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Bally
16th September 2008, 11:49 PM
Hi

Maybe this will be useful for the pin owners.

If you are afraid of battery acid damage on your cpu board here is an tip for you.

Have don this on all the games that gave been in my shop and it work great.

REMOVE THE BATTERIES FIRST !

For WPC systems just remove the old ram chip at U8 and solder in an socket for the NVRAM chip.
Just an quick note:
For games that have the "midnight madness" mode you need to set the clock when you you turn on the pin,as the clock is stored in the ASIC chip and not in the NVRAM.



For Data East games just remove the old RAM chip at D5.
Cut pin 26 on the NVRAM chip and place an jumper wire from +5V to B+ on the cpu board.



For Stern and Sega White Star cpu boards remove the old RAM chip and cut pin 26 on the NVRAM chip.


Change the settings you need in the adjustments menu and you are all set for the next 10 years.


Chip used is SIMTEK STK12C86
64k NVRAM chip

AskJacob
17th September 2008, 09:23 AM
Hi

Chip used is SIMTEK STK12C86
64k NVRAM chip

Is it a STK12C68 you meant?

NVRAM is an interesting idea, however I like my clock/date functions too, so it's not for me.

A little note is that the NVRAM also has an onboard battery, safely tucked inside the chip. They too have a lifespan, but it is far longer than the AA batteries on the CPU board! (somewhere between 5-10 years I think). The battery on the chip is quite unlikely to leak...

Nice one!

Cheers
Jacob

Bally
17th September 2008, 07:27 PM
Is it a STK12C68 you meant?

NVRAM is an interesting idea, however I like my clock/date functions too, so it's not for me.

A little note is that the NVRAM also has an onboard battery, safely tucked inside the chip. They too have a lifespan, but it is far longer than the AA batteries on the CPU board! (somewhere between 5-10 years I think). The battery on the chip is quite unlikely to leak...

Nice one!

Cheers
Jacob

Ops...yeah it is the STK12C68

And if you like/need the clock-date function you need to set it every time you turn the pin on.