Maximum size SDHC card that can be used?


I say go with a Class 6 16 GB card, they seem to be the best price point now. If you have way too much money, go with one of those $200 32GB cards with ludicrous read write speeds...(I am not responsible for anything that goes wrong by following my advice).
 
lol well the one in the pandora store is £70 - that's pretty good isn't it? if i can find one for a bit cheaper i'll probably stick with the 32GB ones (save me having to change cards (im want a lot of PSX games lol >.<))
 
Cheapest I've found for a 32gb (Class 4) is $135 :eek: :wacko:

I'll stick with dual 16gb's for now
 
if thats the case, then we dont really have a choice lol - would be rediculous to spend that much more... is there anyway to compress PSX roms or something?
 
I just settled for the 16 GB card with my Pandora purchase because I don't even own enough PSX games to fill the card up :(
 
crimsonnight said:
if thats the case, then we dont really have a choice lol - would be rediculous to spend that much more... is there anyway to compress PSX roms or something?

Normally there is, but it does not work with every game. I think the Final Fantasy 7 disk's can be compressed from 700MB/disk to 530MB/disk.

There is a list i noticed googling the topic at: List of titles & there compression
FFVII DISC 1 712 Mo ----> 529 Mo
FFVII DISC 2 698 Mo ----> 512 Mo
FFVII DISC 3 629 Mo ----> 464 Mo

In other words, compressing your backups, results in a nice save of 150 to 450mb / disk. Do that times x games your planning on carrying and that can add up to 2 or 2.5* more games on the same storage card. So yea, compression + a large SD card results in one hell of a mobile setup. We are talking about PSX. Older emulated games like SNES, etc are ofcourse a fraction of that size. A few 100 games on a dual 32GB setups looks possible. ;-)
 
awesomonay! thanks for the info, gotta save this topic for when it comes out - how exactly do u compress the ISOs then - could u please link me to the program?
 
ok thanks, i'll save this thread, and just confirm it's compatible when the emulator's released ^^
 
the_darkside_986 said:
I just settled for the 16 GB card with my Pandora purchase because I don't even own enough PSX games to fill the card up :(

I'm with you, I don't see myself storing thousands of videos/roms on the pandora, so 16 gigs should be more than enough. I was tempted in fact, to just get a 8gb card because I thought it would suffice, but I decided against it as it is just a bit more for double the storage.

By the way, why did you steal my sig? :huh:
 
Chip said:
The current cap or 32GB exists for two reasons.

The first is technological - Facilities do not yet exist to manufacture larger cards. This hurdle will obviously be overcome in the near future.

The second is merely bureaucratic - The SD Association likes to keep a tight leash on their standards. The thing with standards is that they only work if they're standard. Once one of the flash memory companies figures out a good way to fit 64GB of storage onto an SD card, the SDA will set a standard based on that. That way all cards and readers will work together.

For the Pandora, compatibility probably won't require anything more than a driver update, if that.

Actually, I am fairly certain that these are not the correct reasons for the cap. Though I agree that a part of it is bureaucratic in nature. So, I will give you the abridged version of SD filesize limits.

SD v1.x (any non SDHC card) - maximum filesize 2G/4G
One of the reasons why original sd cards had their maximum filesize capped was because they used fat16 formatting by default. Which caps at 2G normally or at 4G if it used 64k clusters (however this feature was not widely supported).

SD v2.x (SDHC)
A noticeable change for the next revision was that the default filesystem was changed to fat32 aka vfat which caps out at around 2TB I think. However, windows formatting utilities do not let you create fat32 partitions beyond 32G in size because of how inefficiently they work at large sizes. So technically you could call this portion the bureaucratic reason if you wanted.

And here is the non bureaucratic reason why the file system limits as are as they are.
"
Devices that use SD cards identify the card by requesting a 128-bit identification string from the card. For standard-capacity SD cards, 12 of the bits are used to identify the number of memory clusters (ranging from 1 to 4096) and 3 of the bits are used to identify the number of blocks per cluster (which decode to 4, 8, 16, 32, 64, 128, 256 or 512 blocks per cluster).

In older 1.x implementations the standard capacity block was exactly 512 bytes. This gives 4096 x 512 x 512 = 1 gigabyte of storage memory. A later revision of the 1.x standard allowed a 4-bit field to indicate 1024 or 2048 bytes per block instead, yielding more than 1 gigabyte of memory storage. Devices designed before this change may incorrectly identify such cards, usually by misidentifying a card with lower capacity than is the case by assuming 512 bytes per block rather than 1024 or 2048.

For the new SDHC high capacity card (2.0) implementation, 22 bits of the identification string are used to indicate the memory size in increments of 512 KBytes. Currently 16 of the 22 bits are allowed to be used, giving a maximum size of 32 GB. All SDHC 4-GB and larger cards must be 2.0 implementations. Two bits that were previously reserved and fixed at 0 are now used for identifying the type of card, 0=standard, 1=HC, 2=reserved, 3=reserved. Non-HC devices are not programmed to read this code and therefore cannot correctly read the identification of the card.
"
-The preceding excerpt was snipped from wikipedia article on (Secure Digital)
 
pseudomind said:
However, windows formatting utilities do not let you create fat32 partitions beyond 32G in size because of how inefficiently they work at large sizes.
Shhh! Don't say that too loudly. My FAT32 formatted 1TB WD hard drive might hear you and implode under the realization of the impossibility of its existence. :lol: FAT32 isn't the most effecient file system around (the drive loses about 7% of its capacity to overhead), but it mustn't be taboo, as my drive came formatted that way from the factory. If I had to take a guess as to why, I'd say it's to keep cross-platform compatibility. FAT16 and FAT32 are the only file systems that work out-of-the-box on PC, Mac and Linux. I'd wager that when 64GB SDHC cards appear, they'll use FAT32 as well for the same reason.

For the new SDHC high capacity card (2.0) implementation, 22 bits of the identification string are used to indicate the memory size in increments of 512 KBytes. Currently 16 of the 22 bits are allowed to be used, giving a maximum size of 32 GB.
In other words, the current standard cannot address more than 32GB of storage. Once the SDA decides which of the six remaining bits will indicate a 64GB card, they will publish the new standard, and the game is on. At worst, the Pandora's SDHC driver may have to be updated to account for this new bit, so that it may address the additional storage properly.

...Which is pretty much what I said in the first place. :D
 
Shhh! Don't say that too loudly. My FAT32 formatted 1TB WD hard drive might hear you and implode under the realization of the impossibility of its existence. :lol: FAT32 isn't the most effecient file system around (the drive loses about 7% of its capacity to overhead), but it mustn't be taboo, as my drive came formatted that way from the factory. If I had to take a guess as to why, I'd say it's to keep cross-platform compatibility. FAT16 and FAT32 are the only file systems that work out-of-the-box on PC, Mac and Linux. I'd wager that when 64GB SDHC cards appear, they'll use FAT32 as well for the same reason.

Drives can be formatted by tools other than the Windows ones available to most users. And as you note, it works just fine with Windows when formatted elsewhere. You're right about cross-platform compatibility, but in the wrong direction.

I very much doubt they care about Linux -- however, it's important to remember that SD had to be readable by PC, Mac, and the billion devices that support SD. Cameras, phones, Nintendo DS and so on. FAT32/vfat is the only system that is easily implemented on random crappy microcontrollers and Windows. I dare say Windows is the limiting factor here, which supports only FAT and NTFS out of the box. NTFS is supported on Linux, both in kernel and userspace tools (donno about mac). But NTFS kinda sucks on embedded systems. I have to expect that very soon SD will have to define their own filesystem if they want to push much farther. Any technology they pick will have to be acceptable to both Microsoft and embedded systems, which are kind of at odds with one another ;)
 
Just a word of warning for anyone wanting a large SDHC card in the UK - DON'T BUY FROM THE HIGH STREET! The major electronics stores (maplins, currys, comet, etc) charge ridiculous prices for them. A 4gb SDHC card at maplins was £40 (!) and the 16GB size (which wasn't in store) was £100. Not only were they 4x the online price, they were Class 2! Complete rip-off.
 
Truekaiser said:
I buy all my computer parts from new egg..
Newegg FTW

I hate Fat32 though, it would be good for the Pandora. I have a lot of HD movies and with Fat32's 4gb file size limit, it just doesn't suffice. Every WD harddrive I get is fat32, but it goes right to ext3 or ntfs depending.
 
Well in regards to one of the sub topic's brought up dealing with PSX games...I'd actually hope the Emu's would support Mame style CHD's...as a bases for CD\DVD's.

Not as good of compression as DaemonTools compressed MDS\MDF's...but at least an open standard.
 
Nothing's stopping me from using a filesystem without such flaws -- like XFS -- on my SDHC card. I'll probably end up transferring things to it from the desktop over wifi and NFS or FTP anyway, and linux will handle the filesystems.

FAT32 is indeed one of the reasons they're holding back on larger than 32GB cards. Windows, as mentioned before, insists on formatting volumes larger than 32 GB as NTFS without using command-line tools. And since having the Windows masses use a command line tool is tabboo, the card manufacturers will probably have to offer their own format utilities, or make Microsoft offer a windows update which allows their tool to perform larger FAT32 formats on USB devices. It's a mess.

Another reason, more practical to a linux end user is price. The largest economical size for most users is still 16GB. The 32GB cards are still very expensive, and anythign above would be ridiculous at this point.
 
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