Open Pinball Project (OPP)

What Is OPP?
Open Pinball Project
…a resource for pinball makers to have an inexpensive, fully open sourced project for controlling custom pinball machines.
Read more about it here, where I try to explain why I chose it: Why OPP?
OPP at Pinballmakers
https://pinballmakers.com/wiki/index.php?title=OPP#Open_Pinball_Project
OPP at Kickstarter
https://www.kickstarter.com/projects/507097900/open-pinball-project-open-source-pinball-hardware
OPP has a Wordpress Blog
https://openpinballproject.wordpress.com/
OPP at Sourceforge
https://sourceforge.net/projects/open-pinball-project/
OPP at Mission Pinball Framework
https://missionpinball.org/hardware/opp/
OPP at Mezel Mods (Circuit Boards)
https://mezelmods.com/collections/open-pinball-project-parts