I took a brief look at the schematic and it actually looks like a really good case for modernization. Lots of 74 series style logic that could be wrapped up in CPLD or FPGA. The major down sides I see are the limited market and the oddball super rare CPU that's used. I couldn't easily find a 2650A CPU core for FPGA. I'm guessing there isn't one because it's pretty rare and would be in low demand. If a VHDL CPU core were available it would make the project a LOT easier.

Interesting idea. Not something I'd personally pursue.

I'll do it. $10K/board including working prototype and gerbers based on original designs (no addition of CPLD, etc...). That may sound like a high number but honestly I would still be somewhat hesitant to not just sell the finished boards myself. You're never going to make that kind of money from Zaccaria, but you can be sure that a company like Alltek has made multiples of that selling the Bally stuff. I have finished designs in the can for Bally/Stern and Williams 3-7. What I don't have is spare time in my life to actually prototype them and probably won't any time soon.

Or just do it yourself.

That's what I would really recommend. If you're looking to work from gerbers in the first place, it's not tough to take the schematic, dump it into Eagle and create a board. The tough part is in the component placement and routing, but people seem to be happy with boards based on the layout of the originals so it's not tough to get it to that stage. I would be happy to give you advice for free on any of that stuff. I'm not the best circuit designer ever, but I've been designing PCBs for pinball for over ten years and I've done lots of boards for pinball in that time and come a very long way in terms of component layout and routing. I love designing the boards. I just don't love assembling and shipping them so most never see the light of day. I don't really see someone coming up with well designed gerbers for pinball MPUs that they're going to sell "cheap" unless it's not their original work because there is actually a lot of profit to be made in some cases (not Zaccaria, IMO), but who knows. Stranger things have happened in pinball.

Personally, I would not consider hand assembling them using through-hole components like the originals. That's going to take FOREVER and eat up all potential profit.

http://www.cadsoftusa.com/eagle-pcb-design-software/about-eagle/

I've always liked the way Bally designed their system too. The way they multiplexed the PIA outputs of U10 is really an efficient use of the PIA.

Cool stuff! It's a good idea to add LED support to the lamp driver if you're planning to sell them. Here's a proof of concept layout I did of the Bally lamp driver board as an example of a different approach to that board. I used SMD SCRs but DIP would fit in the same space and basically route the same:

Aux_Lamp_Driver_Example.png

For the 5101-6264 adapter, the 5101 package will fit under the 6264 if you use the smaller pads on the 5101. That would make the board quite a bit smaller, relatively. I've given examples on the forum for combining the enables of the 5101 to add Gottlieb System 80 support and isolating the inputs and outputs of the 5101 with a 74LS244 to add Gottlieb System 1 support. It's worth considering adding that stuff to expand the potential market.

I've also been considering adding a jumper to my 5101 and 6116 NVRAM adapters for two banks of RAM. I think some people would like that. In theory, you could then run a switch to the coin door to switch between two sets of audits, high scores, etc... or just leave the jumper and switch it that way. That's something else to consider adding.

An MPU is a different universe than these small boards in terms of routing and prototyping, but it's not rocket science. You can definitely get there with enough time and effort.

Good ideas. The basic design I posted has the load resistors for LED compatibility as SIP resistor networks. I was also planning to add indicator LEDs to the SCR outputs. I've been designing a lot of these smaller boards lately using as much SMD as possible because I would like to eventually get a pick and place machine. SMD LEDs would be a lot cheaper and you can place them right by the SCR, but the DIP bar graph LEDs would also work.

The best advice I can give you is to learn how to make your own packages in whatever design software you're using right away. It's one of the most important things, IMO. When I do stuff for pinball now I end up just making most of the parts myself because it gives me the most flexibility.

Here's an eagle library with a 5101 using the smaller holes, as an example.

http://pinforge.com/Eagle_Example/5101_Example.lbr

I really like Eagle, personally, but it's the only one I've ever used so I have no frame of reference. It works well for me so I stick with it.

I assumed you were planning to stuff a 6264 NVRAM adapter in the 6264->5101 board you posted which made me wonder why you didn't just do a NVRAM-> 5101 board, though there's probably a small market for people who want to use a 6264 chip in a 5101 socket with batteries.

I wasn't easily able to find them. I'll repost later when I have more time to dig up the schematic examples.