Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Vidar Berg — Tue, 11 Jun 2024 07:14:59 GMT

A development board is much more suited for development since it comes with an onboard Jlink debugger, so it is a good idea to use that. If you get a nRF52840 DK, you can use the second USB port on the side of the board if you later want to test the nRF USB, unless you plan to use a UART-to-USB bridge on your custom board as well.

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Andreas Schurz — Tue, 11 Jun 2024 07:06:11 GMT

Thanks for the response. That makes it all clear. We're planning to use a custom HW rather than the Dongle later, because the missing bridge is making it somehow more complicated. Therefore I will just develop it on a development board using the UART-to-USB bridge in the first step.

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Vidar Berg — Mon, 10 Jun 2024 11:41:45 GMT

The nRF Connect SDK, which you can use to develop the firmware (FW), is primarily written in C. We recommend using it with VS Code and our nRF Connect extension. The hex file from your SDK project can then be programmed to the dongle using nrfutil, the programmer app in nRF Connect for Desktop, or an external debugging probe. Segger embedded studio is not supported in this SDK.

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Andreas Schurz — Fri, 07 Jun 2024 08:09:45 GMT

Thanks for the information but I am still confused.

Could you outine how the actual process from coding till the deployment works then? Which steps have to be taken and which tools have to be used from implementation to deployment?

So I do have to implement the code for the dongle using VS Code or Segger in C?

Using the trigger library to force DFU mode?

Then deploying via nrfutil?

Is this how it works then?

What does FW stand for? Firmware?

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Vidar Berg — Fri, 07 Jun 2024 08:03:36 GMT

Yes, with this approach you will have the BLE application running on the dongle instead of the PC, as you would if you were using the pc-ble-driver. Therefore, any changes to the BLE functionality will require the dongle's FW to be updated. The FW does not have to be based on the Central UART, but I think this sample is the Bluetooth sample that most closely resembles your use case with the relaying of BLE data to the COM port.

DFU Trigger Library (USB) (Note: this has not been ported to the nRF Connect SDK) can be used to force the dongle into DFU mode without physical access to the device. When in DFU mode, you can use the 'nrfutil' tool from the command line to perform the DFU.

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Andreas Schurz — Thu, 06 Jun 2024 15:55:53 GMT

Ok. Thanks so far. This solution should be used in production later on. So pc-ble-driver is NO option then.

So what I understood is then:

We will have to create our own implementation based on the Central UART example for the Dongle bei either using new (VS Code) or old (SEGGER) SDK
It is not possible to change just a Windows EXE on the PC in order to fully change the Dongle BLE implementation
We can reprogram it via DFU - so basically deploy the HEX or DFU.zip

Questions:

Did I get it right?

So the basic assumption from my system architect was that we can implement the complete Nordic BLE functionality in a windows exe without touching the Dongle implentation (no flashing and no-reprogramming). There would be an intial image and all updating in terms of Dongle functionality would be done by changing the windows exe.

In case this is not possible: can the re-programming then be automated, e. g. by using the command line while the dongle is connected. Idea here is to rollout images on a large number of PC-Based self-service machines all across the country and update the BLE implementation if needed. The Dongle will be plugged in all the time so the flash must be triggered remotely while the Dongle is connected. There is no one around who could replug the Dongle...

RE: Using custom BLE image on nRF52840 Dongle with Softdevice API on PC?

Vidar Berg — Thu, 06 Jun 2024 12:38:30 GMT

Hi,

I would not recommend using the pc-ble-driver for production, but it should be fine for testing purposes. In that case, the UART client sample should be a good starting point (https://github.com/NordicSemiconductor/pc-ble-driver/tree/master/examples/nordic_uart_client)

You mention not wanting to re-flash the dongle, but would it be ok to re-program with DFU over USB? This can be performed without user intervention after they have plugged in the dongle and enable you to use a FW based on the nRF Connect SDK (see nRF52840 Dongle Programming Tutorial).

I posted a modified version of the Central UART sample that works with the nRF52840 Dongle here:

RE: Device Tree, proj.conf and strange uart behaviour

This can be modified to use a custom GATT Client for your service and to support multiple connections.

Regards,

Vidar