Announcing new product to help resolve resets in WPC games

[mwong168]

Pinball Peers,

I want to call your attention to a daughterboard I developed to reduce or eliminate system resets related to the 5 Volt power supply in WPC era machines. I designed this new solution out of frustration with recurring resets in my Party Zone machine. In designing the daughterboard I took a holistic view of the WPC power supply designs, the loading of the supplies, the many possible weaknesses that become triggers of resets, and my knowledge of modern semiconductor products. From this analysis and through experimentation with several prototypes I determined I could safely move the power load of the MPU from the 5 volt supply to the 12 volt supply via a daughterboard that genterates and delivers a separate, stable, 5 volt supply to the MPU.

I like my daughterboard design because:
(1) It is a plug-and-play installation and the installation is completely reversible. No soldering and no wire or trace cutting is required to install the daughterboard so it can be removed from your machine as quickly as it can be installed.
(2) The watchdog circuit remains fully functional monitoring the power on the MPU board where the most sensitive chips (processor, ASIC, game roms) are located. But off-MPU hiccups no longer cascade into the MPU to trigger watchdog resets.
(3) The resultant redistribution of power loads is an improved balance across the available supplies compared to the factory design.

You can find detailed technical descriptions of my daughterboard on my KAHR.US Circuits website at http://www.kahr.us . You can buy one through my website or through eBay (note - purchases outside the United States can only use eBay).

This new solution is not intended to substitute for maintaining the power supply circuitry in WPC systems, but it does eliminate the need to fret over every hundredth of a volt.

Thanks for taking the time to take a look.

[youtube]http://www.youtube.com/watch?feature=player_detailpage&v=0gx-VYaYwAE[/youtube]

 

[Vengeance]

Re: Announcing new product to help resolve resets in WPC gam

I just saw this, I'm thinking about grabbing one, I'm still having reset issues on my CFTBL even after replacing C2, BR2 and C5.

 

[cdnpinballer]

Re: Announcing new product to help resolve resets in WPC gam

That MPU has a lot of green fuzz. Maybe this was contributing to his resets?

I hope it's not yours wong!

 

[Menace]

Re: Announcing new product to help resolve resets in WPC gam

Neat little product, and nicely done. Can't help but feel like it's a workaround, but for those with bad/low source power this would be a nice solution.

D

 

[Grauwulf]

Re: Announcing new product to help resolve resets in WPC gam

Yeah, I'm more for fixing the problem properly rather than using a band-aid.

But it is a neat idea, even if in the long run I can see it causing physical stress and cold solder joints on the MPU power connector through cantilever action.

 

[mwong168]

Re: Announcing new product to help resolve resets in WPC gam

That MPU has a lot of green fuzz. Maybe this was contributing to his resets?

I hope it's not yours wong!

Nope, I saw the creator of this post up on pinside so I was just relaying the same information here. I don't think the green fuzz was contributing to his resets otherwise his video demo would have fails. Green fuzz on the MPU usually contributes to switch matrix errors from my limited experience in dealing with board corrosion.

Just an FYI, this product is sold out. If you wanna keep track of when it will be replenished you might want to contact the seller directly via email or you can keep an eye out on this thread.

http://pinside.com/pinball/forum/topic/ ... -era-games

 

[superjackpot]

Re: Announcing new product to help resolve resets in WPC gam

I just saw this, I'm thinking about grabbing one, I'm still having reset issues on my CFTBL even after replacing C2, BR2 and C5.

PinWiki talks about the old 'BR2 C5' solution to WPC resets and goes through a pretty comprehensive list of things to check *before* you resort to this.

Have a read from section 4.8 on.

http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#Game_resets

 

[Grauwulf]

Re: Announcing new product to help resolve resets in WPC gam

I have to disagree with pinwiki, at least partially. The filter caps are getting old, over 15 years old minimum. And they really only had a service life of *maybe* 10 years, especially when you take in to consideration the heat and vibration in a pinball machine. The C5 cap absolutely needs to be changed if it hasn't already been. If you're pulling the board to inspect for cracked solder joints as they recommend, you may as well just replace it. I also do Clay's recommended trace upgrades.

 

[Shock_me]

Re: Announcing new product to help resolve resets in WPC gam

I have one of these and it works great. Until I can get more circuits wired in my gameroom I will need this device. Houses just don't seem to come pre-wired for a bunch of pinballs these days