Path: utzoo!utgpu!water!watmath!clyde!att!rutgers!ucsd!ucbvax!decwrl!sun!pitstop!sundc!seismo!uunet!mcvax!enea!chalmers!cthce!hacke0!d7pernb
From: d7pernb@hacke0.UUCP (Nicklas Pernblad)
Newsgroups: comp.sys.amiga.tech
Subject: A2090 questions
Message-ID: <191@hacke0.UUCP>
Date: 25 Jun 88 12:27:18 GMT
Reply-To: d7pernb@hacke0.UUCP (Nicklas Pernblad)
Organization: Chalmers Univ. of Technology, Gothenburg, Sweden
Lines: 18

I recently got a Seagate ST4144R hard disk for my A2090 controller. The
hard disk has a MFM formatted capacity of 80MB, but since it has 9 heads
and 2090 only can handle 8, the maximum storage you can expect is 71MB.
I was able to successfully format all 1024 cylinders and info revealed
69MB free. But after a reboot or loadwb the hard disk would go into an
endless validating loop. After prep-ing the drive with decreasing number
of cylinders, 777 seemed to be the highest reliable value giving me 52MB.
Is this a limit in AmigaDOS, 2090 or in my knowledge? And why a 52MB limit,
I could understand 32, 64, 128MB...?

A question to some CBM technical expert: The A500/A2000 Technical Reference
Manual (page 160) documents a pin on the 2090 called 'Write Protected'. I
thought this would be a neat way to keep any virus' greedy hands off my hard
disk. But after a few experiments I discovered that the pin does not seem
to be used at all. Is this a correct observation? Is there any other way to
write protect the hard disk?

Nicklas Pernblad