how to get some values for LBA <-> CHS conversion?

From: lallous (lallous_at_lgwm.org)
Date: 05/26/04 

Date: Wed, 26 May 2004 17:59:27 +0000 (UTC)

Hello

I am trying to apply this formula (found @
http://encyclopedia.thefreedictionary.com/CHS%20conversion):

[quote]
>>From CHS to LBA
The equation to convert from CHS to LBA follows:

 LBA = ( ( CYL * HPC + HEAD ) * SPT ) + SECT - 1

Where:

 LBA: linear base address of the block
 CYL: value of the cylinder CHS coordinate
 HPC: number of heads per cylinder for the disk
 HEAD: value of the head CHS coordinate
 SPT: number of sectors per track for the disk
 SECT: value of the sector CHS coordinate
[/quote]

I have read the partition table and got these values: CYL, HEAD, SECT; how
can I get the other missing variables (SPT & HPC) ? 

--
Elias

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