Hi,
I'm mid-way through designing a custom board using the nRF52840. As I am space and height constrained I need to use the Tag Connect style connector used on the nRF52840 Dongle and DK boards. This looks like a neat solution and I'm all ready to go except....
I want to use the DK as a programmer and I have read this can be done using the Debug Out connector P19. As I'm checking my schematics, I notice that on the Dongle schematic pin 5 is connected to VBUS' yet on the DK, pin 5 of P19 is connected to ground.
According to the Segger website and their specification for the same connector style (they call it a Needle connector), pin 5 is used to power the board to be programmed - this makes sense. See https://www.segger.com/products/debug-probes/j-link/accessories/adapters/10-pin-needle-adapter/ for more information.
So, my question is this... can the DK be used to program an external board using the pin out suggested in the Dongle's schematic? I don't think you can because you will end up shorting VBUS to GND if you do a 1:1 pin mapping. I think that pin 5 needs to be a no-connect, but I'm just checking before I commit to copper.
Has anyone else done this before?
Thanks,
Simon