Recover failed SD card

[@lbutlr]

On 24 Feb 2019, at 07:34, Valeri Galtsev <galtsev at kicp.uchicago.edu> wrote:
> On 2/23/19 6:46 PM, @lbutlr wrote:
>> On 23 Feb 2019, at 13:50, Bruce Ferrell <bferrell at baywinds.org> wrote:
>>> Unfortunately flash memory "wears out".  There are spare storage blocks and logic to level wear by switching th the spares when main block failures are detected.
>> Yeah, that’s good theory, but it’s not what has happened with mine. Genrally they fail in the first few weeks. Even if it takes longer, it is not like they have been written and rewritten  many times. This isn’t a wear issue, it is an "SD Cards Break easily" issue.
> 
> With all statements like that I would really like to hear at least the following about failed devices:
> 
> 1. brand and model of device that failed on you

Various brands. The most recent were SanDisk and Samsung.

> 2. the source (vendor) you got the device from

Microcenter or Amazon.

> 1. High grade Samsung 128GB 100MB/s (U3) MicroSD EVO Select;

The Samsung that failed after about six months (written to once, read maybe 100 times) was a 32GB EVOplus 80MB/s 20MB/s microSD. I don’t have the SanDisk one anymore, but it was also a 32GB with similar specs. Both decided one day they were 32MB storage devices. The SanDisk at least had the decency to do it when it was being formatted.

> 2. This one I do not consider the best, but it survived at least 6 years of use in car camera: Micro Center class 10 Micro SD (32 GB)

I tend not to buy store brands, but I think SanDisk makes the cards for Microcenter’s house brand.

> So, instead of generalizing, I would really like to hear the detailed information about _failed_ devises

Too many for me to have kept close track of. They generally fail faster than I expect, but some seem to last forever. When one fails I normally try a bit to recover it, then bin it and pull out another one.

-- 
Well I've seen the Heart of Darkness/Read the writing on the wall/and the
voice out in the desert/Was the voice out in the hall