DFU of App Data section

RE: DFU of App Data section

Daniel — Wed, 04 Oct 2017 14:23:52 GMT

So you meant you want a special DFU update that will do "factory reset" when normal DFU update will keep the DFU_APP_DATA_RESERVED ?

Correct.

I would suggest to either modify the bootloader to erase the region when you receive the "factory reset" command, or if you don't want to modify the bootloader, you can have some code in your application that can erase the region before you switch to bootloader (assume you have buttonless DFU) .

Thanks. I'd prefer that the functionality wasn't in the application (in case the app data contents cause the application to behave unexpectedly). That leaves updating the bootloader.

RE: DFU of App Data section

Hung Bui — Tue, 03 Oct 2017 15:35:24 GMT

So you meant you want a special DFU update that will do "factory reset" when normal DFU update will keep the DFU_APP_DATA_RESERVED ?

I would suggest to either modify the bootloader to erase the region when you receive the "factory reset" command, or if you don't want to modify the bootloader, you can have some code in your application that can erase the region before you switch to bootloader (assume you have buttonless DFU) .

RE: DFU of App Data section

Daniel — Mon, 02 Oct 2017 18:07:47 GMT

Understood. For my application, I've increased the number of pages to 4 and set DFU_APP_DATA_RESERVED to 0x4000 to match (nrf52832, virtual page size is 1024).

The issue is that I normally do not want to erase this region during a DFU. It's only during special situations, such as a factory reset, that the region should be erased.

RE: DFU of App Data section

Hung Bui — Mon, 02 Oct 2017 13:03:38 GMT

If you have a look here, you can find that by default the application data reserved is 3 pages. If you set DFU_APP_DATA_RESERVED to 0, the application data should be erase.

RE: DFU of App Data section

Daniel — Fri, 29 Sep 2017 20:20:23 GMT

One way I think will work is to increase the size of the application so that it includes addresses up to 0x78000.

This method won't work either. The bootloader will refuse to overwrite the app data section. (And I don't want it erased during a normal DFU, so I have set DFU_APP_DATA_RESERVED appropriately).

-- Daniel