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Re: [OCLUG-Tech] how to determine the *usable* size of an SD card?

  • Subject: Re: [OCLUG-Tech] how to determine the *usable* size of an SD card?
  • From: Woogie <woogie [ at ] gmail [ dot ] com>
  • Date: Thu, 19 Jan 2012 15:09:10 -0500
I thought the fallout of the infamous lawsuits against the HDD
manufacturers was that "8Gb" and "1Tb" as labels on storage media were
understood to mean 8x10^9 and 1x10^12, respectively, by the courts.
Which is why the "proper" SI notation for file sizes as MiB and GiB is
showing up more often these days.

On Thu, Jan 19, 2012 at 3:02 PM, Robert P. J. Day <rpjday [ at ] crashcourse [ dot ] ca> wrote:
> On Thu, 19 Jan 2012, Singer X.J. Wang wrote:
>
>> That's a deviation of less then 0.5%.. that's not that bad in most industries..
>>
>> S
>>
>> On Thu, Jan 19, 2012 at 14:48, Robert P. J. Day <rpjday [ at ] crashcourse [ dot ] ca> wrote:
>>
>>        over the last day on the beagleboard list, there was an animated
>>       discussion that touched on the fact that some "dd" copies to SD cards
>>       was failing since the actual capacity of the SD card was noticeably
>>       less than advertised.  as in, trying to write a 4G image to an
>>       allegedly 4G SD card failed, "no space left on device".
>>
>>        is there a utility in linux that will tell me that *real* capacity
>>       of an SD card if i pop it into the SD slot?  if i write an image to an
>>       allegedly 8G micro SD card and pop it into my beagleboard, and stop in
>>       u-boot, what i can do is:
>>
>>       # mmcinfo
>>       Device: OMAP SD/MMC
>>       Manufacturer ID: 27
>>       OEM: 5048
>>       Name: SD08G
>>       Tran Speed: 25000000
>>       Rd Block Len: 512
>>       SD version 2.0
>>       High Capacity: Yes
>>       Capacity: 7969177600     <--- AHA!
>>       Bus Width: 4-bit
>>       #
>>
>>        that's *clearly* less than a true 8G.  is there a way to see that in
>>       linux?  thanks.
>
>  huh?  8G is officially 8589934592.  the value above is a full 8%
> smaller.
>
> rday
>
> --
>
> ========================================================================
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>
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