nRF connect programmer vs. J-flash tool

[SoerenBirth]

Hello there,

if i download a hex-file to the NRF52840-Dongle with the J-Link (Lite) tool, the dongle always remains in bootloader mode (red led is flashing). But if i download the SAME Hex-file with the programmer tool from the nrf connect SDK, the applications starts!

Why what else than programming the hex-file, is the programmer doing?!

regards,

(I attached both (bootloader file and application))

Sören6472.open_bootloader_usb_mbr_pca10059_debug.hex7043.nrf52840_xxaa_mbr_pca10059.hex

[Vidar Berg]

Hello,

I assume you are programming the hex file through DFU over USB when you use the programmer app? This is a bit different from flashing the hex file directly through the debug interface (with a J-link). Because when you do DFU, the bootloader will  automatically update the checksum value used for boot validation (the bootloader verifies the checksum of the application image before deciding to start it on every boot  - Boot validation).

If you want to program the application with the J-link, you also need to generate and program the bootloader settings page along with it, see Generating and displaying bootloader settings.

In case you have not seen it, we have a tutorial specifically for programming of the 52840 dongle here: https://devzone.nordicsemi.com/nordic/short-range-guides/b/getting-started/posts/nrf52840-dongle-programming-tutorial

Best regards,

Vidar