Does the Centipede to Jamma adapter save high scores?

Archived from groups: rec.games.video.arcade.collecting (More info?)

Neverendz@aol.com wrote:
> I want to buy the one from Arcadeshop, but I'm not sure if it allows
> for voltage to save high scores.
>
> Anyone know?
>
> Thanks.
>
> , Bill

I can't remember for certain, but I do have a Jrok high score save chip
on my JAMMA-fied Centipede PCB, so that must be the reason!

Steve P

Archived from groups: rec.games.video.arcade.collecting (More info?)

C'mon guys. I have two no's, one maybe, and one yes. . . . a little
help?

Thanks.

, Bill

Archived from groups: rec.games.video.arcade.collecting (More info?)

Yeah, that's the same 15 second Google search I did. It makes sense,
but it was three years ago.

The adapter that arcadeshop sells is relatively new. So I was hoping
that they found a way around this.

I emailed Stephen Gregory about it, but I figured he won't get back to
me on the weekend. So I figured if someone on the group was using one.
.. .

On the other hand, I went to Jrok's sight and didn't see the upgrade.
But, that was late last night. . .

Thanks again.

, Bill

Archived from groups: rec.games.video.arcade.collecting (More info?)

Neverendz@aol.com wrote:
: Yeah, that's the same 15 second Google search I did. It makes sense,
: but it was three years ago.
:
: The adapter that arcadeshop sells is relatively new. So I was hoping
: that they found a way around this.

You'd need a boost DC-DC converter to up the 12V to over 17V, so that it
can be regulated down to 15, and converted to -30V on the PCB, and and
I'm sure pretty sure Gregory does't know how to design that

EAROMs aren't all that reliable anyway. It's much cleaner and cheaper to
replace it with a 2816 or other non-volatile RAM with a little plug-in board,
like JROK used to make, than to mess with a DC-DC converter.

: On the other hand, I went to Jrok's sight and didn't see the upgrade.
: But, that was late last night. . .

I don't know if it was ever on his site... A friend of mine bought one
about 5-6 years ago, when jrok was still etching boards in his basement.

--
Mark Spaeth mspaeth@mtl.mit.edu
50 Vassar St., #38.265 mspaeth@mit.edu
Cambridge, MA 02139
(617) 452-2354 http://rgvac.978.org/~mspaeth

Archived from groups: rec.games.video.arcade.collecting (More info?)

Bill Karkula <wkarkula@comcast.net> wrote:
: I bought mine from Arcadeshop and it has the on-board negative voltage
: generator for the negative supply voltage needed. I've been using it for
: over a year now to repair centipedes and it works well. Visit the
: arcadeshop site and click on the link for the photo of the adapter. The
: upper right corner has the audio amp and in the middle of the bottom of the
: board slightly to the right (to the right of the two horizontal blue caps)
: is the venerable 7660 which is a switched capacitor device to generate a
: negative voltage from a positive one.
: This should end the controversy.

If he's got a 7660 on the board, it's wired up as a voltage doubler, rather
than as a negative voltage generator, since the game board needs a high
positive voltage. Hopefully, he's using a regulator in front of it, since
the 7660 is only rated to 10.5V maximum, so using it to double the 12V wouldn't
be very friendly to the chip.

--
Mark Spaeth mspaeth@mtl.mit.edu
50 Vassar St., #38.265 mspaeth@mit.edu
Cambridge, MA 02139
(617) 452-2354 http://rgvac.978.org/~mspaeth