TECH: Dig Dug problem - "RAM OL"
The Jaded Gamer
The game won't go into self-test, and only says "RAM OL" twice (upside
down in the lower right hand corner) along with some other garbage on
the screen that flashes on and off (www.yorkiedog.com/misc/digdug.jpg
& www.yorkiedog.com/misc/digdug2.jpg). The manual states that the
"RAM OL" message indicates a bad RAM chip at location 9M on the PCB.
However, I can't find the "9M" location to save my life. I can see 1M
through 8M (as well as 10M), but not 9M.
The power supply has recently been changed and is in good condition.
Also, the
game makes a high pitched whine while it is running. Anyone know what
the problem might be?
Thanks in advance for any help!
Brent Cobb
Just a thought though, maybe the 9M chip is missing, that's why you can't
see it?
Like I said I have no idea.
Good luck.
Mark C. Spaeth
: I'm having some trouble with a Dig Dug that I'm trying to get going.
: The game won't go into self-test, and only says "RAM OL" twice (upside
: down in the lower right hand corner) along with some other garbage on
: the screen that flashes on and off (www.yorkiedog.com/misc/digdug.jpg
: & www.yorkiedog.com/misc/digdug2.jpg). The manual states that the
: "RAM OL" message indicates a bad RAM chip at location 9M on the PCB.
: However, I can't find the "9M" location to save my life. I can see 1M
: through 8M (as well as 10M), but not 9M.
There are 2 different PCB layouts for atari digdug... spies has PDFs with
the self-test results and corresponding chip locations for both boards.
...sounds like you're looking at the manual for the wrong board type.
: The power supply has recently been changed and is in good condition.
: Also, the
: game makes a high pitched whine while it is running. Anyone know what
: the problem might be?
Some digdugs do this during self test, until the sound circuitry is reset.
--
Mark Spaeth msp...@mtl.mit.edu
50 Vassar St., #38.265 msp...@mit.edu
Cambridge, MA 02139
(617) 452-2354 http://rgvac.978.org/~mspaeth
Grimly
Check your voltages, as this could be causing the other problem.
The whine could, however, just be a noisy flyback in the monitor.
Sometimes voltages can read OK but the waveform from the power supply
is crap, which can also cause problems. Try a different power supply
if you have one.
You could also verify the supply by trying a different board set in
the game.
The component location numbers and letters on the board are usually
used to identify component location on the board. IC 9M should be
right in between 8M and 10M. They usually use letters along one edge
of the board and numbers along the other to locate the ic's.
Remove the obvious to e-mail.
The Jaded Gamer
> the self-test results and corresponding chip locations for both boards.
> ...sounds like you're looking at the manual for the wrong board type.
Yep. The manual that I was referring to was for PCB type A. Luckily,
I followed a link from Spies and found the manual for PCB type B at
www.stormaster.com/RGVAC-Manuals/PDF-Arcade/. Instead of looking at
chip 9M as the source of the "RAM OL" message (which doesn't exist on
my PCB), I need to look at chip 4K.
I'll have to check it out when I get home from work and see what's up
with it.
By the way, if I need to replace that particular chip where might I
find one? Bob Roberts?
Thanks for the help guys!
Mark Wilson
sounds.
on my board the RAM is located in the K-4 spot, it is a 6116P-3.
my book shows the OL in the 9-M spot too, I spent a while looking for
it. I then did a Google search to find out mine has a different board
too.
let me know if you get your's fixed, I still need to go find new RAM
chips for mine next week.
Mark
Mark Wilson
Grimly
Try