Where should I put manufacturing value?

RE: Where should I put manufacturing value?

Rune Holmgren — Tue, 06 Mar 2018 14:59:03 GMT

Yes, you may do this. The bootloader only knows what region to avoid and is unaffected by where in this region FDS is working. Moving FDS and non-FDS data around within the reserved area is not a problem.

Take care when making such changes though since there isn't any way to recover erased data if your device happens to have an issue with the configuration which causes FDS to overwrite manufacturing values.

Best regards,
Rune Holmgren

RE: Where should I put manufacturing value?

yuxin — Wed, 28 Feb 2018 03:49:29 GMT

good idea

RE: Where should I put manufacturing value?

yuxin — Wed, 28 Feb 2018 01:35:07 GMT

i don't konw....

RE: Where should I put manufacturing value?

rabarton — Tue, 27 Feb 2018 22:57:17 GMT

Actually one follow up question is if we were to modify the FDS lib so that we could specify the address range used, do you see any issue with putting manufacturing values just below the bootloader in a 4KB block, and then app data below that? With this change we would have the option to grow the app data in the future. (I realize this may not be trivial with how FDS data is stored in flash)

RE: Where should I put manufacturing value?

rabarton — Tue, 27 Feb 2018 21:52:04 GMT

Thank you for the explanation Rune. This will work. I'll probably want to grab a 4KB block below the FDS area so I can turn on PROTENSET protection in the bootloader. Request for a future product would be a few lockable flash/registers so we don't need to use 4KB of flash. As things are designed, we need to estimate future size of the bootloader, and future size of the app FDS data and put our manufacturing values below that which is fragmenting flash quite a bit.

Thanks again for the answer!

RE: Where should I put manufacturing value?

Rune Holmgren — Tue, 27 Feb 2018 17:04:10 GMT

Hi,

(This is a slightly edited version of the nRF52 answer given to the user kentaharada in this question) There are two different answers for systems with and without a bootloader:

Without a bootloader, you should store these data in the last flash page on the device towards the top of the device flash area. Typically 0x3FC00. Ensure that there are no other flash operations in this area done by the application.

With a bootloader, you should store these data in a flash page in the "Application data" area in a region before the FDS pages. The default in the bootloader project is that the "Application data" area is 3 pages determined by the define DFU_APP_DATA_RESERVED. The default in most of the SDK applications using peer_manager is that the FDS uses 3 virtual pages with a page size equal to 1 physical page determined by the define FDS_VIRTUAL_PAGES. If you set the size of the "Application data" area to 1 page larger than the FDS area this additional page can be safely used to store data. It will never be written to by the bootloader because it's in the "Application data" area, and it will never be written to the by the FDS because it's outside the FDS area. I have added an annotated flash map below showing where this page will be:

Best regards,
Rune Holmgren

RE: Where should I put manufacturing value?

Ronnie Bajwa — Mon, 26 Feb 2018 08:05:06 GMT

I’d love to know the official response from Nordic as well...

RE: Where should I put manufacturing value?

Kenta Harada — Mon, 26 Feb 2018 02:01:51 GMT

Similar to my question. But no response from Nordic.

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