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.
Thanks, Craig
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 / Outpost.com write 2x faster than the "high-performance" SanDisk "Ultra" cards that cost 50% more.)
Richard
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