Re: Problem with 2GB card using USB SD card reader
Wolfgang Mües <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
Hi Jason, On Samstag, 4. August 2007, Jason LeBrun wrote: > I'm using a Kingston 2.0GB SD card with a unbranded card reader > (model number UCR-61). When I insert the card, it's detected as > device using 512-byte sector sizes This is correct. All SD and SDHC cards are using 512 Byte sector size. > , and therefore it only shows up with about 1GB. The card reader fails to compute the right sector count. The only thing you can do about it: buy a new card reader. (You should buy a reader which is also capable of using SDHC cards IMHO). > I've poked around the mailing list, and I've found that a few other > people have mentioned this problem, and the responses to date seems > to imply that it's a hardware combination problem rather than a > driver problem. It's a card reader problem. It's the same with ALL 2GByte SD cards. > I understand that one of the issues is that certain readers can not > properly handle 1024-byte block sizes 2 GByte cards report a sector size of 1024 bytes. The host (==the card reader) is assumed to calculate the SD card size with these 1024 bytes. For all I/O operations, the host is assumed to use 512 bytes. Your card reader fails to implement this "hack" - invented for 2GB SD cards - correctly. > , but I don't think this is the > case here. If I use the same reader-card combination on a Windows > machine, the card is recognized as a 2GB device. Hmmmm... I think Windows is using the information from the partitions to compute the size, not from the CSD. regards Wolfgang -- Das Leben kann nur rückwärts verstanden, muß aber vorwärts gelebt werden. ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel