MicroSD

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(==External links==)
(Importent features)
 
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A list of supported cards can be found at [[Supported microSD cards]].
 
A list of supported cards can be found at [[Supported microSD cards]].
  
==Importent features==
+
==Important features==
Importent note: [http://en.wikipedia.org/wiki/Wear_levelling Wear-leveling] and ECC error correction and detection is not part of the SD card specification (version 2.0 SDHC), so please check for yourself that the SD(HC)-card support and use:
+
Important note: [http://en.wikipedia.org/wiki/Wear_levelling Wear-leveling] and ECC error correction and detection is not part of the SD card specification (version 2.0 SDHC), so please check for yourself that the SD(HC)-card support and use:
 
*built-in ECC error correction and detection
 
*built-in ECC error correction and detection
 
*Wear Leveling technology
 
*Wear Leveling technology
 
If the manufacturer advertises the card with e.g. 1,000,000 hours [http://en.wikipedia.org/wiki/Mean_time_between_failures MTBF], it might be a strong indication that the above features are used.
 
If the manufacturer advertises the card with e.g. 1,000,000 hours [http://en.wikipedia.org/wiki/Mean_time_between_failures MTBF], it might be a strong indication that the above features are used.
  
Other importent specifications are:
+
Other important specifications are:
 
*Low power consumption
 
*Low power consumption
 
*Number of insertions the card endures - 10,000 seems to be good quality.
 
*Number of insertions the card endures - 10,000 seems to be good quality.
 
*Total I/O operations per second
 
*Total I/O operations per second
 +
 +
==Use==
 +
*A log-structured file system (e.g. [[NILFS2]]) when available, ought to be a good choice because of the continuous snapshotting.
  
 
==References==
 
==References==
Line 22: Line 25:
  
 
==External links==
 
==External links==
*A log-structured file system (e.g. [[NILFS2]]) ought to be the best for flash cards: [http://www.sunhelp.org/pipermail/geeks/2008-February/061492.html 2008 (geeks) Flash wear leveling] Quote: "...We tested several file systems (ext2/3, xfs, reiserfs, FAT, ...) and finaly gave up...and developed an application speciffic log structured file system in userland..."
 
 
*MicroSD(HC) flash cards can be tested via a USB flash adaptor and H2testw. Please backup your data before testing: [http://sosfakeflash.wordpress.com/2008/09/02/h2testw-14-gold-standard-in-detecting-usb-counterfeit-drives/ September 2, 2008, sosfakeflash.wordpress.com: H2testw 1.4 – Gold Standard In Detecting USB Counterfeit Drives], [http://www.bloggersbase.com/computers/h2testw-fix-usb/ bloggersbase.com: H2testw - Fix Your USB!] Quote: "...H2testw was developed to test USB sticks for various kinds of errors. It can also be used for any other storage media like memory cards, internal and external hard drives and even network volumes...", [http://www.heise.de/software/download/h2testw/50539 H2testw 1.4]
 
*MicroSD(HC) flash cards can be tested via a USB flash adaptor and H2testw. Please backup your data before testing: [http://sosfakeflash.wordpress.com/2008/09/02/h2testw-14-gold-standard-in-detecting-usb-counterfeit-drives/ September 2, 2008, sosfakeflash.wordpress.com: H2testw 1.4 – Gold Standard In Detecting USB Counterfeit Drives], [http://www.bloggersbase.com/computers/h2testw-fix-usb/ bloggersbase.com: H2testw - Fix Your USB!] Quote: "...H2testw was developed to test USB sticks for various kinds of errors. It can also be used for any other storage media like memory cards, internal and external hard drives and even network volumes...", [http://www.heise.de/software/download/h2testw/50539 H2testw 1.4]
  
 
[[Category:MicroSD| ]]
 
[[Category:MicroSD| ]]

Latest revision as of 13:43, 10 June 2010

microSD is the format of the removable flash memory cards used in Neo 1973 and Neo Freerunner devices. Additionally the Neo Freerunner support microSDHC.

For more informations about this format see microSD on Wikipedia.

A list of supported cards can be found at Supported microSD cards.

Contents

[edit] Important features

Important note: Wear-leveling and ECC error correction and detection is not part of the SD card specification (version 2.0 SDHC), so please check for yourself that the SD(HC)-card support and use:

  • built-in ECC error correction and detection
  • Wear Leveling technology

If the manufacturer advertises the card with e.g. 1,000,000 hours MTBF, it might be a strong indication that the above features are used.

Other important specifications are:

  • Low power consumption
  • Number of insertions the card endures - 10,000 seems to be good quality.
  • Total I/O operations per second

[edit] Use

  • A log-structured file system (e.g. NILFS2) when available, ought to be a good choice because of the continuous snapshotting.

[edit] References

[edit] External links

Personal tools

microSD is the format of the removable flash memory cards used in Neo 1973 and Neo Freerunner devices. Additionally the Neo Freerunner support microSDHC.

For more informations about this format see microSD on Wikipedia.

A list of supported cards can be found at Supported microSD cards.

Importent features

Importent note: Wear-leveling and ECC error correction and detection is not part of the SD card specification (version 2.0 SDHC), so please check for yourself that the SD(HC)-card support and use:

  • built-in ECC error correction and detection
  • Wear Leveling technology

If the manufacturer advertises the card with e.g. 1,000,000 hours MTBF, it might be a strong indication that the above features are used.

Other importent specifications are:

  • Low power consumption
  • Number of insertions the card endures - 10,000 seems to be good quality.
  • Total I/O operations per second

References

External links