J-Link Programming external nRF52 : Failed to connect to target, no Idcode detected

[StephaneJ]

Hi,

I'm currently programming a custom board using a nRF52832 (using this wiring). Everything was working great but I tried to play with SAADC and maybe did a wrong configuration and/or added too much debug log. Since a previous code upload, I'm unable to connect to my board again.

I had another board with the same behavior (same code uploaded to confirm this was the code), but somehow I found a way to unlock it, I was able to upload a basic blinky example while removing the GND DETECT and switch from VDD to VDD nRF. I don't know if it related though.

But I still have one board completely locked, how to unlock it ?

> JLinkExe -device NRF52 -if SWD -speed 1518 -autoconnect 1

SEGGER J-Link Commander V6.22a (Compiled Nov 28 2017 17:57:01)
DLL version V6.22a, compiled Nov 28 2017 17:56:49

Connecting to J-Link via USB...O.K.
Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 24 2017 17:30:12
Hardware version: V1.00
S/N: 682621274
VTref = 3.300V
Device "NRF52" selected.


Connecting to target via SWD
Cannot connect to target.
J-Link>

Thanks

[Håkon Alseth]

Hi,

 

Since it detects 3.3V, it looks like you have the wiring setup correctly.

Have you tried using nrfjprog to recover the device, like this: "nrfjprog --recover -f nrf52"?

The current consumed by your custom board can also be a good indicator if there's something wrong. Have you checked this?

Cheers,

Håkon

[StephaneJ]

Hi Håkon,

Yes I tried it, here are the log :

> nrfjprog --recover -f nrf52

Recovering device. This operation might take 30s.
ERROR: Recover failed. Please make sure that the correct device family is given
ERROR: and try again.

About the current consumption I'm not sure how I should measure it, I'm more a software person. But as far as I checked, there was no difference on the board compared to a functional one.

For a broken and working board results are the same, plugged to the nRF52DK, I have 2.79V coming out of the regulator and the VDD, VDD_2 and VDD_3 of the nRF52 are 2.79V.

I checked the VDD coming out of the nRF52DK : 2.82V.