H. Peter Anvin
· Msg 549 · kommentar
2011-08-03 21:25
Ärende: Abc80/Abc800 Kryoflux
Har registrerat för ett konto, men här är text för vad jag vet:
ABC80/800 floppy disks come in a few formats; the "standard" ones are
SSSD (80K), SSDD (160K), and DSQD (640K), with some third party drives
being DSDD (320K). The basic formatting parameters are:
Format Encoding Sector size Sectors/track Tracks
SSSD FM(?) 256 bytes 8 40
SSDD MFM 256 bytes 16 40
DSDD MFM 256 bytes 16 40 x2
DSQD MFM 256 bytes 16 80 x2
8" ? ? ? 77 x?
I am not fully sure how the sectors were numbered on the disks: they can
be read on a PC with the standard Linux floppy device driver by entering
appropriate parameters, but at least the SSDD disks that I happen to
have come out interleaved. This might mean there is interleaving on the
disks that the Linux device driver ignores, or it might mean that the
interleaving was done in software (firmware, actually, as the controller
had its own CPU.)
Filesystem details are another matter; they vary slightly depending on
ROM version (much to users' annoyance), but I can get you the basic
information if that matters as well.
-hpa
