Sdxc?


Jourdy288

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http://www.anythingbutipod.com/archives/2009/01/next-generation-sdxc-details.php
Due to limitations on transfer speeds and file systems SD has gone though a few upgrades. The first know as simply SD maxed out at 2GB. SDHC allowed for larger memory access of 32GB. Now SDxc maxes out at a whopping 2TB which should hopefully hold us over for a few years. This new standard uses exFAT file system or sometimes called FAT64. In addition to larger capacities SDxc will allow for higher theoretical speeds of up to 300mbps as opposed to 104mbps of SDHC.

sdxc-graph.jpg


Does anybody think we should start using these, and if so, will they work in the Pandora?
 
There are a lot of questions about SDXC in the past

//edit: I did try to give you a link of the search results, but it didn't work. So I guess you have to type in those 4 characters by your own.
 
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I very much doubt that the Pandora can run the i/o lines to the sd card at 100Mhz (required for SDXC), so I'm guessing we'll only have SDHC speeds which is 200Mbps interface speed (25MB/sec) @ 50Mhz, using 4 parallel data lines. Taking the overhead and OS into account, I'll guess that gives us >= 10MB <= 20MB depending on processor load.

I don't know where they get 104Mbps from, but it seems like they are quoting SD specifications (interface speed 25Mhz) rather than SDHC (interface speed 50Mhz).
 
Enverex said:
What sort of speed is the SD card slot in the Pandora looking at realistically? Do you think it'll actually be somewhere between 10-20MB/s?
I'm guessing its possible, but I don't have a Pandora to check, and even then there is a lot of optimisation that could most likely be done.
 
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The Nokia N800 has been measured to 11-12MB/sec with the "48 MHz" patch.
 
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