American Girl Pinball Teardown 2: Circuitry analysis

Dismantling "The Flip Side", a 1:5 scale pinball machine created by American Girl (the doll company). This is the 2nd video in a series where I disassemble and reverse engineer this cool little machine. In this video we examine the backbox and playfield circuitry. We find out how the machine works by mapping the circuits for power, lighting, switches, optical sensors, motor control, audio output, and memory. We also discover that the original software doesn't make full use of the machine's lighting capabilities.
00:00 : Objective
00:29 : Tracing a circuit (optical switches)
18:33 : Summary of each circuit on both boards
39:34 : Functions of the main microcontroller; lighting and switching capabilities
See the rest of the teardown series and my review of the machine before I tore it apart:
• American Girl Pinball

[@TheFiftyQuid]

Nicely done. Oh and I appreciate the time you took to get the proper font for your title. Very nice touch. It took me about 20 minutes to realize it was your cat meowing after telling mine to be quiet multiple times. LOL.

[@kyle5574]

Fifty Thanks! Yeah, I either close the door and listen to her meow or open the door and have her walk all over the circuit board.

[@klacustoms]

Was wondering, is there any way of changing out the Opto sensors and putting in microswitches instead? So when a pinball rolls over the microswitch, have it become a closed circuit? Wondering if this could be possible and how it could be done.

[@kyle5574]

It'd be pretty cool to convert this machine into something with a more traditional playfield with mechanisms mounted underneath like that. As-is though, I think you'd run into some challenges. There's not much room between the playfield and the PCB to mount switches. You'd have to find some pretty small switches too since the ball is so small/light. If I was going to tackle something like that, I think I'd try to replace the flippers instead. It'd be pretty sweet to have little electronic solenoid-driven flippers instead of manual ones!

[@klacustoms]

@@kyle5574 Actually I was thinking of using this on a fullsized pinball machine with missing backboard and CPU. Cut a slot in the playfield apron to house the score display. Mount this underneath playfield on the one side of the machine which would be plenty of clearance and no interference to any of the mechanical components by the flipper mechanism underneath. So as you're playing the game, all you have to do is look down by your left hand to see your score, instead of seeing it in the backbox. For the scoring itself, hardwire the scoring to the schematic of the wires of the actual pinball machine so you're still using and utilizing all the wiring from the targets of the game but to American Girl scoring instead. For all the solenoids, have them wired up to different power supply units 24vdc for flippers for example that run independently from American Girl. Just using American Girl for scoring only but also need to figure out how to convert opto sensors into accepting the switches I currently have for my pinball machine for pinball drain and ball location for example. If I can get over that last hurtle, then I can turn this project into a completed reality.