Eric Conner Apps

Software Development • Electrical Design

Assembly Complete

After spending countless hours with a soldering iron over the past few days the first set of Retro-Pin boards are assembled. A few minor mistakes were found, silkscreen error, one trace that needed to be rerouted, and forgetting to add a 5v regulator to the power adapter board. All mistakes were easily fixed and will be corrected on future revisions. The boards have been mounted in a Firepower machine and are ready for testing.

Completed Retro-Pin boards mounted in Firepower

Retro-Pin Prototype PCBs

This week the prototype circuit boards arrived from OSHPark and as always they are perfect. Once these have been populated testing will begin and then the plan is to install the boards in Firepower and emulate the gameplay with our system. Once a fully playable game has been created and tested we will have a few beta test boards available.

Completed Retro-Pin Teensy 3.6 MPU

Pinduino is now Retro-Pin

I've always liked the Pinduino name but since there's another pinball related device using it and the domain name is already taken it's time for something unique. After spending a few weeks thinking and contemplating I've reached a decision, Retro-Pin. I feel like it follows the goal of the project, building custom pinball machines using existing retro games. In the future all information on this project can be found at

Pinduino Update

It's been a while since my last post about the Pinduino project. It's continuing to evolve into a full featured device even though progress has been slower than I had originally hoped. The hardware portion has seen some recent changes with a new microcontoller (Teensy 3.6) that required an update to the MPU board. The Teensy 3.6 has a built-in micro SD card reader and a DAC for audio playback so theres no need for an additional sound board for audio processing, thanks to The Ben Heck Show for the inspiration. The I/O Driver board has also been revised to better connect to any Williams System 3-7 machine with no modifications to the existing game. Another addition is a power adapter board so that the original Williams power supply can be used. I'm currently waiting for the new boards to arrive for testing.

Teensy 3.6

The Arduino library has also been revised to work with the new microcontoller. I've also began splitting each class into it's own file so the project will be easier to edit and maintain in the future. A basic sound class has been implemented allowing background music and sound effects to be played simultaneously.

Once the new boards and library have been tested the GitHub repository will be updated.

The Pinduino Project


The Pinduino project is a simplified control system for building your own pinball machine using the popular Arduino system.

  • 64 switch inputs
  • 64 lamp outputs
  • 16 to 32 solenoid outputs
  • 6 special solenoid outputs
  • 2 flipper outputs
  • 4 seven digit score displays
  • 1 credit/ball count displays
  • Sound card for playing WAV files
  • Must be simple to program new games

This is a dream that I've been working towards since 2012. After spending the weekend at the Allentown pinball show I decided to begin designing the initial prototype.


Over the years I would work a little at a time on the project only to be interrupted by something more important. I've finally found the time to complete it and have been progressing with leaps and bounds. Currently the project is 80% complete with 64 switch inputs, 64 lamp outputs, 16 solenoid outputs, 6 specail solenoid outputs, and 2 flipper outputs. The system also has an I/O Expansion port to add an additional 16 solenoid outputs and flipper outputs.


You can follow and contribute to the project on GitHub.

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