Nordic Dongle nrf52840 is not able to connect to debugger after flashing s132 example

[viet_mai_quoc]

Dear all, 

I have picked the Ruuvi project : https://github.com/ruuvi/ruuvi.firmware.c and change the configuration to adapt with nordic dongle.

But after flashing, my nordic dongle is not able to connect to the debugger, and the dongle doesn't working anymore.

I followed some instruction to recover the nordic dongle like : 

- use external debugger.

- or cut SB2 and solder SB1 then power via VDD, then flash via SWD.

But it doesn't help.

Please give me some of advices, 

thanks.

[Vidar Berg]

Hi,

Just to make sure, have you checked if the external programmer actually supports programming at the target voltage (ie same as VDD voltage after cutting SB2 and shorting SB1). Different logic levels between target and debugger is probably the most common cause of programming issues with the 52840 dongle (this problem is also mentioned in the "nRF52840 Dongle Programming Tutorial"). Next thing I would suggest to try is to run "nrfjprog --recover".

Also, unrelated to the programming issue, but as you may now, s132 is not intended to be run on the 52840 and you may run into compability issues. See Compatibility Matrix - SDKs and SoftDevices for supported SD/SDK combinations.

Best regards,

Vidar