[comp.sys.amiga.tech] Weird A1000 problem

cmcmanis%pepper@Sun.COM (Chuck McManis) (04/18/89)

In article <80@estinc.UUCP> fnf@estinc.UUCP (Fred Fish) writes:
>I am posting this note for my brother, who recently acquired another
>Amiga 1000.  This one has a wierd problem.  I'll pass on any replies
>to him...
>
>The Problem!
>
>	The problem only seems to manifest itself on the 
>	Workbench screen.  You can only move icons around within
>	a rectangular area between the title bar and 1.75 inches
>	below it.....
	[And yet every thing else drags properly ...]

>	Once the display locks up, if you pop out the disk and pop it back
>	in, it becomes "unlocked", that is to say, it operates as "normally"
>	as it did before it locked-up. 
	
	This is what worries me. If you were a virus, playing pranks on the
	user like this, when would you go do something else? When the disk
	was replaced of course! To see if you could infect it as well. Since
	this is "another" A1000 my suggestion would be to try it's workbench
	disk on the first one. And see if the "old" A1000 starts exhibiting
	the same symptoms. 

	The other more mundane possibility is that the EPROM in the kickstart
	eliminator dropped some bits. (Which it would do if it was exposed to
	UV for any length of time). Try a new set of Kickstart EPROMs if the
	virus idea doesn't pan out.



--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.
"A most excellent barbarian ... Genghis Kahn!"

manes@cs.odu.edu (Mark Manes) (04/18/89)

In article <80@estinc.UUCP> fnf@estinc.UUCP (Fred Fish) writes:
>I am posting this note for my brother, who recently acquired another
>Amiga 1000.  This one has a wierd problem.  I'll pass on any replies
>to him...
>
What, could this be true... Do I get to help someone finally!?
 
Yes, I have seen something similiar in my past with a Amiga 1000.  
Have your friendly Amiga dealer (or yourself) replace the 8520 chips.
This cured the 1000's problem.

The problem you described is not exactly what I encountered, but very
very close.
 
-mark=


>==========================================================================
># Fred Fish, 1835 E. Belmont Drive, Tempe, AZ 85284,  USA
># 1-602-491-0048           asuvax!{nud,mcdphx}!estinc!fnf

---------------------------------------------------------------------------
Mark D. Manes                                          "In Amiga We Trust"  
Programmer of Fortune, have compiler will travel

"Only Amiga makes it Possible, but with 1 meg its hell!"
===========================================================================

pmf@mimsy.UUCP (Paul M. Franceus) (04/22/89)

Your wierd problem is most likely caused by a bad 8520 chip.  I had problems
once very similar to yours and it was fixed by replacing one of the 8520's.

These chips are Commodore's custom serial, timer, VIA chips.  They are locateded
in the back right corner of the motherboard near where the floppy cable 
connects.  You can get them from any C= dealer.

Hope this helps.
   Paul
StarLight Technologies.

fnf@estinc.UUCP (Fred Fish) (04/26/89)

In article <8522@xanth.cs.odu.edu> manes@cs.odu.edu (Mark Manes) writes:
>Yes, I have seen something similiar in my past with a Amiga 1000.  
>Have your friendly Amiga dealer (or yourself) replace the 8520 chips.
>This cured the 1000's problem.

Thanks to all who gave similar advice.  It does appear that this was
the problem.  My brother replaced the 8520 chips and all is well again!

-Fred
-- 
# Fred Fish, 1835 E. Belmont Drive, Tempe, AZ 85284,  USA
# 1-602-491-0048           asuvax!{nud,mcdphx}!estinc!fnf

hr@rigel.astro.uiuc.edu (04/28/89)

RE:

  ">Have your friendly Amiga dealer (or yourself) replace the 8520 chips."

Is there a good place I can order 8520s? I just blew up my 1000 again this
weekend and can't even boot now. (Something to do with turning on the
printer or using the switchbox). The last time I replaced the chips, my
dealer sold me a pair from an existing machine, and made me give him my
old ones. I'm hesitant to try again.

If I were to put, say, 50 ohms resistors in the signal lines,
would this likely be useful protection?


Harold Ravlin