20060926

SD 2.0 and SDHC cards (also MMC >4GB)

I'm looking for some information and/or some hardware in this installment.

Today, I noticed that the SD 2.0 specification has been released by the SD association. The simplified version, that is. The full spec, like the 1.x versions, doesn't include the security features. Looks like there's a number of new 'host' requirements. I can't yet deside if these requirements are at a hardware or a software level yet...

So, if someone wants to purcahse me a 8GB SD or MMC card, I'll be happy to make it work.

I've started in earnest on the mmc layer. It should be done shortly. The qdmmc driver that Bernd wrote lead the way, but making commands properly be async was difficult in its structure, so I've decided to try it with the proper layering instead.

6 comments:

Edward Leron said...

So, are you saying that you can get an SDHC card working on an SD device, like a samsung sch i730?

http://pdaphonehome.com/forums/samsung-i730-i830-i830w/80943-8-gb-sd-card.html

Warner Losh said...

SDHC cards need special support in the system software that interacts with them. It may be possible to retrofit some bridges for SDHC support that didn't support it from the get go. And it may not. It depends on the bridge. My reading of the SD 2.0 standard might be in error.

For embedded devices like the phone you pointed me at, you may be SOL unless your vendor provides new firmware and the phone has a SD host adapter that is flexible enough for the SDHC command set.

Dominick said...

We know Samsung and/or Verizon is not going to release a firmware for SDHC to work on the i730. Is there a way to find out if you could get it working for the i730?

Warner Losh said...

Since the i730 is a Windows CE phone, I can't help you. I don't know the underlying hardware. Since it is a Windows CE machine, and since there's content protection in the sekret part of the spec, it is unlikely that I can help at all.

Dominick said...

That sucks..Ok thanks. I found out via testing with someone at Pdaphonehome that SDHC cannot work at all due to hardware limitations in the reader..The best thing we with Samsung i730s can do is get a 6GB MicroSD Card with a MicroSD to SD adapter, wait till 8GBs and up come out for it, or wait for an 8GB-32GB MMCPro SD Card. Thanks.

Junkie2100 said...

it took me quite some time but i have found a way to read a full 8gb+ sdhc card on the i730. you need the sdhc drivers for c550 and n560 by GreateVK and 777-Team. they work flawlessly and i can say that my lexar 8gb card is fully readable writeable and even displays the correct amount of total and free space. months of work finally paid off for me and hopefully by reading this other wm5 device users will be able to learn from my experience