HEM-7600T: works only when bluetoothctl is running

[shalak]

When I tried pairing and connecting to HEM-7600T, I kept getting the following error:

# python omblepy.py -d HEM-7600T --mac XX:XX:XX:XX:XX:XX --loggerDebug
2024-02-14 16:51:26,089 - omblepy - INFO - Attempt to import module for device hem-7600t
2024-02-14 16:51:26,134 - omblepy - INFO - Attempt connecting to XX:XX:XX:XX:XX:XX.
2024-02-14 16:51:32,465 - omblepy - INFO - unpair and disconnect
Traceback (most recent call last):
  File "/srv/services/omble/omblepy/omblepy.py", line 364, in main
    await bleClient.pair(protection_level = 2)
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/__init__.py", line 629, in pair
    return await self._backend.pair(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/backends/bluezdbus/client.py", line 473, in pair
    assert_reply(reply)
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/backends/bluezdbus/utils.py", line 22, in assert_reply
    raise BleakDBusError(reply.error_name, reply.body)
bleak.exc.BleakDBusError: [org.bluez.Error.AuthenticationFailed] Authentication Failed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/srv/services/omble/omblepy/omblepy.py", line 389, in <module>
    asyncio.run(main())
  File "/usr/lib/python3.11/asyncio/runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/base_events.py", line 653, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/srv/services/omble/omblepy/omblepy.py", line 387, in main
    await bleClient.disconnect()
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/__init__.py", line 614, in disconnect
    return await self._backend.disconnect()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/backends/bluezdbus/client.py", line 420, in disconnect
    assert self._bus is None
           ^^^^^^^^^^^^^^^^^
AssertionError

In the meantime, journalctl -u bluetooth.service showed:

lut 14 16:51:17 hostname bluetoothd[3979]: src/device.c:new_auth() No agent available for request type 2
lut 14 16:51:17 hostname bluetoothd[3979]: device_confirm_passkey: Operation not permitted

However, whenever I start bluetoothctl in other console windows (and keep it running), it does suceed to pair/sync, the user1.csv contains correct data and journalctl stays silent.

But still, it ends with an AssertionError:

# python omblepy.py -d HEM-7600T --mac XX:XX:XX:XX:XX:XX
2024-02-14 16:56:14,429 - omblepy - INFO - Attempt to import module for device hem-7600t
2024-02-14 16:56:14,468 - omblepy - INFO - Attempt connecting to XX:XX:XX:XX:XX:XX.
2024-02-14 16:56:21,527 - omblepy - INFO - communication started
2024-02-14 16:56:22,436 - omblepy - INFO - start reading data, this can take a while, use debug flag to see progress
2024-02-14 16:56:29,049 - omblepy - INFO - communication finished
2024-02-14 16:56:29,056 - omblepy - INFO - writing data to user1.csv
2024-02-14 16:56:29,062 - omblepy - INFO - unpair and disconnect
Traceback (most recent call last):
  File "/srv/services/omble/omblepy/omblepy.py", line 389, in <module>
    asyncio.run(main())
  File "/usr/lib/python3.11/asyncio/runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/base_events.py", line 653, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/srv/services/omble/omblepy/omblepy.py", line 387, in main
    await bleClient.disconnect()
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/__init__.py", line 614, in disconnect
    return await self._backend.disconnect()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/srv/services/omble/venv-omble/lib/python3.11/site-packages/bleak/backends/bluezdbus/client.py", line 420, in disconnect
    assert self._bus is None
           ^^^^^^^^^^^^^^^^^
AssertionError

I'm on Ubuntu 23.04 & bluetoothctl: 5.66, commit 1f43fef.

Is there anything I can do to fix this?

[userx14]

The first issue you see is likely connected to the bluetooth library used in the project. They also have an issue with the exact same problem: hbldh/bleak#1434 . Maybe the workaround presented in the thread also works in your case.

In the second case, you can get rid of this assertion error by commenting # this line:

omblepy/omblepy.py

Line 387 in 1f43fef

await bleClient.disconnect()

The bluetooth backend I'm using, the .unpair() in the line above should also disconnect the device. But that does not seem to work on windows, hence the extra disconnect statement. On linux this likely works as described and the second disconnect call leads to the error you are seeing.
You could also just ignore the error, this is last line before the program terminates anyway.

[tecbeat]

I think i have a similar error on my Mac.

2024-04-18 15:25:48,302 - omblepy - INFO - Attempt connecting to 73FDC143-7F01-56F1-CB71-A5DCDDAB08A2.
2024-04-18 15:25:52,009 - omblepy - INFO - unpair and disconnect
Traceback (most recent call last):
  File "/Users/xxx/tmp/omblepy/./omblepy.py", line 389, in <module>
    asyncio.run(main())
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 194, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/base_events.py", line 685, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/Users/xxx/tmp/omblepy/./omblepy.py", line 364, in main
    await bleClient.pair(protection_level = 2)
  File "/Users/xxx/tmp/omblepy/venv/lib/python3.12/site-packages/bleak/__init__.py", line 629, in pair
    return await self._backend.pair(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/xxx/tmp/omblepy/venv/lib/python3.12/site-packages/bleak/backends/corebluetooth/client.py", line 191, in pair
    raise NotImplementedError("Pairing is not available in Core Bluetooth.")
NotImplementedError: Pairing is not available in Core Bluetooth.

Versions:

Package                        Version
------------------------------ -------
bleak                          0.21.1
pip                            24.0
pyobjc-core                    9.2
pyobjc-framework-Cocoa         9.2
pyobjc-framework-CoreBluetooth 9.2
pyobjc-framework-libdispatch   9.2
terminaltables                 3.1.10

[userx14]

Hi @tecbeat ,

I'm not so confident that these problems are related.

The bluetooth library I use does not support pairing on mac, see:
https://bleak.readthedocs.io/en/latest/backends/macos.html#bleak.backends.corebluetooth.client.BleakClientCoreBluetooth.pair

Maybe it works if you just comment out this line:

omblepy/omblepy.py

Line 364 in 8297ce6

await bleClient.pair(protection_level = 2)

I did not have the chance to test with mac os so far.

Best,
Benjamin

[tecbeat]

Hi, yes it seems to be a different problem. I have tried to omit the line but unfortunately this does not work and throws the error below. I will just try it on a linux device. Thanks for the quick reply.

2024-04-18 16:08:05,073 - omblepy - INFO - Attempt connecting to 73FDC143-7F01-56F1-CB71-A5DCDDAB08A2.
2024-04-18 16:08:09,215 - omblepy - INFO - unpair and disconnect
Traceback (most recent call last):
  File "/Users/xxx/tmp/omblepy/./omblepy.py", line 389, in <module>
    asyncio.run(main())
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 194, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/base_events.py", line 685, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/Users/xxx/tmp/omblepy/./omblepy.py", line 373, in main
    await bluetoothTxRxObj.writeNewUnlockKey()
  File "/Users/xxx/tmp/omblepy/./omblepy.py", line 222, in writeNewUnlockKey
    raise ValueError(f"Could not enter key programming mode. Has the device been started in pairing mode? Got response: {deviceResponse}")
ValueError: Could not enter key programming mode. Has the device been started in pairing mode? Got response: bytearray(b'\x82\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')