> Harold,
>=20
> It's the sector erases.
>=20
> Normally, an excellent way to reduce erase counts would be to write a bun=
ch
> of 0xFFs, use 0xFF or 0xFFFF as an end of record marker, and add records
> using writes only.
>=20
> I tested a few SD cards and I determined that they perform erases at ever=
y
> single write, no matter what data is written. I'm not clear off the top o=
f my
> head how I determined that, but I was quite convinced at the time. The
> behavior is probably vendor dependent and unreliable anyway.
>=20
> ... just one more way SD cards suck for embedded. It's a terrible standar=
d.

Isn't it just the way that NAND Flash works ???

I suspect you would find that USB Memory sticks do the same under the same =
test, for the same reason.



--=20
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