Path: utzoo!mnetor!uunet!mcvax!ukc!its63b!hwcs!neil
From: neil@cs.hw.ac.uk (Neil Forsyth)
Newsgroups: comp.sys.atari.st
Subject: Failing Disk Drive & Strange TPA pointer
Message-ID: <1606@brahma.cs.hw.ac.uk>
Date: 22 Dec 87 09:36:49 GMT
Organization: Computer Science, Heriot-Watt U., Scotland
Lines: 43
Keywords: Big Help & Little Help


Boo hoo the disk drive on my 1040ST is not working. I know it is the drive
because I have swapped it in other machines and the problem moved with the
drive. The symptoms are strange in that it reads every track on a disk fine
but has trouble writing. I say trouble because sometime it formats a track
ok sometimes not, but never a whole disk. I had a look at a track it had tried
to format and found corruption (gap bytes inconsistant & data damaged ie $E5
corrupted.) If I can't fix this drive I will have to buy a replacement and
that will kill my slim chance of being able to afford a hard drive.
I phoned a company that upgrades the internal SS drive in a 520STFM to DS and
asked if the same drive could be fitted inside a 1040. They said no, which I
think is pretty strange since I thought (as most do) that the 520STFM was
just a 1040 with a lesser drive and some RAM missing. Has anyone else put a
different drive in their 1040 or repaired the original one? 
If so please advise me.
(Note: Our machines will be down(ish) from 24th Dec to Jan 5th)

Another interesting point:
I wrote a little C program print out a programs base page address and the
operating systems start of TPA pointer (at $432). When run it printed out a
high base page address eg. $23??? and $A100 for the start of the TPA which is
to be expected. But when I put the program by itself in the AUTO folder on a
floppy and booted up the machine with a power down/up it came up with $A204 and
$A100 respectively. Can anyone tell me why the OS takes this memory away?
I know I have a megabyte to play around with but I like to ponder/solve such
mysteries.

Thanks in advance and a Merry Christmas to all who know me or would like to.

Neil Forsyth (the man with the ROFDD (Read Only Floppy Disk Drive) Help!)

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"I think all right thinking people in this country are sick and tired of being
told that ordinary decent people are fed up in this country with being sick and
tired. I'm certainly not and I'm sick and tired of being told that I am!"
- Monty Python

 Neil Forsyth                           JANET:  neil@uk.ac.hw.cs
 Dept. of Computer Science              ARPA:   neil@cs.hw.ac.uk
 Heriot-Watt University                 UUCP:   ..!ukc!cs.hw.ac.uk!neil
 Edinburgh
 Scotland
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