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Ruud Baltissen wrote: > Hallo allemaal, Lo Ruud. > 1) What I need is a conversion from "Track/Head/Sector" to a lineair number. Exactly what 'type' of THS are you dealing with? Is it a 1541-ish type of disk (for a diskimage, for example) with a variable number of sectors, or do you want to convert 'IDE' THS (with a fixed geometry) back and from a logical block address? (In that case, you may want to use LBA adressing instead - most disks > 500MB probably support that. No conversion required). > And vica versa of course. > > Information you need: > HDTRACKL = Low byte number of tracks on harddisk > HDTRACKH = High byte number of tracks on harddisk > HDHEADS = number of heads > HDSECT = number of sectors on a track. It *seems* like you want to have a fixed geometry, in which case it's reasonably simple: block(t,h,s)= t * HDHEADS * HDSECT + h * HDSECT + s or block(t,h,s)= (t * HDHEADS + h ) * HDSECT + s (Saves one multiplication) THe other way 'round is only slightly more complicated. It is helpful if you have a 'cylinder'-step. s = block MOD HDSECT c = block \ HDSECT h = c MOD HDHEADS t = c \ HDHEADS with 'MOD' being the modulo (or the 'remainder' of a division), \ being an integer division. Ofcourse you can rewrite this to get rid of the MOD by doing something like c = block \ HDSECT s = block - c*HDSECT t = c \ HDHEADS h = c - t*HDHEADS The NRTRACKS is not required at all. -- Martijn van Buul - Pino@dohd.org - http://www.stack.nl/~martijnb/ Geek code: G-- - Visit OuterSpace: mud.stack.nl 3333 Kees J. Bot: The sum of CPU power and user brain power is a constant. Message was sent through the cbm-hackers mailing list

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