"no connect "device in nRF Connect for VSCode

[Claudio Rosa]

I have a nRF52840-DK that I know  that it has a JLink on board, but the RAK4631 don´t have JLink, then I am following the RAKWireless bootloader update(Bootloader update ):

1. Press quickly two times the Reset Button, the RAK4631 will go to bootloader mode, and LED green will be on 
2. Execute the bootloader conversion using the command nrfutil.exe dfu serial -pkg rak4631_factory_bootloader.zip -p COM5. Make sure that you have the right .zip file name and COM port number to avoid errors.
3. When I need to become Arduino BSP compatible, I do the follow steps
   1. The previous step updated the bootloader of RAK4631. Another requirement is to ensure that the softdevice is compatible with the expected version by the Arduino BSP. To do this, execute the command adafruit-nrfutil --verbose dfu serial --package rak4631_factory_softdevice.zip -p COM15. You also have to make sure that you have the right .zip file name and COM port number to avoid errors. The COM port will likely be different compared to step 5.

I would like to know how to prepare the RAK4631 to receive MCUBoot and Zephyr.

Could you help me?

Claudio

[Menon]

Hello,

I found a similar case from you, and to me, the issue in both cases appears to be the same. Please let me know if there are any differences. If they are the same, I recommend closing one, as creating two threads for the same issue is not advisable.

Kind Regards,

Abhijith

[Claudio Rosa]

Sorry, You are correct.  I did both because I was not receiving any answer for the first one.  If you want we can go with this one and I will close the first one.

[Joao Dullius]

Hello Claudio,

If you look on RAK4631 (nordicsemi.com), it is stated the following: 

"The RAK4631 board shall be connected to a Segger Embedded Debugger Unit J-Link OB. This provides a debug interface to the NRF52840 chip. You can use JLink to communicate with the NRF52840."

So, you'll need to have an external j-link programmer connected to the RAK4631 j-link interface to program your Zephyr based MCUBOOT bootloader in it.

[Claudio Rosa]

Hi João,

As you can see, RAK4631 is connected with JLink, after some tests with nrfutil, I think that I have some communication problems between JLink and RAK4631.

I will try to prepare (I have to sold a pin bar ) to try to understand where is the problem.

Is this the only way to flash a build ?  I mean with JLink.  Could I do it with USB port?  

Thank you by your suppor.

Claudio

[Menon]

Hello,

I am not entirely sure as I haven't worked with the specific board you mentioned. I reviewed the guide you referred to, but it doesn't specify which bootloader is being used. It mentions the RAK4631 bootloader, which I'm not familiar with. I believe it should be possible to use MCUboot and USB DFU for this. To do so, you can use a JLink to flash MCUboot onto the board. Once MCUboot is installed, you won't need the JLink for future firmware updates; you can use USB DFU or Bluetooth DFU to update the firmware via MCUboot. You may want to follow this guide for configuring the application with MCUboot.

Kind regards,
Abhijith