[coreboot] useful hardware - dip8 to soic8 adapter

Urja Rannikko urjaman at gmail.com
Sat Jun 20 02:37:48 CEST 2009


On Sat, Jun 20, 2009 at 02:32, Peter Stuge<peter at stuge.se> wrote:

> Note that only MMC (the very old cards) use 1-bit SPI. Any newer card
> uses a wider interface, which means even more complex translation
> logic.

Although it doesnt matter, every SD card must support 1-bit SPI (by spec).

> And even if the translation state machine would be fast enough, if
> e.g. it runs off it's own clock at maybe 100MHz instead of whatever
> is on SPI, the consumer grade flash memory cards can themselves have
> longer response times than what is allowed by the mainboard SPI.
>
> MMC has unlimited response times, as an example. Ie. the card can
> take as long as it wants to respond, at least for writes.
>
> The cards can also have rather complex voltage requirements.

Complex = 3.3V? (depends on the card though)

> All in all, a ton of work, and even doubtful that it could succeed.
>

I tought of this for a while (after i sent that message) and, we'll i
doubt its not even possible directly, it would need an ASIC with some
serious caching to work, if possible.

-- 
urjaman




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