Difference in reset between nRF52840DK and dongle?

RE: Difference in reset between nRF52840DK and dongle?

Fredcoach — Sun, 04 Aug 2019 12:17:53 GMT

It is used to flash the device, provides a virtual COM port and is seen externally as a disk drive. Thus it should be the on-board J-Link. And we do not program any USB device.

RE: Difference in reset between nRF52840DK and dongle?

awneil — Fri, 02 Aug 2019 19:57:39 GMT

[quote userid="81465" url="~/f/nordic-q-a/50575/difference-in-reset-between-nrf52840dk-and-dongle/202227"]I also flash the DK using the USB[/quote]

There are two "USBs" on the nRF52840DK

one for the on-board J-Link
https://infocenter.nordicsemi.com/topic/ug_nrf52840_dk/UG/nrf52840_DK/if_mcu.html?cp=3_0_4_6
one for the nRF52840's own USB

RE: Difference in reset between nRF52840DK and dongle?

Fredcoach — Fri, 02 Aug 2019 19:27:36 GMT

Ok, I'll also try this, thanks.

RE: Difference in reset between nRF52840DK and dongle?

Fredcoach — Fri, 02 Aug 2019 19:27:04 GMT

I also flash the DK using the USB.

But there should not be any reset at all, thus the bootlader should not have to run.

RE: Difference in reset between nRF52840DK and dongle?

awneil — Fri, 02 Aug 2019 19:10:44 GMT

[quote userid="81465" url="~/f/nordic-q-a/50575/difference-in-reset-between-nrf52840dk-and-dongle/202216"]To be completely sure, I just reflashed the softdevice[/quote]

To be completely sure, you should do a full chip erase first.

RE: Difference in reset between nRF52840DK and dongle?

Turbo J — Fri, 02 Aug 2019 18:30:41 GMT

The Dongle has an USB bootloader, the DK has a JLink that talks directly to the NRF chip via SWD.

Without the USB bootloader you would need to connect a debugger via SWDIO an SWDCLK to the dongle in order to program the device.

And yes, the bootloader runs at every Reset before the application even starts.

RE: Difference in reset between nRF52840DK and dongle?

Fredcoach — Fri, 02 Aug 2019 16:49:06 GMT

Is the bootloader different in nRF52840DK and the dongle?

I loaded the same softdevice and the bootloader is supposed to be included in it...

To be completely sure, I just reflashed the softdevice and the problem is still there.

RE: Difference in reset between nRF52840DK and dongle?

Turbo J — Fri, 02 Aug 2019 16:10:36 GMT

Maybe the bootloader on the dongle kills RESETREAS bits in order to be able to properly run when called by the application?