[comp.sys.atari.st] Broken ST

mkentley@wpi.wpi.edu (Michael J Kentley) (02/15/89)

	Lately one of my ST's has been acting up and I wonder if anyone out
there has had the same problem that I am having with it.
	First, its a 520 upgraded to a meg. 
	The problem is, that after I've been using it for an hour or so the 
beast just seems to keel over.  I will get either 2 or 4 bombs and the system
freezes. 
	When I reboot, just before the desktop should come up, 2 or 4 bombs
flash on the screen, the screen boes black, then it it tries to reboot.
This happens over and over until I shut the machine off. 
	If I leave it alone for a few hours, and then turn it back on, it acts
as if nothing was wrong, for about an hour, then the whole thing starts over 
again. 

	Does anyone have a clue as to what might be causing this??? My BBS is
running on only .5 meg till I get this fixed. 

	Thanks for the help.

mkentley@ame ji.wpi.edu (Michael J Kentley) (02/15/89)

	Lately one of my ST's has been acting up and I wonder if anyone out
there has had the same problem that I am havtng with it.
	First, its a 520 upgraded to a meg. 
	The problem is, that after I've been using it for Bn hour or so the 
beast just seems to keel over.  I will get either 2 or 4 bombs and the system
freezes. 
	When I reboot, just before the desktop should come up, 2 or 4 bombs
flash onisius fscreen, the screen boes black, then it it tries to reboot.
This happens over and over until I shutwate machine off. 
	If I leave it alone for a few hours, and chen turn it back on, it acts
as if nothing was wrong, for Bbout an hour, then the whole thing starts over 
again. 

	Does anyone have a clue as to what might be causing this??? My BBS is
running on only .5 meg till I get this fixed. 

	Thanks for th

IA0@PSUVM.BITNET (02/16/89)

I also have a broken 520 STFm, which I was trying to upgrade to 2.5Mb.  The
upgrade unit did not fit well in the case, so I was trying to adjust the
template which pushes into the MMU chip, then powering up and counting memory.
At one point, the system failed to boot.  So I removed the new ram.  It still
won't boot.  The upgrade consisted of a video piggy back card and the MMU
template.  The current symptoms:  no video, no disk-access light, but the
disk head does move a bit when powered up, and I can hear the video whine.
I suspect problems with either the MMU or video chips, since they are the
ones that get moved/plugged-into.  Any ideas?  I'm dead in the water at the
moment.

David Huenemoerder PennState Dept. of Astronomy
internet: dph@astro.psu.edu (128.118.30.150)
bitnet: ia0@psuvm

hedger@inmet (02/17/89)

I'd check for a weak solder joint or bad connection especially around
the upgrade. If it's the plug in type, I'd open up the ST and give the
plug in chips a good push to make sure they are tight. 


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| Keith Hedger :  {...!}uunet!inmet!hedger   hedger@inmet.inmet.com |
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mc2818@uxf.cso.uiuc.edu (02/20/89)

I believe the problem is with the video chip pins.  I tried upgrading
my ST to one meg, and when it didn't work, I removed everything, put
it all back and it didn't work!  Turns out that the pins on the video 
chip weren't making good contact.  So, bend the pins out a bit and
reinsert it.  Hope it helps.         -Mike

michaels@tekigm2.MEN.TEK.COM (Michael Schaeffer) (02/24/89)

In article <71682IA0@PSUVM> IA0@PSUVM.BITNET writes:
>I also have a broken 520 STFm, which I was trying to upgrade to 2.5Mb.  The
Same story here: 520 ST, EZRAM-II upgrade, bombed out of a program
repeatedly one evening this week, will not boot properly since (say twenty
cycles through the on-off and/or reset caused it to lighten the screen,
read drive A, bring-up the desktop with a frozen mouse, die with two black
bombs, and four striped bombs; next reset, a constant row of black bombs.

To the net - can someone post a listing of bomb pattern to error code
conversions please  ...  monthly!

To Atari - could you please never introduce a computer manual on the
market again without including an error code listing!
                                    |\
 I am Michael Schaeffer     |\  |\  |   |\     
 I talk 206.253.5395        |   |  <>   |   > > > > 11001011 00101101
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kirkenda@psu-cs.UUCP (Steve Kirkendall) (02/25/89)

In article <71682IA0@PSUVM> IA0@PSUVM.BITNET writes:
>I also have a broken 520 STFm, which I was trying to upgrade to 2.5Mb.  The
>upgrade unit did not fit well in the case, so I was trying to adjust the
>template which pushes into the MMU chip, then powering up and counting memory.
>At one point, the system failed to boot.  So I removed the new ram.  It still
>won't boot.

This is just a guess, but...

The "template" which you insert between the MMU chip and its socket probably
bent some of the socket's connectors, so that they no longer make a reliable
connection to the chip.  If this really is your problem, you can fix it by
taking a piece of wire, bending it to make a hook, and using the hook to
pull the connectors back into the proper shape.

(I had a similar problem once, and that fixed it.)

-- 
"If I seem insensitive to what you're going through,
	keep in mind that's the way I am." -- Mr. Spock