On Nov 6, 2006, at 4:43 PM, James Newton, Host wrote:

> My understanding was that the card /makers/ had to pay the fees not
> the card /users/. Are they seriously saying that if you make a
> device that uses their product (and therefore sells more of
> their product) that you have to pay them a fee?
>
Yes.  This came up when we were looking for a flash card format
smaller than CF.  You have to be a member ($2000/year) before you
can get the full specification.  And then $1000/year for a host
license.  Plus royalties, I think (maybe not for just hosts.)

http://en.wikipedia.org/wiki/SD_memory has a summary, although I
can't comment as to its accuracy.  More at
http://www.sdcard.org/licensing/hala.html, although exact terms
and requirements seem pretty well obscured...

You may want to check socket availability

> Huh? Where did you hear that doubt expressed? Everything I have read 
> says
> that the serial modes are required...

The previously mentioned ARM project has had trouble reading "some"
SD cards smaller than 2G, and is reported not to work with any cards
larger than 2G (it uses SPI mode exclusively, I believe.)  "serial" mode
is not entirely the same as SPI mode (apparently.)  According to the 
wiki
page, SPI mode is "options" on microSD.  YMMV.  Some of this may be mere
driver bugs.

> I wonder if you will be able to purchase any size MMC
> card. They don't seem to have that large an install base...

True.  I can't tell how many "SD" capable products will also talk to
MMC (I've got some RSMMC cards on order; perhaps I'll do experiments
in the half-dozen or so SD/MMC hosts I have.)

At the rate things are going, MMC may survive simply based on being
one of the few small flash formats without licensing requirements.

BillW
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