Re: RFC: detect and manage power cut on MLC NAND

[Andrea Scian <rnd4@dave-tech.it>]

Dear Jeff,

Il 16/03/2015 22:11, Jeff Lauruhn (jlauruhn) ha scritto:
> Good morning Boris;
> RR is a new feature and not available on all parts few.  I'm not sure 
> about others, but since these are features, you simply enable of 
> disable via SET FEATURE/GET FEATURE.  If you already provide that 
> SET/GET FEATURE functionality then an end-user determine if their 
> device supports a feature and then write the code to enable when they 
> need it on their particular design.

I can confirm this. In fact I'm currently working with two Micron NAND:

MT29F32G08CBACAWP
MT29F32G08CBADAWP

The latter should be "just" a newer die revision of the former (at
least, this is what our distributor says)

There's a technology change between the two and, in fact, the latter
supports RR while there's no mention of such a feature inside rev C.

Jeff, could you please help me in understanding which if the following
sentences are true and which are false?
- rev D is more "robust" than rev C because it has RR (so an additional
feature that improve error correction)
- rev D is "robust" like rev C, if rev D is used with RR
- if RR is not used rev D is more error prone than rev C

I think this is crucial to understand how RR works and how much is
needed inside MTD/UBI code.
I hope that the above information are not under NDA ;-)

Thanks in advance,

--

Andrea SCIAN

DAVE Embedded Systems