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FGiordani
Joined: 25 Dec 2005 Posts: 4
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Block Length in MMC |
Posted: Thu Jan 19, 2006 12:15 pm |
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All MMC cards have 512 bytes block length only in one write/read cycle?? |
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Humberto
Joined: 08 Sep 2003 Posts: 1215 Location: Buenos Aires, La Reina del Plata
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Posted: Thu Jan 19, 2006 4:30 pm |
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Quote: |
All MMC cards have 512 bytes block length only in one write/read cycle??
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Reading and writting to an MMC is generally done in 512 byte blocks, however erasing
often can be done in much larger blocks. For example SanDisk and other vendors has a
NAND architecture with an Erase Block capability of (32) or (64) 512 byte blocks, depending
of the card capacity. That is, in order to re-write a single 512 byte block, all other blocks that
belong to the same Erase Block will be simultaneously erased and it will need to be rewritten.
Humberto |
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asmallri
Joined: 12 Aug 2004 Posts: 1634 Location: Perth, Australia
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Re: Block Length in MMC |
Posted: Thu Jan 19, 2006 6:57 pm |
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FGiordani wrote: | All MMC cards have 512 bytes block length only in one write/read cycle?? |
The default read block size is 512 bytes. The read block size is configurable via a command and can be anything from 1 to 512 bytes. The write block size is always 512 bytes and must start on a 512 byte boundary. _________________ Regards, Andrew
http://www.brushelectronics.com/software
Home of Ethernet, SD card and Encrypted Serial Bootloaders for PICs!! |
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