nRF52 DK does not seem to boot?

RE: nRF52 DK does not seem to boot?

Lars Fagerbakke — Wed, 20 Jun 2018 08:15:56 GMT

Phew... it's alive!

It did not seem to power on in normal more but after a few tries I got it into bootloader mode. I headed over to mbed and downloaded the bootloader/firmware then the led (LD5) switched from long blinking (2s on, 2s off) to rapidly blinking. It stayed like that for 10-15 min so I did something crazy and powered the DK down. Lucky for me the process was done it seems, because I could now start the DK as usual without holding the reset button.

Disk "DAPLink" became available in my computer. I had "JLINK" before. So I downloaded "J-Link OB-SAM3U128-V2-NordicSemi 170724" from Nordic site. You guys should rename it to layman terms. The name does not give away that its the firmware (for the bootloader(?), unsure of the terminology there).

But I powered down and up the DK again, this time with reset pressed and got into bootloader mode yet again. Dropped in the bin file from Nordic and same process again. The blinking rate changed (faster) and it stood there for about 10 min. The process should end with a reboot because you don't know when the process is done... Brings back memories from the yearly 00s when I first updated the firmware for the one of mobo in my first computers. Felt scary as I didn't want to break it :-).

But the DK is back online again. Running "blinky" application from the SDK. Time to get down to business! :-)

RE: nRF52 DK does not seem to boot?

Susheel Nuguru — Tue, 19 Jun 2018 12:30:56 GMT

is this LED5 that is blinking rapidly? If yes, then it must be something with DAPLink firmware. I have similar blinking when I JLink firmware on my PC has problem communication with theOB Debugger chip. I dont know much of DAPLink internals, so cannot know what is wrong here

RE: nRF52 DK does not seem to boot?

Lars Fagerbakke — Tue, 19 Jun 2018 08:15:00 GMT

I got it to go into bootloader mode and downloaded bin file from https://armmbed.github.io/DAPLink/?board=Nordic-nRF52-DK. Now its rapidly flashing. Its done that for about 10 min maybe.

RE: nRF52 DK does not seem to boot?

Susheel Nuguru — Tue, 19 Jun 2018 07:57:56 GMT

Could it be that the dip switches got changed which select the power source.

Please read the DK user guide here section 8.3.4 to see if the settings are correct for the dip switches.