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Path: utzoo!utcsri!ubc-vision!alberta!calgary!ingoldsby
From: ingoldsby@calgary.UUCP (Terry Ingoldsby)
Newsgroups: net.micro.6809
Subject: Newdisk bugs?
Message-ID: <94@vaxb.calgary.UUCP>
Date: Tue, 22-Apr-86 11:41:40 EST
Article-I.D.: vaxb.94
Posted: Tue Apr 22 11:41:40 1986
Date-Received: Tue, 22-Apr-86 16:04:58 EST
Organization: U. of Calgary, Calgary, Ab.
Lines: 29
Keywords: Device Driver


    I recently attempted to install the `Newdisk' device driver that
was posted to the net by Dave Lewis.  I have had some problems and
was wondering if anyone else has experienced similar difficulties.

    Assembling Newdisk and installing it using OS9Gen went fine.  The
driver works just fine until an error condition occurs.  It doesn't seem
to matter what the error is; the easiest error to fake is attempting to
write to a write protected disk.  Anyway, when an error occurs the driver
takes up transcendental meditation and I have to reboot the system.  My
attempts to debug it have convinced me that when an error occurs, execution
does indeed vector to the error handler contained in the driver.  What
happens next is not at all clear but I almost think that another NMI is
occurring a `short' time later.

    Debugging this routine is not a trivial task due to its interrupt
driven nature, and I tip my hat to Dave Lewis for writing the beast.
Its really very tight code and I'd like to get it working.  I should
mention that I have the old gray Coco and the old disk controller.  If
anyone else has had these problems I'd appreciate hearing from them.  If
no one else has had these problems then perhaps I've got a bad copy of
the driver and someone would be kind enough to mail me another copy.

    One final question: Is it permissable to do system calls within
a device driver?

				Terry Ingoldsby

Disclaimer:  No one around here even cares what I say.