Problem with DFU via USB (nRF52840 & Windows 7)

RE: Problem with DFU via USB (nRF52840 & Windows 7)

Pete W — Fri, 06 Nov 2020 19:48:24 GMT

It's now working with just the MBR hex loaded, and my application origin set to 0x1000.

RE: Problem with DFU via USB (nRF52840 & Windows 7)

Pete W — Fri, 06 Nov 2020 19:25:49 GMT

I meant s140, obviously :-)

RE: Problem with DFU via USB (nRF52840 & Windows 7)

Pete W — Fri, 06 Nov 2020 19:24:39 GMT

Hi Hung,

Thanks for the reply. I've managed to get it working but only if I program the softdevice rather than the small MBR on its own, but at least this proves that my keys are correct and that I'm building the package correctly. I'd just like to be able to do it using the MBR hex on its own, rather than loading the s40 softdevice, as my application doesn't require the bluetooth stack. Is that possible?

- Peter

RE: Problem with DFU via USB (nRF52840 & Windows 7)

Hung Bui — Mon, 02 Nov 2020 14:07:40 GMT

Hi Peter,

The bootloader was responded with "Invalid Object" it's most likely because of the init packet was not accepted. Can either be because the signed hash was not match with the public key in the bootloader, or if you have the wrong softdevice ID.

My suggestion is to test with a very simple application that blink the LED. Configure it to start at address 0x1000 and don't use the softdevice. We can come back to use the softdevice after we have DFU working.

Next please double check that you used the correct public-private key pair in the bootloader and when you generate the .zip DFU image file.

Please include all the steps you do to generate the keys, generate .zip file etc.