Help on Atari 800XL required
Gerhard Pirker
Recently I got a very old Atari 800XL. I never had such a machine and so
it's something new for me.
Unfortunately I encountered the following problem:
After turning it on, there comes something like a merory-test on the screen.
It reads ROM, then there come 2 green bars.
Then it reads RAM and there come a lot of green and red squares.
I'd like to bypass this test somehow, but I do not succed.
It reads something like: 'Press reset or help to exit'.
If I press 'reset', the test starts from beginning, when I press 'help',
nothing happens...
Does anybody know what that means?
Does anybody know if there's something wrong?
Thanks in advance,
gerhard.
Ian McLaughlin
because it's detecting something wrong with your machine. The red squares
are showing you that you've got bad RAM. On some (most?) models of the
800XL, the memory is in sockets. You might want to open up your machine and
make sure that all of the chips, especailly the RAM, is seated in its
sockets properly. The RAM is the 8 small chips all in a row down the left
side of the board.
Good luck!
"Gerhard Pirker" <dig...@gmx.net> wrote in message
news:bdsf8m$10jhur$1...@ID-198914.news.dfncis.de...
Lee
You may not be able to bypass the self test if the ram fails during
power up routines that do a cursory test of ram first. Red squares
indicate bad ram on the self test so its appearent that you need to
check inside your 800XL for hot ram chips. There are 8 of them on
the left side of the mother board, bad ram often get so hot you
can't keep your finger on them so test for this carefully! Replace
all ram chips that get very hot.
At that point you should see a blue screen that says 'READY'. This
would be your Basic prompt waiting for you to type in a Basic Program.
In order to have DOS or load games you will need a disk drive and SIO
cable hooked up. Turn on the disk drive first, insert a DOS disk or
bootable game disk in the drive and then turn on the 800XL. The disk
should then boot. If you want to bypass Basic you should hold down the
OPTION key while powering up the 800XL. Look for a message with the
title 'Welcome to Comp_Sys_Atari_8bit' for this group's FAQ - read, read
and read some more in order to come up to speed on your 800XL. Best of
luck...
Roy G Biv
->You;ve got bad RAM. The screne coming up is the self test. It's
->coming up because it's detecting something wrong with your machine.
It's not necessarily a RAM problem or something wrong with the
computer's innards. It's also possible that it's running the self-
test because the IO (daisy chain) connection is bad. That's happen-
ed to me many times over the years. I've found that on XLs and
especially XEs, the IO connections are extremely fragile.
Nudging or jiggling the cable a little bit can make a big differ-
ence. It can also blow out the whole computer! Futzing with the
cable to make sure the connection is solid is something that should
be done ONLY with the entire computer system turned OFF! It's best
to cover over the daisy-chain cable where it plugs into the computer
to try to make sure the cable connection is never disturbed!
I've also found that if the daisy-chain cables connected to
other hardware items are disturbed, that can also cause the computer
to go into self-test mode.
Another question is whether the original poster has any other
hardware hooked up to his computer? If there's no disk drive with
a DOS disk in it, isn't an XL/XE going to automatically go into
self-test? After all, self-test replaced the "memo pad" mode that
was on the original 400/800s.
--
>>>----------------------------------------------<<<
>>> david moeser -- erasmus39 on yahoo <<<
>>> Censornati, Ohio - USA <<<
>>>----------------------------------------------<<<
* Question: 8 bits + 8 bits = ? Answer: two 8 bits! *
(Headers munged to foil spammers; real info in taglines)
Shawn Jefferson
> Another question is whether the original poster has any other
>hardware hooked up to his computer? If there's no disk drive with
>a DOS disk in it, isn't an XL/XE going to automatically go into
>self-test? After all, self-test replaced the "memo pad" mode that
>was on the original 400/800s.
Without holding down the option key on the XL/XE (excluding the 1200XL) you
get the BASIC, READY prompt. If your computer goes into self test mode
when you turn it on, without holding option down, regardless of peripherals
installed, I'd say you have something wrong with the RAM.
You can carefully pull and reseat the chips and try the temperature test
given earlier to try and find the bad one. I don't know how the little
blocks in the self test correspond to the physical chips. Does any one
know?
---
Shawn Jefferson
(fix reply to for email)
Lee
At one time I had it figured out but there is a basic flaw in straight
thru thinking that makes it all not apply. First there is a hole in
ram that is not tested, 3000-3800 or somesuch that holds the results
and then ram under rom is not tested, nor 5000-5800 as that is ROM
while the self-test is on. So each block doesn't map out to a linear
feild as it is displayed as such to start with. Then there is the fact
that each ram chip is responsible for only one bit of all addresses
possible which in my mind at least ruins any chance for 'reading' the
screen results and drawing any conclusion as to which chip to replace.
Much better and far more accurate to replace the ones that burn your
finger.
The default behavior for a standard 800XL is to boot to Basic if there
is no disk drive attached. However problems with PIA can sure cause
self test too - but the test shows bad ram so start there I say. I'm
thinking that if you boot with Option down and you don't have a disk
drive attached - then you get self test on a standard 800XL.
Gerhard Pirker
> Recently I got a very old Atari 800XL.
> Unfortunately I encountered the following problem:
> After turning it on, there comes something like a merory-test on the screen.
> Then it reads RAM and there come a lot of green and red squares.
Thank you guys for all your information!
Last weekend I found some time to try out your suggestions.
I opened the machine and checked if the RAMs get hot after turning it on.
But (un)fortunately the RAMs remain completely cold.
Instead, one of the two ICs called '8327' gets very hot very quickly after
turning on, the other '8327' remains cold.
The other big ICs get warm after some minutes, but just a little...
What job does the left '8327' and can this be the reason for the memory-test
after turning on the machine?
Do you think it makes sense to get some other 8327 for replacement?
Btw: I did not connect the floppy drive, so there cannot come any influence
from that.
Best regards,
gerhard.
Paul Alhart
>
> I opened the machine and checked if the RAMs get hot after turning it on.
> But (un)fortunately the RAMs remain completely cold.
> Instead, one of the two ICs called '8327' gets very hot very quickly after
> turning on, the other '8327' remains cold.
> The other big ICs get warm after some minutes, but just a little...
I believe 8237 is the date code and not the part number. Can you supply
another number from the chip like ( CO12498 or SN74138) or the IC location
on the board like(U22 or U6)?? If so, I can be of more help. Paul
Bob Woolley
multiplex the memory addresses and could very well be your problem. Of
course, the 8327 is a date code.... these could be two completely different
chips! Look for something like 74LSxxx or some such.
Bob
"Gerhard Pirker" <dig...@gmx.net> wrote in message
news:bfedd3$dlgkj$1...@ID-198914.news.uni-berlin.de...
Gerhard Pirker
> I believe 8237 is the date code and not the part number. Can you supply
> another number from the chip like ( CO12498 or SN74138) or the IC location
> on the board like(U22 or U6)?? If so, I can be of more help. Paul
You are absolutely correct, this is the date code. ;-)
Sorry bout that fault...
The number on the chip reads C014806-12 and 11151-12
and on the board there is written U8.
regards,
gerhard.
Russ Gilbert
the U8 CO14806 is the 6502C CPU chip, 2nd
LSI from right at the 'bottom' 4 LSIs.
I don't know if it should get hot.
The 11151, I dunno.
Sometimes, you can fix a A8 by swapping out
known good chips, ie. you need a 2nd working
800XL and for the major chips to be socketed.
I also muck with a logic probe, comparing the
bad computer with the good board.
The 4 LSI chips at the bottom of the board are
GTIA, U17, (left), U7 Antic, U8 6502C, U23 PIA.