It apparently has been about five years since I last wrote about me and my dad working a homebrew pinball machine. The idea at the time was to make a homebrew pinball machine based on a Bally Freedom EM pinball machine.


A lot has happened since that last post. The prototype has been teared down after it has been collecting dust for a while. The cabinet of the Bally Freedom EM machine was sold to someone who turned it into a virtual pinball machine. No new prototype, at least of a full scale pinball machine, has since been made.

Around that time I discovered the Blue Pill development board, based on the STM32F103C8T6 microcontroller. I wanted to use this microcontroller because of its CAN-bus interface. Little did I know that the act of buying a few of these boards would eventually end up being its own project called STM32-base.

Another big project we worked on was project Test-Case. This project took quite some work to get from prototype to a finished device. This might have been the project I personally learned most from.

And what about PinBus? Well, it never became the CAN-bus-based pinball controller platform I wanted it to be. However, it still might end up being a pinball controller platform one day. For now, I use the name to put on all the PCBs I design.

The new victim

The intent is still to make a homebrew pinball machine and it hasn’t gone away while working on all the other projects. The cool thing about working on the other projects is that I gained a lot of experience that will only support making a homebrew pinball machine.

So the new victim is a Gottlieb Pinball Pool machine. Again a machine that was in a really bad shape. And in addition to the machine’s own assemblies, we still have a bunch of assemblies from a Gottlieb Dragon machine.


The first thing to do is to refurbish the assemblies from the Pinball Pool machine and put them back on the original playfield. This will then become the another prototype, based on some older MOSFET driver boards we still have got laying around.

From this prototype we will continue developing the hardware and software to eventually be able to move on to designing a custom playfield which will incorporate a lot of the assemblies from both the Pinball Pool and Dragon machines.