mbed app loaded to drive works, downloaded to firmware does not

[mark waldin]

quick-stop_2_with_soft_filter_NRF52_DK (1).hexI imagine that my question is just one from lack of experience. I apologize for that but I cannot find any information on the Internet to address this problem. I load my mbed developed app hex file to the nrf52 DK by copying to JLINK drive and it works great.

Now wanting to load it to firmare and used nrfjprog to write it to firmware. Write went fine. Did a compare to check it was loaded and no problem but it does not run when I do a reset or on/off.

Can you guide me to what I am missing?

Thank you, Mark

[Jørgen Holmefjord]

You should be able to program the application using nrfjprog if it works with drag-and-drop programming. What command are you using for flashing using nrfjprog? Could you upload the hex file in question for testing?

[mark waldin]

thank you for the response. the command I used was nrfjprog -f NRF52 --quick-stop_2_with_soft_filter_NRF52_DK(1).hex –-chiperase

I attached the file to the original submittal. thank you for looking at this

[Jørgen Holmefjord]

I tested your firmware and do see the same issue, however when I try with a different firmware generated by mbed online compiler, I'm able to flash it using both drag-and-drop and with nrfjprog. What version of mbed os are you using?

[mark waldin]

I am using the online compiler also. You mention flashing your code with both drag and drop as well as nrfjprog. From my experience using the drag and drop I was under the impression that the code loads to ram and is not flashed. I say this because when i use the drag and drop the code executes immediately without needing to do a reset and when I turn the board on and off the code no longer runs. Am I incorrect?

[mark waldin]

Ok. I thought it was loading to ram instead of flash because it disappeared after on/off. I see there is not enough ram to hold the file anyway so I understand both methods do the same thing. Odd they work differently. However I did find the source of the problem (not the solution) and have added it below as a reply. Thanks for helping me.