nrf52832-QFAB Flash/RAM sizes

RE: nrf52832-QFAB Flash/RAM sizes

motion — Mon, 19 Feb 2018 20:08:00 GMT

Thanks, Sigurd. Good to hear it's in the errata and an issue on Rev 1 only.

RE: nrf52832-QFAB Flash/RAM sizes

Sigurd — Mon, 19 Feb 2018 12:57:29 GMT

Hi motion,

Errata 163 have been created to cover this issue. Note that the anomaly only applies to nRF52832 Rev 1 with build codes QFAB-B00 (256 kB flash / 32kB ram variant).

RE: nrf52832-QFAB Flash/RAM sizes

motion — Fri, 16 Feb 2018 20:23:29 GMT

Any updates on this? This answer is unacceptable. Apparently I hold Nordic to a higher standard than this answer suggests I should.

RE: nrf52832-QFAB Flash/RAM sizes

Roger Clark — Tue, 14 Feb 2017 23:17:12 GMT

Interesting point about the

FICR.INFO.RAM reporting incorrectly. I suppose this should be treated as a bug in the silicon ? I know that the first release of nRF52 has a lot of errata, perhaps this was one of those

It sounds like you have to just use the FICR.INFO.VARIANT rather than the FICR.INFO.RAM

RE: nrf52832-QFAB Flash/RAM sizes

RK — Tue, 14 Feb 2017 22:42:22 GMT

At the least if this is the case there should be a PAN about it documenting that the FICR registers describing the FLASH/RAM of the chip are not reliable and cannot be used, with a documented workaround using the VARIANT, and that PAN should persist until the anomaly is fixed.

RE: nrf52832-QFAB Flash/RAM sizes

jlj — Tue, 14 Feb 2017 22:11:08 GMT

I don't use undocumented features or go beyond specs in my commercial designs, for the very reasons you've mentioned. My main concern here is knowing what to trust when the FICR registers have incorrect or conflicting information. Unfortunately this is one of those cases where the silicon does not match the datasheet. We may end up having both variants used in the same production environment and I'd like to be able check in code that the right part is loaded.

RE: nrf52832-QFAB Flash/RAM sizes

Dave — Tue, 14 Feb 2017 21:54:08 GMT

I agree with RK and awneil. As a developer I need a software means to query the part and know what I am using. I wasted half a day to debug some fds/fstorage code only to determine that the CODESIZE value being returned was bogus, 128 for 512KB part when I am using a 256KB part and it should have been 64 instead. That is a bug that should be addressed and fixed by NS.

RE: nrf52832-QFAB Flash/RAM sizes

awneil — Tue, 14 Feb 2017 12:02:58 GMT

I think if you have registers which indicate the capabilities of the chip, they should indicate correctly the capabilities of the chip and developers should be able to rely on them.

Absolutely!

RE: nrf52832-QFAB Flash/RAM sizes

RK — Tue, 14 Feb 2017 11:57:00 GMT

That's a pretty sad answer really. The whole point of having RAM, FLASH and CODEPAGE entries in the FICR is exactly so you can work out the capabilities of the chip without having to map variant codes, codes which change as time goes by, with different production runs etc, to capabilities. All of the Nordic code I've seen in the past which deals with memory capabilities all uses CODEPAGESIZE etc to work out what's there, I don't think I've ever seen a piece which uses VARIANT and tries to map it. In fact a quick grep of the most recent SDK shows no use of VARIANT.

I think if you have registers which indicate the capabilities of the chip, they should indicate correctly the capabilities of the chip and developers should be able to rely on them.

RE: nrf52832-QFAB Flash/RAM sizes

Roger Clark — Tue, 14 Feb 2017 10:23:47 GMT

Devices with more RAM or more flash than the spec is not uncommon in the microcontroller world.

But if you are building for a commercial product, you should not assume that a one off instance of a specific device performing beyond its spec will be replicated by all other devices of the same type.

RE: nrf52832-QFAB Flash/RAM sizes

FormerMember — Tue, 14 Feb 2017 10:03:08 GMT

The nRF52832-QFAB device is specified in the Product Specification to 256kB Flash and 32kB RAM. Utilizing any Nordic device outside of the specifications for the given part can give unpredictable behavior, and Nordic is in no way liable for the functionality nor specification at this point, and it is as such not something we encourage anyone to do. If you want additional details on the risks associated with using a Nordic device outside of the specification, please get in touch with a local sales representative.

To check the capabilities you should check the FICR.INFO.VARIANT register.

RE: nrf52832-QFAB Flash/RAM sizes

jlj — Sat, 11 Feb 2017 23:12:51 GMT

No, I'm only referring to the nRF52 devices (nRF52832-QFAB and nRF52832-QFAA)

RE: nrf52832-QFAB Flash/RAM sizes

FormerMember — Fri, 10 Feb 2017 08:52:03 GMT

Do you mean nRF51822 instead of nRF52832?