Author Topic: Sdhc Support In 2.6.23+?  (Read 6554 times)

nontrivial

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Sdhc Support In 2.6.23+?
« on: January 10, 2009, 11:54:00 am »
I poked around and couldn't find the answer, so please excuse if this is common knowledge. Is SDHC (secure digitial high capacity (AKA big honking SD cards)) supposed do be handled in the 2.6.23+ kernels?

James

utx

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Sdhc Support In 2.6.23+?
« Reply #1 on: January 10, 2009, 05:54:31 pm »
Quote from: nontrivial
Is SDHC (secure digitial high capacity (AKA big honking SD cards)) supposed do be handled in the 2.6.23+ kernels?

Yes, SDHC cards work with new kernels.

tovarish

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Sdhc Support In 2.6.23+?
« Reply #2 on: March 11, 2009, 12:49:19 pm »
is that also true for c860. The reason I'm asking is that I'm not sure if the hardware supports it. is there also a size limit like 4GB, 8GB etc.
tovarish
« Last Edit: March 11, 2009, 12:50:12 pm by tovarish »

utx

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Sdhc Support In 2.6.23+?
« Reply #3 on: March 11, 2009, 01:18:57 pm »
Quote from: tovarish
is that also true for c860. The reason I'm asking is that I'm not sure if the hardware supports it. is there also a size limit like 4GB, 8GB etc.
tovarish

The "HC" part of "SDHC" is purely a software issue. If your OS has a direct access to the SD (i. e. your SD slot is seen as mmcblk* and not sd*), then new kernels will support SDHC there.

There is one remaining issue: SDHC defines higher transfer rates. I think that all SDHC cards work at standard SD rate as well.

tovarish

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Sdhc Support In 2.6.23+?
« Reply #4 on: March 12, 2009, 04:56:54 am »
ah, that is good to know. I am off to buy a high capacity card...

thanks,
tovarish

utx

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Sdhc Support In 2.6.23+?
« Reply #5 on: March 12, 2009, 07:08:24 am »
Quote from: tovarish
ah, that is good to know. I am off to buy a high capacity card...

Just a note. There still may be compatibility problems of some cards. For example: I tested four A-Data cards (MMC 1GB, SD/USB Duo 2GB, SDHC 16GB, myUSB stick). All of them read data correctly, but sometimes don't write data on Zaurus but write operation returns OK (note that at least for two of them, the failure was reproducible on desktop Linux machine). Card from other manufacturers don't exhibit this bahavior.