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Questions tagged [sd-card]

Secure Digital (SD) cards are a widely used memory card format used by many technology brands brands in portable electronic devices such as digital cameras.

SD cards are 24mm x 32mm in size and have high transfer rates at low power consumption which makes them popular for battery powered devices.

SD cards are an improvement of the MultiMediaCard (MMC) and have in turn been improved as products termed SDHC (high capacity) and SDXC (extended capacity).

Smaller versions known as the miniSD card (20mm x 12.5mm) and microSD card (11mm x 15mm) also exist.

See also:

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Why is “/dev/rdisk” about 20 times faster than “/dev/disk” in Mac OS X

According to the rasbery pi documentation, You can load your OS to a flash card with either /dev/disk or /dev/rdisk. rdisk stands for raw disk. /dev/disk is a block level device, why would rdisk be 20 times faster? Using Mac OSX Note: In OS X…
spuder
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How can I intentionally break/corrupt a sector on an SD card?

I need to test the resilience of some read/write code for some embedded hardware. How might I sacrifice a few SD cards and break several known sectors for a controlled study? The only thing I can think of is to overwrite a single sector a few…
Gabe Krause
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What's the life expectancy of an SD card?

I have some SD cards that I use. Is there a limit to how many times I can write over them? If I leave information on a card, is there anything that can cause it to lose this information eventually (other than a magnetic field)? What's the preferred…
Yuval
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How to access an SD card from a virtual machine?

I want to format an SD card from my Linux virtual machine. I have a built-in SD card reader in my laptop. I tried using VirtualBox and VMware Player and installed Ubuntu 10.04 guest. None of them are showing the SD card reader as a device. I can…
Punit Soni
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How do you format a 2 GB SD card to FAT32 (preferably with Disk Utility)?

I've been looking around for a way to do this for a while, but I haven't been able to find the answer. I need to format my 2 GB SD card to FAT-32, but I don't see the option in Disk Utility. If I select the SD drive (Apple SDXC Reader Media) and go…
Matt Reynolds
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How to mount a multi-partition disk image in Linux?

I downloaded an raw SD card image that has two partitions. It caused some file system errors when I tried to dd it directly into an SD card. I am not sure if the card is defective or the image. Is there a way to examine this image without writing…
Atilla Filiz
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How to recover data from microSD card that cannot be read?

I am trying to help a friend who is very concerned that she has just lost all of the data on her 32GB SanDisk microSD card. I told her I would post this and see if anyone could offer help. Here are the details: The SanDisk microSD card is less than…
Amazon Dies In Darkness
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Choice of filesystem for GNU/Linux on an SD card

I have am embedded ARM-based system running on an SD card. It's currently Debian GNU/Linux using ext3 as filesystem. As I'm about to reinstall the system, I started wondering about changing to a more flash-friendly filesystem. I've heard about…
gspr
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On Windows 8 or 10, particularly on tablets with a permanently inserted SD card, is there a universal way to treat the card as a non-removable drive?

I have a tablet, a Surface Pro, and I have a micro SD card that is permanently inserted. I use it to store media files like music and video. Windows, recognizing that it is a removable drive, deletes files immediately instead of putting them into a…
user274391
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How do I repartition an SDHC card in Windows?

How do I repartition an SDHC card (4 GB or more)? Do I need third-part tools or Linux (a live CD solution would be OK)? In Windows' Disk Management the option Delete Partition is dimmed out: I can reformat the card as FAT32, copy files to and from…
Peter Mortensen
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6 answers

How to use Cygwin to copy an image from an SD memory card

Long story short, I'm working on a Windows 7 machine and I'd like to strip the image off an SD card (backing up the card from a Raspberry Pi). I'm trying to use Cygwin, but not having much success. Examining the /dev directory, it looks like my SD…
GrandAdmiral
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SSD, SD, eMMC, Raw NAND what are the differences?

so the underlying technology with SSD, eMMC, SD, USB Flash etc... is NAND flash correct? So is the difference between all of them just the way controllers are implemented? Or are the technologies different all together? From what I know, I think…
Alistair
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Why do some USB readers have issues to read large capacity SD cards?

I have noticed that with some USB readers (not to mention other media devices, such as digital cameras) there seems to be an upper limit to the amount of internal storage they can support. When I insert low capacity micro sd cards (16GB or less)…
Arash Howaida
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Why aren't SD card 'contacts' uniformly placed?

As you can see above, Some contacts seem to be longer than the rest. Also, on the SD card (2nd from top) the last one seems to be thinner and also closer to the seventh pin. Why not just uniformly place all contacts of same sizes at uniform…
undo
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Recover data from SD card

I have a 2 GB Kingston microSD card which is about three years old. I put it in a reader today in my Windows Vista computer, wrote a 32 MB file onto it, safely removed it, and then tried to read it elsewhere. Nothing. Putting it back in the Windows…
Paul Tarjan
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