Support with Programming Dongle

[jimctr7]

I was following the article here on programming the nRF52840 Dongle, but am running into issues, and I have other questions as well.

(+) nRF52840 Dongle Programming Tutorial - Getting Started - Short-range guides - Nordic DevZone (nordicsemi.com)

I must not be following completely because screen shot of blinky example - without softdevice - differs a bit, and adding a softdevice is a real mess, as can be seen here.

Obviously something is wrong here, and maybe someone can walk me through this.   Another question I have was posted here but I don't think the question was ever answered in this post.

(+) Nordic DevZone (nordicsemi.com)

The question was about why in nRF Connect Programmer, the greyed out erase, erase and write and save options are brought up.  The person answering this post said it was because we did not want the bootloader erased - makes sense - but then the poster added some valid counter arguments.  He ended with the question whether the write hex encompasses erase-then-write but this was never answered.  The question was with regards to reprogramming the dongle and you really want to erase a sector before writing over it. 

[Kenneth]

I am not sure I have any quick fix or answer for you here. The tutorial you link to says in the beginning: 

"The lack of an onboard debugger means that common debugging techniques such as stepping through code or accessing registers are not possible unless you connect an external debugger. The nRF52840 DK is a better choice for a stand-alone development platform."

I highly recommend getting an nRF52840 DK for development, then you are also free to erase and program whatever firmware you want. The dongle have limitations, since you can't overwrite the MBR and bootloader, thereby programming the Blinky example without a softdevice is not possible either.

With an nRF52840-DK you can run the getting started example:
https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/getting_started_examples.html

[jimctr7]

I have a nRF52840 DK.  I thought it was adequate to have just one, but I want to test the uart ble bridge not just with the phone app but between two kits and I thought that the dongle was adequate for acting as the central device.   The question I was asking was not about debugging, because I am using your code and I assume it should already have undergone thorough debugging.  The question is how to program it.   The tutorial starts out with changing some memory settings (but this is without softdevice).  The problem I am running into is overlap with Softdevice probably due to the memory settings recommended for the nonsoftdevice example.  Is there a step by step guide for programming the USB dongle that includes a softdevice?   This is what I need.  I don't think the tutorial I was looking at was particularly clear on that issue.

[jimctr7]

I reset the memory parameters back to where they were before.  Now there is no overlap between softdevice and programmable image, but I am still not able to program the dongle.  This is what I get:

[Kenneth]

Looks like you have erased the bootloader and thereby it's no longer possible to do DFU over USB, so now you need an nRF52840-DK to re-program the nRF52840 Dongle through SWD.

I recommend to get two nRF52840 DK for development, the nRF52840 Dongle can be used as nRF sniffer, used by nRF Connect BLE app (e.g. to work as a central device), and/or demo of the final application that have been developed using nRF52840-DK. Unfortunately developing an application directly on the nRF52840 Dongle is just very difficult, if you had a dedicated j-link programmer then yes..

Kenneth

[jimctr7]

Thanks for the advice, Kenneth.  I will order another DK kit.  I am a bit confused though.  I thought the red band at the top was the bootloader, and whenever I connect up to nRF Connect with the dongle, it does show up.  Doesn't that mean the bootloader is still intact?

[Kenneth]

Can you try to hold the dongle's RESET button, then connect it to your computer. If the Dongle has entered the DFU mode, the LED pulses red. The Dongle should now be ready for programming. Then try to launch Programmer app from nRF Connect, you can find the dongle and select it to start programming:
https://infocenter.nordicsemi.com/topic/ug_nrf52840_dongle/UG/nrf52840_Dongle/programming.html 

Kenneth