Addressong Secure Digital (SD) > 16MB

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I was wondering if someone could explain how one accesses beyond 16MB
on an SD card if the CMD17 format that reads a block of data contains
only a 32-bit byte address?  It seems that would restrict one to only
the first 16MB of data which leaves me at a loss of how to access all
the data contained on a 32MB, 64MB, etc. SD card.


Re: Addressong Secure Digital (SD) > 16MB
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Um, doesn't 32 bits = 4,294,967,295 (4GB) of addressing?  Or maybe SD
cards use different math...  (24 bits = 16MB)

But it does raise a good question - I recall seeing a 2GB card listed
somewhere, and 4GB+ can't be too far behind.

(As an interesting aside, casual Christmastime testing shows that the
cheaper Lexar 1GB SD cards sold by Fry's / write 2x faster
than the "high-performance" SanDisk "Ultra" cards that cost 50% more.)


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