Possible to write to flash in the app error handler?

[Pablitorun]

What would be the best way to store configuration and fault information in flash when the app_error_handler is called?  It seems like all the libraries available are purely async so I don't know if they would work for me.

[awneil]

Save the stuff to a RAM area that doesn't get initialised at startup, then do a reset.

When the code re-starts, save the stuff from RAM to Flash ...

[pablitorun]

Yeah I was wondering if that would be the best, having trouble getting that working with the bootloader however.

Without the bootloader it seems to work great.

[awneil]

Never tried it with a bootloader.

I guess you'd need to make sure that neither the bootloader nor the app cleared the "persistent" area ... ?

[pablitorun]

I was able to get it to work following the instructions here

https://devzone.nordicsemi.com/f/nordic-q-a/33530/ram-variables-exchange-between-bootloader-and-application

The key seemed to be making sure it was in it's own section and page for both the bootloader and app.  Not sure why that would matter, but I am for sure not an expert on the linker.

[Richard D.]

The GPREGRET registers are available if your data fits in 16 bits (2x8)