nRF Dongle as UART client python

RE: nRF Dongle as UART client python

Jørgen Holmefjord — Mon, 17 Oct 2022 07:31:28 GMT

Please post a new ticket regarding your problem. This is a very old post, pc-ble-driver-py might have changed and causing the problems your are experiencing.

RE: nRF Dongle as UART client python

Alvin_99 — Sun, 16 Oct 2022 03:14:41 GMT

Hi Jagen,

I'm currently working on sending command with the python script with the method that you suggested but seems like I'm still getting the error code. I had been struggling with this issue for quite sometime so your help will be greatly appreciated.

Below are my error code.

  File "Command.py", line 244, in main
    collector.write_word_characteristic(conn)
  File "Command.py", line 226, in write_word_characteristic
    self.adapter.write_req(conn_handle, NusCollector.CUS_WR_UUID, byte_array)
  File "C:\Python38\lib\site-packages\pc_ble_driver_py\ble_driver.py", line 104, in wrapper
    err_code = wrapped(*args, **kwargs)
  File "C:\Python38\lib\site-packages\pc_ble_driver_py\ble_adapter.py", line 487, in write_req
    raise NordicSemiException("Characteristic value handler not found")
pc_ble_driver_py.exceptions.NordicSemiException: Characteristic value handler not found

RE: nRF Dongle as UART client python

Jørgen Holmefjord — Thu, 18 Jan 2018 12:15:07 GMT

Note that this instructions was written for an older version of pc-ble-driver-py, they might not work with the current latest version. Please create a new question where you post what you have tried, and we will help you get it working.

RE: nRF Dongle as UART client python

Sebastien Monat — Wed, 17 Jan 2018 15:04:27 GMT

Hi. So gannerud do you succeded to do what you want on your original POST ? I want to do exactly the same thing and I follow the advices of Jorgen but I still have the error pc_ble_driver_py.exceptions.NordicSemiException: Characteristic value handler not found

Should I add my BLE BASE_UUID or should I add the one you write on the post Jorgen ? I'm a bit confused ...

Could you give me some help ?

Thanks

RE: nRF Dongle as UART client python

gannerud — Tue, 27 Sep 2016 11:35:25 GMT

Thank you! This helped me alot!

RE: nRF Dongle as UART client python

Jørgen Holmefjord — Tue, 27 Sep 2016 11:21:37 GMT

I updated my answer above with the description of enabling NUS.

RE: nRF Dongle as UART client python

gannerud — Tue, 27 Sep 2016 06:06:19 GMT

Hi thanks for your response. I'm have looked at the heart_rate_collector example and I get connected to my peripheral but when i try to write to it with write to a custom uuid (Nordic UART Service, 6E400002B5A3F393E0A9E50E24DCCA9E) I get an exception File "C:\Python27\lib\site-packages\pc_ble_driver_py\ble_adapter.py", line 282, in write_cmd raise NordicSemiException('Characteristic value handler not found') What shall a custom write_cmd look like?

RE: nRF Dongle as UART client python

Jørgen Holmefjord — Mon, 26 Sep 2016 13:03:22 GMT

Hi,

You can use pc-ble-driver-py to communicate with peripherals from your python program. See the examples in python/pc_ble_driver_py/examples for help getting started.

[EDIT:]

To use the Nordic UART service to read and write data, you have to add the UUIDs to your driver. An example of how this is done can be seen in the source of the BLE transport layer for the DFU service in nrfutil.

Based on the HRS example code, adding the corresponding UUIDs for NUS will then be as follows.

Define the UUIDs inside the HRCollector class:

    BASE_UUID     = BLEUUIDBase([0x6E, 0x40, 0x00, 0x00, 0xB5, 0xA3, 0xF3, 0x93, 
                                 0xE0, 0xA9, 0xE5, 0x0E, 0x24, 0xDC, 0xCA, 0x9E])
	NUS_TX_UUID   = BLEUUID(0x0003, BASE_UUID)

Add your BASE_UUID to the driver (in HRCollector.open()):

self.adapter.driver.ble_vs_uuid_add(HRCollector.BASE_UUID)

Enable notification (in HRCollector.connect_and_discover()):

self.adapter.enable_notification(conn_handle=new_conn, uuid=HRCollector.NUS_TX_UUID)

Best regards,

Jørgen