On Sun, Mar 13, 2011 at 1:00 PM, C. Scott Ananian <cscott@xxxxxxxxxx> wrote: > On Sun, Mar 13, 2011 at 8:57 AM, Andrei Warkentin <andreiw@xxxxxxxxxxxx> wrote: >> Sorry to butt in, I think I'm missing most of the context >> here....nevertheless... I'm curious, ignoring outer packaging and >> product names, if you look at cards with the "same" CID (i.e. same >> manfid/oemid/date/firmware and hw rev), do you get same performance >> characteristics? > > No. To elaborate: see bunnie's blog post (cited above) on how the CID is often forged or wrong. I've also personally witnessed a manufacturer's rep come to the factory floor to reprogram a compact flash card's internal microcontroller with new firmware. This did not update any externally visible information reported by the chip. I had to convince the manufacturer to leave their proprietary hardware on the factory floor in order to be able to verify that future units would have the correct firmware. (Granted, this was not an MMC unit, but I would be surprised if MMC vendors were significantly different in this regard.) If you've spent any time working with Chinese/Taiwanese OEMs, you will notice that version control methodologies are (in general) disappointingly lax. --scott -- ( http://cscott.net/ ) -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
