Programing extrnal NRF52840

[matija66]

Hi,

I am trying to program an extrnal nrf52840 it is Minew MS88SF2, I did exactly as desribed here at least I think I did, but unfortunatly it always programs the internal NRF. I measured power supply voltage on external NRF and double cheked connections with multimeter it seems OK. I am using Mbed Studio.

Do you have any suggestions what else can I try?

Thank you very much.

Also I should mention I am able to program board using J-link EDU mini and NRF connect.

[Marjeris Romero]

Hi,

Sorry for not getting back to you before. Don't you have another 10-pin cable you can try to use with P19?

Can you also check if SB40 is shorted or not? Some old versions of the kit came with this bridge unshorted. You can check the version of the kit you have under the "PCA10095" name.

Have you check that you haven't swapped SWDIO and SWDCLK in your external board?

Since LED5 is ON there are high changes that you kit is working, but that is was shipped with no firmware, perhaps you have an old version of the kit.

Best regards,

Marjeris

[matija66]

Hello,

Yes I also tried with P19 pin and SB47 shorted, what is weird about this is as I mentioned before on board nrf gets programmed even though Development Kit User guide states that this is not posible.

Yes I checked SWDIO and SWDCLK pins.
Info from board:
PCA10056
2.0.1
2020.38
683017179

Best regards.

[Marjeris Romero]

Hi,

This is a bit weird yes. Could you try to cut SB54 and SB55? This will cut the SWD interface to the onboard nRF chip so it should be impossible to program then.