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Ramtron NVRAM 8k 2064 6264 SRAM replacement and 2k 6116 SRAM replacement

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Bob D.

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Mar 12, 2012, 5:02:07 PM3/12/12
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I was going to hold off and wait until it was closer to the Allentown
Pinfest time frame but due to recent circumstances I will add to the
NVRAM fire sale and also put my version up for sale.

The RanD Electronics NVRAM adapter will replace the 28 pin 6264/2064
8k SRAM used in Williams system 11 and WPC and can also be configured
to replace the 6116 2k SRAM used in the Williams system 11 boards.
Yup This adapter will replace either the 2k SRAM or the 4k SRAM
version. Just a matter of a few blobs of solder on the PCB to select
between the two versions. If the 24 pin chip is being replaced, a few
unconnected pins will overhang the socket.

If you current SRAM is socketed then replacing you battery backed
SRAM is a piece of cake. Just pop out your old SRAM, remove your
batteries and, replace old SRAM with new NVRAM. Done.

If your old ram is socketed then you would have to desolder your old
SRAM from the board. Then install a machine pin socket, which will be
provided. Now remove your old batteries and pop in your new NVRAM.

$16ea for 8k NVRAM adapter and 28 pin machine pin socket.

Pictures can be seen here:
http://www.flickr.com/photos/33796700@N06/sets/72157629207061028/

But wait there’s more. If you plan to attend the Allentown Pinfest
show in May then bring your non acid damaged board to the show and I
will remove your old socketed SRAM and replace it with a machine pin
socket for the low price of $5ea. At this time I do not know If I
will be in the indoor flea market area or working out of the back of
my van. Please email me and let me know in advance if you plan to
purchase this service.

NOTE: This should also work in Data East boards but I can’t fully
guarantee that it will. The RAMTRON NVRAM specs note that the address
being read/write to is latched in on the CE’ transition. The Data
East boards have the CE’ tied to gnd. I have replaced several SRAMs
in Data East boards and the NVRAM seems to work just fine.

Disclaimer:

I do not anticipate problems but due to the cheap rework price and
lack of testing equipment I will bring along To the Allenton Pinfest I
can not be held responsible for the board "not working" after I
install the socket as I will have no way to test the board “before/
after” adding the socket. I will be using safe desoldering techniques
and have been repairing electronic equipment for more than 20 years
and have repaired hundreds of misc pinball/arcade boards.

Bob D.

unread,
Mar 12, 2012, 4:55:39 PM3/12/12
to
I was going to hold off and wait until it was closer to the Allentown
Pinfest time frame but due to recent circumstances I will add to the
NVRAM fire sale and also put my version up for sale.

The RanD Electronics NVRAM adapter will replace the 28 pin 6264/2064
8k SRAM used in Williams system 11 and WPC and can also be configured
to replace the 6116 2k SRAM used in the Williams system 11 boards.
Yup This adapter will replace either the 2k SRAM or the 4k SRAM
version. Just a matter of a few blobs of solder on the PCB to select
between the two versions. If the 24 pin chip is being replaced, a few
unconnected pins will overhang the socket.

If you current SRAM is socketed then replacing you battery backed
SRAM is a piece of cake. Just pop out your old SRAM, remove your
batteries and, replace old SRAM with new NVRAM. Done.

If your old ram is socketed then you would have to desolder your old
SRAM from the board. Then install a machine pin socket, which will be
provided. Now remove your old batteries and pop in your new NVRAM.

$16ea for 8k NVRAM adapter and 28 pin machine pin socket.

Pictures can me seen here:

AceBH

unread,
Mar 12, 2012, 5:26:02 PM3/12/12
to
On 3/12/2012 5:02 PM, Bob D. wrote:
> I was going to hold off and wait until it was closer to the Allentown
> Pinfest time frame but due to recent circumstances I will add to the
> NVRAM fire sale and also put my version up for sale.
>

The more, the merrier.. cheap NVRAM for all in 2012! lol. That's a hard
price to touch if it includes shipping, so hoping not? =) I made 10 of
these and in somewhat of an assembly-line approach after about 6
one-offs for my own machines and it still took me 20-30 min each & then
time to test them. The SOIC soldering of course takes the most time..
hunched over, tense detailed work. Need good eyesight which I'm still
somewhat gifted with at this point. Machine pin sockets are a walk in
the park.

Very cool that you are providing a service to install a socket for $5 at
the pinball show too. That helps out anyone putting this in a Williams
Board. So far all my Data East machines have worked just fine with the
NVRAM just fyi.

A while back I had actually thought about a single board that could be
jumpered for 6116, 5101 or 6264.. or some piggyback setup of boards.
Probably easier to do something like that for RAM that is closer in
pin-out though like the 6116 & 6264 though, otherwise way too many
traces and jumpers running all about.

-Wayne
(yes I share the same name as that Australian guy -- all Waynes are not
evil :)

--
http://www.techdose.com
http://www.tutorialgrub.com

Bob D.

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Mar 17, 2012, 8:16:58 AM3/17/12
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On 3/12/2012 5:02 PM, Bob D. wrote:
Just a bump

Anthony Bacus

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Aug 12, 2012, 3:03:15 PM8/12/12
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If you current SRAM is socketed then replacing you battery backed
SRAM is a piece of cake. Just pop out your old SRAM, remove your
batteries and, replace old SRAM with new NVRAM. Done.

If your old ram is socketed then you would have to desolder your old
SRAM from the board. Then install a machine pin socket, which will be
provided. Now remove your old batteries and pop in your new NVRAM.

Do you mean "If ypur old ROM is NOT socketed then you would have to
desolder your old SRAM"? I am confused, because I want to replace a
6116. It is not socketed, and there is no battery. This whole MPU/Chip
board thing is new to me, and I confuse easily. I just want to be sure I
do it right. Do you know if the U23 and the U25 are supposed to be
6116's? Because my Swords Of Fury MPU has a 5516AP in it's U25 slot.


--
Anthony Bacus
This USENET post sent from http://rgparchive.com

seymour.shabow

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Aug 12, 2012, 4:08:24 PM8/12/12
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System 11 boards can take various types of ram. The software all seems
to top out at only using $000-$7ff though, so larger rams were supported
in hardware but the software doesn't need it (at least up through
whirlwind/radical, around there)

Just changing the ram won't work though as nvram unlocks at varying
voltages close to 5 volts - you have to jumper out a diode that's in
place on system 11 boards to allow it to work correctly. The diode is a
1n5817 that's there to prevent batteries from powering the board. WMS
clearly had a problem with normal ram in there since earlier boards
(system 7/9) use 1n4148's (which have a larger voltage drop) vs. the
5817 (which has a very small voltage drop around .2 volts)

But yes, just popping in the other ram, if socketed, would work.
Jumpers might have to be set, the system 11 schematics show all the
jumpers and their uses (as did clay's old system 11 guides IIRC)

Hammer5550

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Nov 8, 2012, 2:10:55 AM11/8/12
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Are you still selling these? I am interested in buying some if they are still available
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