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# Read Native Max LBA using C#

I'm trying to figure out how to read in the native max LBA using C#.  For example, if someone changes the max LBA of a drive, I want to be able to read the original max LBA set by the manufacturer of the drive.  Can anybody help me with this, or point me in the right direction?

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dev117
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Commented:
there are basically two kinds of LBA: 28 bit and 48 bit. Whether a drive supports either of those, depends on the drive's driver and sometimes BIOS settings. In older windows versions, the ATAPI driver had a setting for either of those, and it needs to be enabled to allow large LBA. Info on how to check and how to change that is here: http://support.microsoft.com/kb/303013

In the event you mean what the largest LBA number is that a drive allows, you can do a little calculation based on the absolute size of the drive. The sector size is usually 512 bytes on modern windows systems (you can check to be sure). The maximum LBA sector number is then essentially equal to the absolute size divided by 512.

In the event you mean to find what the maximum size can be of a drive when 28-bit or 48-bit LBA is on, it is simple. 28-bit can do 2^28 * 512 = 137,438,953,472, or 128 GB. 48-bit LBA can do 2^48 * 512 = 144,115,188,075,855,872 or 134,217,728 GB or 128 PB (petabytes).

-- Abel --
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Commented:
In addition, this may be of help to get the real size of a physical drive (the middle section in my post) which was also used to get the LBA size. It is in VB6 code, if you need help translating it to C# let me know: http://www.experts-exchange.com/Programming/Languages/Visual_Basic/Q_22825938.html
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