aiobmsble assertion error

[GoodLug]

I am trying to run the standalone aiobmsble.exe script, but it always crashes after seeing the battery. The error is "AssertionError" which google rather unhelpfully says shouldn't be in a production environment. I'm running python 3.13 on Win 10 and this is what I get (MAC redacted):

Microsoft Windows [Version 10.0.19045.6332]
(c) Microsoft Corporation. All rights reserved.

C:\Users\User\AppData\Local\Programs\Python\Python313\Scripts>aiobmsble.exe
INFO: starting scan...
INFO: 1 BT devices in range.
INFO: ------------------------------------------------------------------------
BT device 'ECO-WORTHY 0B_E241' (MAC address)
AdvertisementData(local_name='ECO-WORTHY 0B_E241',
manufacturer_data={57570: b'Zu2\x15'},
service_uuids=['0000fff0-0000-1000-8000-00805f9b34fb'],
rssi=-50)
INFO: Found matching BMS type: ECO-WORTHY BW02
INFO: Updating BMS data...
Traceback (most recent call last):
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble_main_.py", line 58, in detect_bms
data: BMSsample = await bms.async_update()
^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble\basebms.py", line 405, in async_update
await self._connect()
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble\basebms.py", line 275, in _connect
await self.client.disconnect() # ensure no stale connection exists
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\site-packages\bleak_init.py", line 588, in disconnect
await self._backend.disconnect()
File "C:\Program Files\Python312\Lib\site-packages\bleak\backends\winrt\client.py", line 468, in disconnect
assert self.services
^^^^^^^^^^^^^
AssertionError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "", line 198, in run_module_as_main
File "", line 88, in run_code
File "C:\Users\User\AppData\Local\Programs\Python\Python313\Scripts\aiobmsble.exe_main.py", line 7, in
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble_main.py", line 95, in main
asyncio.run(detect_bms())
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 194, in run
return runner.run(main)
^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 118, in run
return self.loop.run_until_complete(task)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\base_events.py", line 687, in run_until_complete
return future.result()
^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble_main.py", line 63, in detect_bms
await bms.disconnect()
File "C:\Program Files\Python312\Lib\site-packages\aiobmsble\basebms.py", line 381, in disconnect
await self.client.disconnect()
File "C:\Program Files\Python312\Lib\site-packages\bleak_init.py", line 588, in disconnect
await self._backend.disconnect()
File "C:\Program Files\Python312\Lib\site-packages\bleak\backends\winrt\client.py", line 468, in disconnect
assert self.services
^^^^^^^^^^^^^
AssertionError

C:\Users\User\AppData\Local\Programs\Python\Python313\Scripts>

Any suggestions as to how I can fix this?

Thanks in advance.

[GoodLug]

Looking more closely at the error, I see that although I recently upgraded to python 3.13, and ran aiobmsble.eve from the python 3,13 scripts folder, as 3.13 is the minimum requirement for aiobmsble, the traceback shows it is still using 3.12... Upgrade hell!

Edit: I have now got a clean python 3.13 installation (3,12 removed entirely), but I still get the same AssertionError.

[patman15]

This is an issue with the Windows version of the Bleak library, see hbldh/bleak#1859.
For the moment you can just comment out the line

File "C:\Program Files\Python312\Lib\site-packages\aiobmsble\basebms.py", line 275, in _connect
await self.client.disconnect() # ensure no stale connection exists

How is this related to an integration issue or did you go for the wrong repo?

[GoodLug]

Thanks for your prompt and helpful reply.

I know have a clean python 3.13 installation, and will try to comment out the relevant line in that.

I think I got the right (latest) repo, and was trying to run it from the command line ie standalone outside Home Assistant, by running aiobmsble.exe in the python scripts folder.

I will report back once I have commented out the basebms.py line.

[GoodLug]

Bingo, it worked! I had to comment out the whole try/except block starting at line 338 (in Notepad++). I can now see the battery data values, and they are credible.

I expect I can work it out from your code, but can you give me a pointer as to how you extract the human readable values from the raw code. From what I can see, using things like ble-serial and a ble to COM port bridge, the BMS sends out long hex strings which contain the data. Or maybe you use characteristic UUIDs? I would be very interested in reading some of the other settings, because Eco-Worthy are not above programming in less than ideal values.

[patman15]

how you extract the human readable values from the raw code.

Why don't you just use the integration in Home Assistant? It does all of that for you.

[GoodLug]

I'm doing this for different setting, a boat. I suppose I could rename Home Assistant Boat Assistant, but it is one hell of huge non-Windows installation (my laptop runs Windows 10) just to achieve one aim.

The particular values I am interested in are the charging voltage cut offs, and the over current protection. The actual values can be somewhat different to those on a data sheet.

[patman15]

Well, if you just want to use the library, there the minimal example that outputs human readable data.

[GoodLug]

Thanks. That gets the same data as the aiobmsble.exe script (once I had worked out how to modify the BMS class entry). What I want to do is get some of the other data/settings stored in the BMS, things like the charge cut off voltage (charging stops when the set voltage is reached) and the over-current protection (in amps, battery shuts down when that current is exceeded).

[GoodLug]

This is the data I currently get (using aiobmsble.exe, minimal.py gets the same data):

[patman15]

Looks good and complete to me. charge cut off voltage is not parsed, the over-current protection is most likely in problem_code if triggered.
Units of the values you can find in the comments here:

aiobmsble/aiobmsble/__init__.py

Line 58 in 7c0ea3e

class BMSSample(TypedDict, total=False):

[GoodLug]

It's complete as you wrote the code, yes, but I am trying to find a way to parse the other data/settings stored in the BMS. This image of JBD Tools from an unknown battery shows some of the settings eg DSGOCP is the over-current protection I mentioned (cuts off at that discharge current). I'm trying to add some of those settings to the list of parsed items.

[patman15]

Such settings might not be in the frames currently parsed. Not sure, I focussed on the "standard data" to be available in most BMS variants.

[GoodLug]

Possibly, though some of the frames are quite large (as seen when connecting via ble-serial), albeit with lots of redundant data (consecutive 00 or FF).

Bearing in mind we are looking at BLE data that is meant for an mobile app, and then reading it for use on a PC, it is possible the data isn't in that data stream (instead, it is in the RS485 cable connection stream that the desktop programs normally use), but I suspect it is available over BLE because the Overkill Solar app can see the protection settings, and it does that over BLE, see image below, where it is connected to a JBD BMS, not sure what battery it is in.

Can I ask, how did you work out how to parse the raw data in the frames to get the human readable values? I might be able to extend that process to find other data.