Its not about software , Its about how hardware implement a stack / spec. You can read this first , to understand how a sdxc stack runs failed on a sdhc host
https://www.sdcard.org/downloads/pls/simplified_specs/part1_410.pdf 2014-07-23 12:25 GMT+08:00 Eric Fort <[email protected]>: > so that sounds like a software issue not a hardware issue. When I refer > to hardware I really mean the electrical signaling on the interface to the > host. only thing I can think of there is some subsystem in an soc ends up > being too smart for it's own good in trying to handle those commands such > that the host never actually sees the commands being sent/received on the > interface. cmd length sounds like a linux kernel driver issue. > > Eric > > > On Tue, Jul 22, 2014 at 9:14 PM, liyaoshi <[email protected]> wrote: > >> Its about sdhc cmd format ，some sdhc cmd/resp will get different length >> from sdxc >> >> >> 2014-07-23 11:03 GMT+08:00 Eric Fort <[email protected]>: >> >> so one is completely unable to reformat an SDXC card with another >>> filesystem type such as ext3? Is it simply a filesystem issue or are there >>> hardware differences to be overcome? >>> >>> Eric >>> >>> >>> On Mon, Jul 21, 2014 at 8:40 AM, Robert Nelson <[email protected]> >>> wrote: >>> >>>> On Mon, Jul 21, 2014 at 10:34 AM, Eric Fort <[email protected]> >>>> wrote: >>>> > so can someone link to something definitive stating that for the >>>> beagle bone >>>> > (black) 32GB SDHC is the biggest card supported (assuming this is >>>> correct)? >>>> >>>> From: >>>> http://en.wikipedia.org/wiki/Secure_Digital#SDXC >>>> >>>> The Secure Digital eXtended Capacity (SDXC) format, announced in >>>> January 2009 and defined in Version 3.01 of the SD specification, >>>> supports cards up to 2 TB (2048 GB), compared to a limit of 32 GB for >>>> SDHC cards in the SD 2.0 specification. SDXC adopts Microsoft's exFAT >>>> file system as a mandatory feature. >>>> >>>> aka: >>>> microSDHC 32GB is your limit.. >>>> >>>> Regards, >>>> >>>> -- >>>> Robert Nelson >>>> http://www.rcn-ee.com/ >>>> >>>> -- >>>> For more options, visit http://beagleboard.org/discuss >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "BeagleBoard" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
