[comp.sys.mac.system] MacIIci hangs in disk reads by Pyro & Sum Shield

flowers@lanai.cs.ucla.edu (Margot Flowers) (08/16/90)

We have a MacIIci with Apple (Quantum) 80mb hard disk.  A couple of
days ago it started hanging during both Pyro 1.0 and SUM Shield volume
protection (which was waking up every 60 minutes), with the disk
access light on.  At this point the programmers switch will not
interrupt and we have to reboot.  There has been no new software
installed on this machine in a while to have changed the environment.
Does anyone have any experience with this or any guesses as to cause?

The hard disk has always seemed flakey since it had the random hard
 disk noise that others described recently, but in the last few months
that noise has been getting very hard to eliminate when it does occur.
The usual techniques of menu access or program launching don't
ususally work anymore.  I'm curious as to what interactions between
software and hardware are involved, since this hanging occurs only
during the only two auto-waking programs on the system.  
 
By the way, many people posted "me too" messages about the MacIIci
disk noise, but if there were any explanations, I missed them.  What
is the cause of this periodic noise?

thanks for all info,
Margot Flowers 
Flowers@CS.UCLA.EDU 
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