2233, in executor
  File "brailleDisplayDrivers\brailliantB.pyc", line 240, in display
  File "hwIo\hid.pyc", line 301, in setOutputReport
OSError: [WinError 121] The semaphore timeout period has expired.
INFO - braille.BrailleHandler.setDisplayByName (20:15:15.511) - MainThread (2152):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - braille.BrailleHandler.setDisplayByName (20:15:15.647) - braille._BgThread (6540):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - braille.BrailleHandler.setDisplayByName (20:15:17.110) - braille._BgThread (6540):
Loaded braille display driver noBraille, current display has 0 cells.
INFO - brailleDisplayDrivers.hid.BrailleDisplayDriver.__init__ (20:15:17.110) - braille._BgThread (6540):
Found display with 40 cells connected via hid (\\?\hid#{00001124-0000-1000-8000-00805f9b34fb}_vid&00021d6b_pid&0246&col02#8&f2c30de&0&0001#{4d1e55b2-f16f-11cf-88cb-001111000030})
INFO - braille.BrailleHandler.setDisplayByName (20:15:17.118) - braille._BgThread (6540):
Loaded braille display driver hid, current display has 40 cells.
ERROR - stderr (20:15:17.119) - braille._BgThread (6540):
Exception in thread braille._BgThread:
Traceback (most recent call last):
  File "threading.pyc", line 926, in _bootstrap_inner
  File "threading.pyc", line 870, in run
  File "braille.pyc", line 2257, in func
OSError: exception: privileged instruction
INFO - braille.BrailleHandler.setDisplayByName (20:15:41.976) - MainThread (2152):
Loaded braille display driver noBraille, current display has 0 cells.

[feerrenrut]

@dkager I'm looking into this today, could you attach Debug level logs with the hwIO category enabled (via advanced settings panel).

Please do this with 2021.3.1rc1 and 2021.2. Having both logs will let me compare where things deviate from the expected path, and to confirm that this set of actions works correctly on 2021.2.

We are eager to get this release out in the next few days, hopefully we can address this before then.