Tech: Do WPC machines lose track of the day if left unpowered for more than a month?

beaver

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Mar 12, 2008, 9:55:22 PM3/12/08

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I have been working on my WPC/ASIC replacement project, and working on
the date/time/hour portion. From looking at the interface, it seems
to me that the real-time clock does maintain time when powered off,
but it loses track of the day if you leave the CPU board unpowered for
more than one month. At that point, the day counter wraps around, and
you are now off by one month on the display.

Can anyone corroborate this?

WPC/ASIC project info page:
http://www.edcheung.com/album/album07/Pinball/wpc_sound.htm

Edward Cheung CARGPB26

GPE

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Mar 12, 2008, 10:03:04 PM3/12/08

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"beaver" <e...@edcheung.com> wrote in message
news:b14f093e-6127-46c3...@a1g2000hsb.googlegroups.com...

Hi Ed,

I can't answer the question... but am curious on this project. How have you
managed to simulate this ASIC? I know you can do alot with the Xilinx
FPGA's - I use them often. But how did you figure out what was in the
Williams ASIC to begin with? Did you find something that defined it at the
register/memory map level? Or trial and error on each of the signal lines?
Reverse engineering? A bit of all the above?

What you have does sound like an excellent candidate for WPC replacement in
the future.

Keep up the interesting website...
-- Ed K

beaver

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Mar 12, 2008, 10:12:07 PM3/12/08

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Finding out what is inside the ASIC has been done from:
1) The .h file from PinMAME, WPC.H. This has been a great starting
point. It has the memory map.
2) From friends such as Brent and Martin.
3) From my own investigation with a Logic Analyzer hooked up to my
reference WPC board.

The individuals who have contributed have all been attributed on my
page, and it has been like solving a puzzle. It has been fun and
interesting. I sometimes cannot believe I have the guts of a pinball
machine running on my Xilinx board, and using my VGA monitor on my
desk as the DMD.

Edward Cheung CARGPB26

Joseph A. 'Tony' Dziedzic

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Mar 12, 2008, 10:13:54 PM3/12/08

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Yes, Ed, that is my observation based on my games.

Joseph "Tony" Dziedzic

In article <b14f093e-6127-46c3...@a1g2000hsb.googlegroups.com>,

beaver

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Mar 13, 2008, 7:06:33 AM3/13/08

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Thanks Tony.

Edward Cheung CARGPB26

On Mar 12, 10:13 pm, t...@dziedzic.us (Joseph A. 'Tony' Dziedzic)
wrote:

> Yes, Ed, that is my observation based on my games.
>
> Joseph "Tony" Dziedzic
>

> In article <b14f093e-6127-46c3-b97a-bc11524e6...@a1g2000hsb.googlegroups.com>,

kirb

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Mar 13, 2008, 9:08:30 AM3/13/08

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I wondered why my clock wasn't that far off, but my day and year would
get all messed up....

I have a few games that sit idle longer than they should and the dates/
years get screwed up on ALL of them.

Kirb

beaver

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Mar 13, 2008, 10:19:10 AM3/13/08

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Aha. That is exactly what would happen if I my understanding of the
way the ASIC works is correct. The time will be fine, but the day and
year will not. It takes 31 days from the previous power up before
this occurs. Thanks.

Edward Cheung CARGPB26

kirb

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Mar 13, 2008, 10:29:15 AM3/13/08

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> > Kirb- Hide quoted text -
>
> - Show quoted text -

Thank you for letting me know that I need to power up my games more.

jtk