How to program RedBear Nano without MK20


Hello to all,
I own a redbear nano with an MDBT40 on it. I would like to be able to program it via arduino ide using the SWD interface. I have a SEGGER J-link.

I tried to load the bootloader.hex via nRFgo Studio, so far so good.
After that I compiled a sketch via arduino ide. Now I’m trying to load it via nRFgo Studio using the nRF5xx Bootloader section but with always negative result.

nrf5xx arduino hex

Can someone help me?

Thanks so much.


Hello. Nobody can help me?


Hi @gius, Where did you get the bootloader.hex? Are you sure that the bootloader you loaded to the Nano is Serial DFU enabled?


Hello @guohui,
Thank you for your reply.

I used this bootloader.hex:

I’ve uploaded it normally via nRFGO Studio.
Can I load somehow (using only j-link) a firmware compiled on arduino IDE?


Hi @gius, The bootloader you download from RedBear implements the AVR-DUDE protocol, while DFU using serial bootloader via nRFgo Studio needs the bootloader compiled from the serial DFU bootloader example, which is part of the Nordic SDK. Thus, it must fail when DFU using the nRFgo Studio when your nano is running the RedBear bootloader.