Sorry if I missed this elsewhere.

Questions on understanding Tracks/Sectors/Heads and LBA:

When MYIDE.ASM or MYIDEROM.ASM is first ran it reports info on the CF card 
including the Cylinder/Head/Sector counts for that card. Can I trust these 
values?

Are 'heads' taken into consideration in the code (CHS to LBA conversion)? 
Based on my review of the code and the comments it seems 'heads' are not 
taken into account.

>From my limited research (wikipedia) the data below shows how to map CHS to 
LBA; I've done some simple Excel work and the formula below works as 
expected for my small CF cards taking into account the reported CHS values 
from MYIDEROM.

CHS (cylinder/head/sector) tuples can be mapped to LBA address with the 
following formula:

[image: LBA=((C \times HPC) + H ) \times SPT + S -1]

·       C, H and S are the cylinder number, the head number, and the sector 
number

·       LBA is the logical block address

·       HPC is the maximum number of heads per cylinder (reported by disk 
drive, typically 16 for 28-bit LBA)

·       SPT is the maximum number of sectors per track (reported by disk 
drive, typically 63 for 28-bit LBA)

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