Pachislo Interface Board

[Compy]

Hey everyone,

I am working on a pachislo battle counter (and more) system very similar to the "PachiStat" style system, but something that does a bit more. I am looking to use a raspberry pi as they're affordable and readily available. They also have GPIO pins for interfacing with the stop board. The general idea is that statistics and such would be readily available online. Players would be able to badge in and track stats (I've got an RFID prox card reader that hooks up to USB), and eventually have a wide-area progressive bit. The reason I also want to use a raspberry pi is because products that have done these things in the past have used interfaces that are becoming lesser and lesser as technology evolves (parallel ports, serial ports, etc). So having a "drop in" system would really make things a lot easier. Plus, with the full on raspberry pi being about $40, there's no reason NOT to use it.

Before I make the feature list too grand, I want to get basic functionality working. My question right now is the interface board. I have a yamasa kiwame pachislo machine that is the "donor machine" for this project. It has the standard stop board. I am looking to tap the signals on CN4 and I'm referring to a schematic posted here. However, for these signals, it is stated that external +24V must be supplied? Is that AC or DC voltage? I have read lots and lots of posts here, but many have either not updated their threads or maybe just hadn't gotten it to work.

Does anyone have any input on this? If I missed a thread where this was uncovered, forgive me! I'm just deferring to individuals much smarter than I am about these things.

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So who am I?

I'm a software engineer (and currently a graduate student) located just outside of Atlanta, GA. I mostly write code for pinball machines, but I also make guitar effects equipment, a bunch of random arduino projects, and a computerized automatic scoring system for half scale bowling alleys. I also love visiting the casinos when I visit my family out in Oklahoma. Believe it or not, its a great family experience (Riverwind is my second home out there).

You guys are great folks, and I appreciate your help!