22 Jan
2003
22 Jan
'03
4:38 a.m.
Quoting pete(a)dunnington.u-net.com:
On Jan 18, 16:16, Philip Pemberton wrote:
One has to be very careful with the formatting - there where several different
FS formats - some with varying compatibility. (Talking about the file system
side here) The Master welcome disc used ADFS which was slightly more advanced
than the more common DFS that was used on the earlier Acorns.
I do have some scribbled documents which describe Acorn DFS in enough detail,
plus some sample code which will extract and create disc images which I can
send on (IIRC the code is actually on the web on one of the Acorn web sites - I
can't remember which one though!)
dave
Finally, does anyone know how some discs were
formatted so they were
compatible with 40-track and 80-track disc drives?
The way Acorn did that with
things like the Master 128 Welcome Disc was to
make all the directory entries (on track 0) point to tracks between 5 and
9, and 20 and 39. Track 20 on a 48-tpi drive is where track 40 would be on
a 96-tpi drive: