How to change bootloader to uf2 on NRF52840 dongle

[skelly7769]

Im trying to get adafruits UF2 bootloader onto the dongles so i can use my UF2 file for it

i have not gotten the adafruit bootloader onto it 

[Einar Thorsrud]

Hi,

I have no knowledge of the Adafruit UF2 bootloader, but regardless of that, the only way to replace the bootloader on the nRF52840 dongle is via a SWD debugger. So you need to solder on a pin header an use a debugger. Make sure to avoid a reset after doing the chip erase, or use a debugger that can work with varying voltages (ref the section about Using an external debugger in the nRF52840 Dongle Programming Tutorial).

[skelly7769]

Okay. by the way do you know why a program doesnt work for nordic pca10059 dongle version 2.1.1 when it did for 2.0,0?

[Einar Thorsrud]

That depends on the application, but I suspect that it is related to that 2.1.0 introduced revision 3 of the nRF52840, and this is also used in 2.1.1. If the firmware is built with an older SDK, it will not be compatible. See IN-141.

[skelly7769]

It probably was made with older sdk because it was made for the chips inside the VALVE INDEX VR headset. is it possible to contact nordic and change 2.1.1 dongles out for 2.0.0?

[Einar Thorsrud]

We only produce the latest revision and do not keep stocks of old DK's. You could check with some distributors though, perhaps you will get lucky.