recover nrf52 DK

[Neum_d]

Hi all!

I just bought a new nrf52DK: PCA10040, 3.0.0, 2023.10
If I want to flash my SW into it, nrfjprog says

ERROR: The operation attempted is unavailable due to readback protection in
ERROR: your device. Please use --recover to unlock the device.

So I run nrfjprog --recover -f nrf52.
After that, I try to flash my FW, but nrfjprog returns

ERROR: The file specified is not a valid hex file, has data outside valid areas
ERROR: or does not have data in valid areas.

If I plug off the DK and replace it by my old nrf52 DK (PCA10040, 1.2.4, 2019.8), I have no
problems to flash my SW, so the hex file itself should be valid. Does the new DK
require more parameters to nrfjprog?

Additional, if I replace the old DK with the new DK again, the new DK is locked again,
and I have to --recover it again. Is there a way to make the unlock persistent?

Thanks in advance,

Dirk.

[Håkon Alseth]

Hi,

 

With newer revisions of the nRF52 SoC family, a hardened approtect is added, which requires handling in the firmware to open up the debugger session:

https://infocenter.nordicsemi.com/topic/errata_nRF52832_Rev3/ERR/nRF52832/Rev3/latest/config_832_249.html?cp=5_2_1_0_2_0

 

Is your firmware compiled with newer startup files (MDK)?

 

So I run nrfjprog --recover -f nrf52.
After that, I try to flash my FW, but nrfjprog returns

which version of nrfjprog are you using? Could you share the output of "nrfjprog -v"?

 

Kind regards,

Håkon

[Neum_d]

If I understand the linked explanation correct, I just add NRF_UICR->APPROTECT=0xFF; to my main() ?

I use nrfjprog version 10.12.2:

$ nrfjprog -v
nrfjprog version: 10.12.2 
JLinkARM.dll version: 6.88a

[Håkon Alseth]

Hi,

 

Neum_d said:

If I understand the linked explanation correct, I just add NRF_UICR->APPROTECT=0xFF; to my main() ?

That will lock down the device, so that you'll need to recover each time you reprogram.

Set it to 0x5AUL; to open it up.

 

It is strongly recommended that you update to MDK version 8.40.2 or later:

https://www.nordicsemi.com/Products/Development-tools/nRF-MDK

 

Neum_d said:

I use nrfjprog version 10.12.2:

Could you try to update nrf-command-line-tools to a newer version?

 

Kind regards,

Håkon

[Neum_d]

Thanks. I updated MDK and nrfjprog and now it seems to work. I have to check, if my program does the things still correct.

BTW: The connectivity firmware which comes with nrfutil 6.1.7 seems to use a MDK which is too old...

[Neum_d]

I just saw that updating to MDK 8.53.1 prevents me to use FDS to store data into flash. I assume I have to take additional steps to re-enable it. I opened with NRF_UICR->APPROTECT = APPROTECT_DISABLE_DISABLE_SwDisable, but no success. I assume, I have to change some  other things too, is there a porting guide for the MDKs?

[Håkon Alseth]

The handling of approtect is done in the startup files, so no need to add anything in your application when using MDK v8.40.2 or newer. 

Neum_d said:

MDK 8.53.1 prevents me to use FDS to store data into flash.

How do you mean? You're not able to write to internal flash from the mcu anymore? This sounds like a different issue.

 

Kind regards,

Håkon

[Neum_d]

Yes. If I switch back to the old MDK 8.24.1, I can write into internal flash, but no more, if I use 8.53.1. Then, fds.c::record_header_write_begin() does not return and the whole system hangs (until watchdog causes reboot), even if fds_record_update() is called in the context of app_scheduler.

[AHaug]

Hi,

Håkon is out of office now on vacation for the next weeks. Based on what I can see and what Håkon states it looks like this latest issue is a new issue. I recommend you to create a new case and we will assign it to an available engineer to look into it over the summer. Do however note that we're in the main summer vacation period here in Norway, so responses will be slower than usual until mid August.

Kind regards,
Andreas