Hi all,
after i finally resurrected my BIGBOARD and I made ??the boot of the operating system
CP/M, are struggling with reading old diskettes. Before i comes out completely my mind in
the counting of all parameters to pass to the program 22disk, someone knows a
comprehensive guide on how to decode the disc formats? I am very close to the
identification of parameters, but frankly it is extremely stressful. I'll try to list
where I am keeping in mind that the format Bigboard 1 has 77 tracks x 26 sectors / track
each with 128byte single-density single-sided.
1) almost every disk CP/M in the first 2 tracks the format is 77 tracks x 26 sectors /
track each from 128byte.
2) then starts the data portion that would be double-sided and i need to remove from this
portion the sectors used for the FAT whose number is to be calculated as a function of the
total number of sectors to be managed;
3) i'm able to reconstruct the sequence of sectors on the disk for the first 2 tracks
with the CP/M and for the remain data area;
4) then takes over a parameter which is the allocation unit size that means how fields are
grouped together to determine the parameters DRM
5) the allocation unit size determines all the other parameters BSH, BLM, DSM
6) Finally, AL0 and AL0 that the 22disk's document did not clarify well to me.
SO: that it is a bit hard for me...
Is out there anyone who can help me?
Excuse for my poor english.
Enrico -Pisa - Italy