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A Fun New Challenge (For me anyway)

December 30th, 2009, 0:32

First off, I want to say thanks to all of the helpful people here. As I am reading through the ATA spec, I had a few questions I was hoping on of you all mighty gurus could help with.
Refering to the attached picture and related to the Read Sectors command, am I right by saying

that
1x2 - 1x3 is the number of sectors (744)
1x4 - 1x6 is the starting sector (196832)

Or point to a specific reference regarding the offsets?
Thanks
Shawn

Capture.JPG

Re: A Fun New Challenge (For me anyway)

December 30th, 2009, 1:16

So as I experiment further, I am finding that x2 is the count and 3/4/5 are LBA. Sound right?

Re: A Fun New Challenge (For me anyway)

December 30th, 2009, 2:55

2 is length
3,4,5 and 4 bits of 6 are LBA

Re: A Fun New Challenge (For me anyway)

December 30th, 2009, 10:08

so x1 is specifically used for what? The words are identified as an offset from 1? where does 6 come into play? I promise this will be the last question on "this" subject. Thanks again for eveything!
Shawn

Re: A Fun New Challenge (For me anyway)

December 30th, 2009, 10:20

x1 is the number of sectors to read.

3,4,5,6 are the start LBA

Look at the ATA specs .. They will explain the registers in all modes, CHS, LBA and LBA48

Re: A Fun New Challenge (For me anyway)

December 30th, 2009, 10:37

scratchy wrote:x1 is the number of sectors to read.

3,4,5,6 are the start LBA

Look at the ATA specs .. They will explain the registers in all modes, CHS, LBA and LBA48


Correction - I was ahead of myself.

1 is the Features Register.. 2 is the sector count register :)
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