Sdxc Rolling Out From Panasonic

[fischju2000]

http://www.engadget.com/2010/01/06/panasonic-shipping-first-sdxc-cards-next-month-for-ungodly-amoun/

Announced at CES, 48GB and 64GB cards for (of course) ungodly prices. Didn't think this really needed to be in the Pandora board.

With this news and no more developments, I don't think we will see SDHC cards going above 32GB. At least not as a frontline product, and not any time soon. Comparing where SSDs launched price-wise not too long ago, these could get reasonable in a year or two (sub $200?). The question becomes: Will any current devices, like the Pandora, be able to use them. Even at speeds limited to SDHC.

 

[pelrun]

There have been multiple threads about SDXC here, you could try looking them up.

I don't think anyone (outside the SD committee and the companies who have paid $$$ for the standard) knows yet whether SDXC has changed anything in SDHC beyond substituting ex-FAT instead of FAT16.

 

[fischju2000]

I've read all the threads. Here is more info about their SDXC roadmap: http://www.engadget.com/2010/01/08/panasonic-sdxc-cards-roadmap-and-lumix-camera-lineup-at-ces-2010/ - 1TB cards this year seems huge, I wouldn't bet on them. Or costing any kind of reasonable price.

 

[Xenu]

I've read all the threads. Here is more info about their SDXC roadmap: http://www.engadget.com/2010/01/08/panasonic-sdxc-cards-roadmap-and-lumix-camera-lineup-at-ces-2010/ - 1TB cards this year seems huge, I wouldn't bet on them. Or costing any kind of reasonable price.

Wow the prices are really high, not supricing though. The price will go down considerably in a few months. It will be really intresting to se if the sdxc-cards will work in Pandora. Imagine having 2x1TB cards. The Pandora would not only be the best portable gaming device it would be a great portable storage device as well.

 

[Chip]

1TB cards this year seems huge, I wouldn't bet on them.

You won't see them. Not for several years. According the the chart you linked, they won't have anything larger than 64GB until 2011, and anything beyond 128GB just goes off into the undetermined future. You have to remember that Panasonic isn't even shipping these cards yet, and nobody else has even announced them. There are only a handful of devices that will ship this year that will be SDXC compatible, and they're all very expensive. There is an absolutely enormous installed base for SDHC, and people are not going to run out and buy all new devices just because there is a new SD version. SDXC will be scarce for at least the next 12-18 months, and I wouldn't expect it to overtake SDHC in penetration for 2-3 years minimum.

In the meantime, many of those SDHC devices can (or could, with a minor firmware update) support SDHC cards above 32GB. We will definitely see 64GB SDHC cards in the next year or two, and possibly larger. The soft 4GB limit on the original SD standard didn't stop manufacturers from making larger cards, and the soft 32GB limit on SDHC won't either.

 

[pelrun]

Actually, it was a hard 2G limit in the original SD standard. Manufacturers managed to repurpose an (sort-of) unused bit in the card's descriptor block to push that up to 4G, but that was always only an iffy hack.

SDHC had a soft 32G, because that is all FAT32 can address. If SDXC is different enough in the hardware, you may see some >32G SDHC cards; but if SDXC is backwards-compatible enough then the manufacturers will just label all their big SDHC cards as SDXC instead.

I did find a tidbit that SDXC runs at 1.8V as opposed to 3.3V for SDHC, but I got the impression that the card only switches to 1.8V for the fastest transfer modes.

 

[Alex.]

At what point will these huge sizes become irrelevant?

I use 2GB cards for my GP2X and Wiz, and my computer has a 12GB hard drive. The card in my GP2X only has 20MB free though (after 3 years' worth of awesome homebrew), so I can see myself using 4GB or even 8GB cards instead. I feel that anything beyond that point would be wasted, either by sitting empty or by being full of bits I will never find the time to use, ever.

 

[fischju2000]

I haven't seen 64GB SDHC cards in any announcements or on roadmaps, the '1TB this year' line is from Engadget's post. These format advances are messy business.

 

[Chip]

Actually, it was a hard 2G limit in the original SD standard.
...
SDHC had a soft 32G, because that is all FAT32 can address.

Neither of these points are quite right. Both SD and SDHC are limited only by their ability to address blocks of memory. The SD association officially recognized SD cards up to 4GB, though compatibility was not guaranteed with older devices. SDHC cards are physically capable of addressing up to 2TB of storage, but the spec only states 32GB. There are unused address bits which would allow an SDHC card to address up to 2TB of data. The FAT32 file system is not the limiting factor - it goes up to 2TB as well. More details on Wikipedia here.

As for 1TB cards this year, that is either a misprint or a joke. 64GB cards are not even shipping yet. Card density will have to double four times to get to 1TB. That is a minimum of 3-5 years away.

 

[WizardStan]

I am almost absolutely positive that the article is mistaken. If you look at the graph, it has years on it. At the start of 2010, it shows 48 and 64 gig cards. That's what we're kind of looking at now. Their estimating 1TB cards at the end of 2011, not 2010, so we're pretty close to 2 years away from that estimate, and I wouldn't be surprised if that was more of an optimistic marketing department, but we shall see.

 

[Chip]

See the tilde after 2011? That is supposed to indicate "and so on". Everything beyond 128GB cards should be assumed to be set for "some point in the indefinite future". I'd be surprised if they even had 256GB cards out by the end of 2011.

 

[pelrun]

Both SD and SDHC are limited only by their ability to address blocks of memory. The SD association officially recognized SD cards up to 4GB, though compatibility was not guaranteed with older devices. *snip* The FAT32 file system is not the limiting factor - it goes up to 2TB as well.

Theoretically, yes, the SD standard had *a way* of getting to 4G, but it wasn't ever usable, because absolutely no SD card ever produced had a blocksize other than 512 - which is why they did away with multiple blocksize support in SDHC. The only way to get to 4G then was to steal extra bits from the blocksize descriptor and use them to augment the number of blocks descriptor - i.e. an iffy hack. I've patched binary-only SD card drivers to support those cards in the past, so I know

I know about the SDHC situation, which is why I called it a soft limit - the bits were there to go up to 2TB from the start. My memory about FAT32 is obviously wrong though - and I'm definitely glad

 

[Squidge]

I did find a tidbit that SDXC runs at 1.8V as opposed to 3.3V for SDHC, but I got the impression that the card only switches to 1.8V for the fastest transfer modes.

That would be logical. 1.8V signalling @ 100Mhz is fairly typical. Its amazing how SD cards have progressed over the years, and are now as fast as some RAM during transfers.

Theoretically, yes, the SD standard had *a way* of getting to 4G, but it wasn't ever usable, because absolutely no SD card ever produced had a blocksize other than 512

Actually, thats wrong. The maximum size of a card with a 512 byte blocksize is 1GB. The way of calculating the card size on SDSC is 1 + 12-bit number (so 4095 max) * 512 (card size multiplier - could be less, but never more) * Block size, so:

4096 * 512 * 512 = 1GB.
4096 * 512 * 1024 = 2GB.
4096 * 512 * 2048 = 4GB.

Very few cards had a 2KB block size, some hack other fields to reach 4GB, but the result is very limited support.

It always seemed like the card had a 512 byte block size because they had a command SET_BLOCKLEN, which allowed you to state how much data to transfer, and you could pass the byte to start on to the read and write commands. Since the smallest block size is 512, and a FAT sector size is also 512 (lets leave out clusters here), it made sense to use that value. If you detected a 2GB card, you could quite happily read in 1KB blocks rather than 512, but since the FAT sector size was still 512 (and the fact you can use READ_MULTIBLOCK), it would be a pointless exercise.

For SDHC, they simply dropped this "start reading from any byte" and changed it to "start reading on a 512 byte block number". This immediately changes the addressable space from 4GB to 4GB*512 = 2TB.

 

[pelrun]

Okay, okay, it was a couple of years ago I did the actual work, so my memory is quite a bit faulty, so I checked my notes.

...I was arguing the point in this space, but I realised it's only a subtle difference to what you were describing, and the whole argument doesn't really matter anymore Lets just say the code I hacked originally did it the absolute 'official' way with larger blocks, and just barfed on anything that required the larger block sizes, so I munged the code to use 512 blocksizes always.