Stars 2020

This is the landing page for my code update of Stern Stars (1978). The new software requires a daughter card plugged into J5 (based on an Arduino Nano). The documentation for how to build the card and the rules for the new…

Continue Reading

Diagnosing a Gottlieb System 80

Recently, I got a "The Amazing Spider-Man" (Gottlieb 1980) that won't boot. I've never worked with this architecture before, so my diagnostics might seem a little haphazard, but this is my plan: Make sure the board has good power and the chips…

Continue Reading

Software – Bally/Stern OS

My goal for this software is to create an Arduino-based pinball operating system for Stern MPU-100 and Bally AS-2518-17 machines. Programming for Arduinos is very simple and the IDE isn't wonderful, but it's free. The OS will take care of all of…

Continue Reading

Switches

Reading switches is the easiest part of this process. The switches are organized into banks of 8, and each bank is energized by a different switch strobe. The lines U10A:PA0-PA4 are the strobes and the return values are read on U10B:PB0-PB7. A…

Continue Reading

Solenoids

The M6800 implementation of solenoids uses the 120Hz ISR to control the solenoids. They did this for several reasons: Time out the duration that solenoids are kept on. According to the Bally Theory of Operation document most solenoids need to be kept…

Continue Reading

Lamps

Compared to the displays, writing to the lamps is fairly easy. Well, that's not exactly true. It's fairly easy once you understand how they're using the MC14514 chip, which actually took me a little while to figure out. My first attempts weren't…

Continue Reading

Displays

The games I've worked on have five 6-digit displays. There are four player displays and one for credits/ball-in-play. These displays only show one digit at a time, but they flip so quickly between them that it looks like all six are on…

Continue Reading

PIA Chips – 6820

The 6820 PIA (Peripheral Interface Adapter) chips are how the M6800 talks to the outside world. They're used to either latch data to send to the lamps, display, or solenoids, or they're used to grab input data and hold it for the…

Continue Reading

Overview of MPU

The Stern MPU-100 is identical to the Bally AS-2518-17 board. At least I think it is. I've worked on both, I can't find any difference, and I've read that plugging the ROMs from one into the other works just fine in a…

Continue Reading

Stern MPU-100 / Bally AS-2518-17 Games

Stern MPU-100 Cosmic PrincessDraculaHot HandLectronamoMagicMemory LaneNugentPinballStarsStingrayTour De FranceTridentWild Fyre Bally AS-2518-17 301/Bulls EyeBlack JackBow and ArrowEight BallEvel KnievelFreedomMata HariNight RiderPower PlayStrikes and Spares I haven't worked with the Bally AS-2518-35, but my understanding is that it adds A14, meaning more address space…

Continue Reading

You have reached end of the world!

No more pages to load

Close Menu