🚀 go-pugleaf

In article <1990Dec8.182707.28401@usenet.ins.cwru.edu>, trier@cwlim.INS.CWRU.Edu (Stephen C. Trier) writes:
> BIOS options exist to read 256-byte sectors.  When I initially got a C
> compiler for a PC, one of my first projects was to try to read an OS-9
> disk.  I was never able to get the transfer to work right.  (On the
> other hand, I hadn't got used to PC programming yet back then!)
> 
> So the answer is "yes, it's possible, at least in theory."
> 

I had problems getting absread and abswrite to work - things were not
where they were supposed to be.  I finally figured out that absread adn
abswrite refer to logical sectors which are calculated from the current
drive parameters which ------ here's the gotch had to be set by first
doing a dir on a disk formatted to the correct density!!!  I was writing
disks on my SUN at work and could not figure out why I could only get
chunks of them.  I finally wrote a little unix util which wrote a bunch
of sectors (sequential) to disk which contained in ASCII what sector it
was..  TC was getting blocks and skipping blocks.  Finally figured out
that the disk sort of defaults to 360K if it has not been set!.
biosread() and bioswrite() allow you access to the exact sector you want
but you have to fill in the head,track and sector number.

I have since (read the pax doc) found that that is how other people set
the density - have a blank disk formatted with dos at the correct density,
do a dir on it THEN use the drive as you see fit.  It works.


-- 
Mikey (yes "he likes it!")
=======================================================   Mike Fields
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