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bleak.exc.BleakError: Characteristic was not found!

See original GitHub issue

bleak version: 0.9.1 / 0.8.0
Python version: 3.8.6 / 3.8.4
Operating System: Windows 10 / Debian 10 (RPi3b+)
BlueZ: bluetoothctl: 5.50

Description

I’m trying to connect to a BLE device via bleak - it works fine when I use my script on Windows 10, but the same script fails on Linux:

bleak.exc.BleakError: Characteristic 11111111-1111-1111-1111-111111111111 was not found!

What I Did

My code:

from bleak import BleakClient
import asyncio


address = "xx:xx:xx:xx:xx:xx"
ble_uuid = "11111111-1111-1111-1111-111111111111"

msg = b'ABC'
async def run(address, loop):
        async with BleakClient(address, loop=loop) as client:
            await client.write_gatt_char(ble_uuid, msg, True)

loop = asyncio.get_event_loop()
loop.run_until_complete(run(address, loop))

The difference I see is a different bleak version on Win and on Linux. On Linux pip3 install bleak returns only bleak 0,8.0:

pip3 install bleak
Defaulting to user installation because normal site-packages is not writeable
Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
Requirement already satisfied: bleak in /home/pi/.local/lib/python3.8/site-packages (0.8.0)

Traceback (most recent call last):
  File "script.py", line 13, in <module>
    loop.run_until_complete(run(address, loop))
  File "/usr/local/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
    return future.result()
  File "script.py", line 11, in run
    await client.write_gatt_char(ble_uuid, msg, True)
  File "/home/pi/.local/lib/python3.8/site-packages/bleak/backends/bluezdbus/client.py", line 580, in write_gatt_char
    raise BleakError("Characteristic {0} was not found!".format(char_specifier))
bleak.exc.BleakError: Characteristic 11111111-1111-1111-1111-111111111111 was not found!

Issue Analytics

State:
Created 3 years ago
Comments:51 (7 by maintainers)

Top GitHub Comments

1reaction

dlechcommented, Aug 19, 2022

INFO:__main__:		[Descriptor] 00002902-0000-1000-8000-00805f9b34fb (Handle: 17): Client Characteristic Configuration) | Value: b''

The value should be two bytes, so there appears to be a problem with the remote device itself.

1reaction

Divya-nemuricommented, Aug 9, 2022

im getting the same issue bleak.exc.BleakError: Characteristic UUID was not found! while trying to connect to a ble device from a linux PC, i tried all the above things. i tried with both uuid’s which i got from client.get_services()

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