DFU - Failed to open transport backend

[c cook]

I followed the Nordic Tutorial located here. I'm using a PCA100028 Dev Board, MCP 3.9.0.6, and a Segger J-Link Plus. I'm using Keil uVision5, and used the pack installer method as described in the tutorial, to load the dual bank dfu example.

When I start the download using the test image (zip file) provided in the dfu folder, I get an "Failed to open transport backend" error.

Why? What's causing this error?

Also - How does one debug the bootloader code? The way the tutorial describes programing the nRF51, there is no way to enter debugging mode.

-Clint

[Hung Bui]

@Nate: Please create another question and have a link to this question. Your issue may not be the same.

[Nate]

It looks like my issue was that I forgot to burn the bootloader. You can see the topic here. Thanks!