ATA/ATAPI using DMA: Difference between revisions
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That information is sent in an entirely separate way to the proper disk -- see below.)
The low dword is a
The next word is a
A byte count of 0 means 64K. The next word is reserved (should be 0) except for the MSB. If the MSB is set, that indicates that this PRD is the last entry in the PRDT, and the entire set of transfers is complete.
The data buffers cannot cross a 64K boundary, and must be contiguous in physical memory (ie. they can't be "virtual" data buffers).
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