Flash download failed - "Cortex-M4"

[SergeyP]

I successfully used my nrf52DK with latest production SD 132 and latest SDK (12.2.0), everything is on latest Keil v5. Then I needed to program another board (nRF51 Dongle) by using the same Keil, I failed with that and eventually wanted to switch back to my nrf52DK but I am no longer able to program the board by using the same project which was used prior to the Dongle "exercise" now my attempt to load the program results in

so I went to Options->Debug->Settings combobox and saw there ULINK2/ME Cortext Debugger, I don't think I explicitly made change there, seems like that setting was somehow got corrupted from my previous experiments with the Dongle. So I changed that value to J-Link/J-Trace Cortext but now my attempt to Load results in:

These are my settings:

Why did this issue started appearing and how to fix it? And would also be good to figure out how to avoid such problems in future.

[Edit/Addition] This is the target settings for the Dongle:

This is the Debug settings for the Dongle:

And this Target for the nrf52DK:

And this is Debug for the nrf52DK:

[Nguyen Hoan Hoang]

The nRF51 dongle and the nRF52DK are not the same chip. The dongle is nRF51822 while the nRF52DK is the nRF52832. 2 different MCU

[SergeyP]

Yes, I knew about the difference and I did take that into account while setting the target, I just updated my original question with 2 additional screenshots showing more details. By the way, my Dongle is actually nRF51422. To reiterate the issue I am experiencing: Keil settings got somehow corrupted once I just loaded another project for a different (10028) target, once I returned back to my original project with 10040 target I got the issue described in my original question.

[Nguyen Hoan Hoang]

Have you check the settings the debug section. It may not changed.

[SergeyP]

I don't know what those settings should look like, I am just opening Keil project for an appropriate target (10028, 10040) and I expect each project file has everything it needs to correctly setup Keil. I have added Debug settings screenshots for both of my cases into the original question.

[Sigurd]

Hi,

According to the IROM settings in Keil you are trying to flash an example that is not using the SoftDevice (IROM1 Start at 0x0 and IRAM1 Start at 0x20000000). If you previously loaded the nRF52-DK with the S132 Softdevice, the SoftDevice will be located in the flash region you are trying to write your application to. You will have to erase the SoftDevice, or adjust the IROM/IRAM settings.