# Episode 450 - Interview with Gerry Stellenberg 6-26-19 **Source:** For Amusement Only EM and Bingo Pinball Podcast **Type:** podcast_episode **Published:** 2019-06-27 **Duration:** 80m 11s **Beat:** Pinball **URL:** https://foramusementonly.libsyn.com/episode-450-interview-with-gerry-stellenberg-6-26-19 --- ## Analysis Gerry Stellenberg presents a seminar on custom pinball software development using the P-ROC board and Mission Pinball Framework. He explains how these tools simplify writing custom code for pinball machines across multiple hardware generations (WPC, White Star, Spike), eliminating the need for deep hardware expertise. The presentation covers the P-ROC's architecture, its independence from game logic, connection to external computers via USB, and driver management capabilities. ### Key Claims - [HIGH] P-ROC board is identical across WPC, WPC-95, and Stern (White Star/Spike) machines, differing only in mounting plates — _Gerry Stellenberg explaining board compatibility at pinballcontrollers.com seminar_ - [HIGH] Mission Pinball Framework is an open-source software development framework for custom pinball games — _Gerry Stellenberg introducing MPF as primary software tool alongside P-ROC_ - [HIGH] P-ROC manages all control circuits independently without running game code; game logic runs on external computer connected via USB — _Gerry Stellenberg explaining P-ROC architecture and USB connectivity_ - [HIGH] P-ROC supports 208 total drivers (32 direct pins + 176 multiplexed via ribbon cable) — _Gerry Stellenberg detailing driver specifications_ - [HIGH] Custom Judge Dredd machine with P-ROC was fully playable with voice, music, and sound effects after 10 months of development — _Gerry Stellenberg discussing live demo at pinball classics vendor area_ ### Notable Quotes > "hopefully by the end of today and I will convince you I'll show you that using a P-ROC board and a custom open source software development framework called Mission Pinball Framework that it's not nearly as complicated as you probably think" > — **Gerry Stellenberg**, opening remarks > _Core thesis: P-ROC/MPF democratizes custom pinball development by reducing complexity barrier_ > "the exact same board just a different metal plate so once you understand how to write code how to drop this into one machine you can do it on any generation machine" > — **Gerry Stellenberg**, hardware section > _Emphasizes cross-generation compatibility as major design win for P-ROC ecosystem_ > "yes I did say USB cable it doesn't need a parallel port you don't have to go out and find a motherboard that has some obscure port parallel port" > — **Gerry Stellenberg**, hardware architecture section > _USB connectivity removes major practical barrier for homebrew developers vs. older WPC systems_ > "the P-ROC stands for Pinball Remote Operations Controller and what it does is it independently manages all of the control circuits on a pinball machine" > — **Gerry Stellenberg**, P-ROC explanation > _Defines core P-ROC philosophy: hardware management decoupled from game logic_ ### Entities | Name | Type | Context | |------|------|---------| | Gerry Stellenberg | person | P-ROC board designer/developer, running pinballcontrollers.com, presenting seminar on custom pinball software | | Adam Preble | person | Co-host of For Amusement Only podcast, introducing Gerry Stellenberg | | Mission Pinball Framework | product | Open-source Python-based software development framework for custom pinball games, works with P-ROC and other hardware | | P-ROC | product | Pinball Remote Operations Controller board; aftermarket control board for custom and homebrew pinball development, compatible with WPC/White Star/Spike machines | | pinballcontrollers.com | organization | Website run by Gerry Stellenberg hosting P-ROC resources, documentation, and community | | For Amusement Only EM and Bingo Pinball Podcast | organization | Podcast where this seminar was recorded (Episode 450) | | Rob Anthony | person | Provided Judge Dredd machine for P-ROC demo at pinball classics vendor area | | Judge Dredd | game | Classic pinball machine being used as live demo platform for P-ROC custom software showcase | | WPC | product | Williams Pinball Controller; pinball hardware generation from early WPC through WPC-95, supported by P-ROC | | White Star | product | Stern pinball hardware generation, supported by P-ROC with same board as WPC/Spike | | Spike | product | Modern Stern pinball hardware generation, supported by P-ROC with same board as WPC/White Star | ### Topics - **Primary:** Custom pinball software development tools and accessibility, P-ROC board architecture and cross-generation compatibility, Mission Pinball Framework as open-source game engine, Homebrew pinball machine development - **Secondary:** Hardware control systems and driver management in pinball, USB connectivity vs. legacy parallel port interfaces, Lowering barriers to entry for pinball customization ### Sentiment **Positive** (0.85) — Gerry Stellenberg is enthusiastic about P-ROC/MPF as democratizing tools for custom development. Tone is educational and encouraging, emphasizing how these tools make custom pinball development accessible to non-experts. No criticism or negativity detected. ### Signals - **[technology_signal]** P-ROC board design matured to support multiple hardware generations (WPC/White Star/Spike) with single circuit board and modular mounting plates (confidence: high) — Same board works across three pinball hardware generations with only mounting plate differences; USB connectivity removes need for legacy parallel ports - **[technology_signal]** Mission Pinball Framework positioned as accessible open-source alternative to proprietary pinball development systems (confidence: high) — Gerry Stellenberg emphasizes MPF lowers expertise barrier; framework is open-source and Python-based, designed for non-hardware-experts - **[community_signal]** Active homebrew pinball community using P-ROC/MPF for custom projects; seminar at major show (pinball classics vendor area) indicates mainstreaming of custom development (confidence: high) — Live Judge Dredd demo with mature custom code; boards available for sale; dedicated website (pinballcontrollers.com); seminar format suggests growing interest - **[design_innovation]** P-ROC achieves same codebase compatibility across three major pinball hardware platforms by abstracting driver/control layer (confidence: high) — Single board design with platform-specific mounting; software development process identical across WPC/White Star/Spike - **[content_signal]** Gerry Stellenberg conducting structured seminar on custom pinball software at major pinball show, including live demo and Q&A (confidence: high) — Episode 450 of For Amusement Only podcast; formal presentation with project goals, video showcase, hardware/software walkthroughs, live Judge Dredd demo - **[product_strategy]** P-ROC ecosystem strategy emphasizes open-source tools, accessibility, and community contribution to lower barriers for custom development (confidence: high) — Mission Pinball Framework is open-source; Gerry Stellenberg framing entire seminar around 'making it easier' and 'not requiring expertise'; boards sold directly to community --- ## Transcript my name is jerry stokenberg this is adam preble and we're going to talk today about writing custom software for a pinball machine if you've ever wanted to retheme or build a home brew machine or maybe you just want to change the rules on your existing machine we're going to talk about how to do that now if you've ever thought about doing custom pinball development before you've really had two options one is to use the existing cpu board and somehow write code for it get that down there or to use some kind of custom hardware interface that maybe you've designed and built yourself done your whole driver circuits and all those things both of those solutions as you can imagine are quite quite complicated you have to understand all the low-level interface logic for a minimal machine you have to know how to write code to interface to those things you have to be aware of all the timing and control signals for everything well hopefully by the end of today and i will convince you early show you that using a p-rock board and a custom open source software development framework called pi procame that it's not nearly as complicated as you probably think maybe it is but hopefully it's not to write custom software for promotion so the agenda for today i'll give you a couple project goals we have a couple showcases one we'll show in the beginning when we'll show you the end of some some actual real life implementations using these things we'll talk about the hardware we're talking about the software and at the end we'll have a questions answer session so if you have questions that come up during the presentation please hold them to the end i don't know exactly how tight will be for time so we'll try to get some questions and if we don't get to all your questions then we'll be around all day feel free to to hunt us down and ask us whatever it is so the goals of the project were pretty much what i said earlier to to make it easier to write custom software for pinball machine we want to make it so you don't have to be an expert in hardware and software and whatever else you you might have had to learn in the past to write custom software the other main goal was we wanted a platform that would work in a whole variety of generations of pinball machines specifically we were targeting wpc machines all the way from the early wpc through wpc 95 and both generations both recent generations of steering machines so all white star and all state machines we wanted to build a platform that would work the exact same way in all these generations of machines so before we get started going into the details a little quick video if you've ever been to the website pinballcontrollers.com which is the site i run for the prop board and you've probably come across this video but let's run through it it's just it's it's six to eight months old but it gives you a good introduction of using this hardware in the software to write custom software so that video was like i said together about i guess it's been about 10 months since we since we put that together it's everything you saw was was custom software so the light shows that the dmd displays everything we wrote from scratch and now we have all that stuff available so you can you can build on top of that we have a judged red machine rob anthony brought us and is letting us use his dread machine over in the pinball classics vendor area so we're going to be there all day showing the latest and greatest version of this one feel free to come over play ask questions i'll even have a couple boards for sale if you're interested in buying one at the end of the seminar but 10 months later we have a we have full voice calls music sound effects it's a fully playable game maybe a couple issues we have to work through still but but it's pretty mature so feel free to come back and check it out later this is a prep board and you'll notice maybe you can see it maybe you can't this is the exact same shape as a wpc cpu board similarly i have i have a wpc 95 version here and we also have a stern mounting plate so if you look on the back there's actually eight mounting holes this fits in both the white star machine and the sand machine so the same board all three of these are the exact same circuit board just a different metal plate so once you understand how to write code how to drop this into one machine you can do it on any any generation machine but specifically the p rock stands for pinball remote operations controller and what it does is it independently manages all of the control circuits on a pivot machine and by independently what i mean is once you configure this board with software you don't have to keep writing your software doesn't have to keep interacting with it once it's configured it'll it'll manage all the hardware in your machine it'll manage the switch matrix it'll manage the interface to the driver boards it'll it'll manage it.matrix display and it does this automatically but it doesn't run code there's no cpu on this board there's no processing element it doesn't run your software so where do you rules code go where do you where do you put the code to run your game when you connect it to some sort of an external computer whether it's a a tower computer or you can even use a credit card size single board computer as long as this thing has a processing element and a usb connection you can hook it up so probably most people want someday to take a little credit card size single board computer drop it in their backbox no one will ever know that it's not running some stock hardware setup and yes i did say usb cable it doesn't need a parallel port you don't need to go out and find a motherboard that has some obscure port parallel port i know that's that's an issue for a lot of a lot of homebrew designers just finding motherboards that they can still use because they're using a parallel port like i said the board itself manages all the hardware control systems on the pinball machine and we'll go through each one of these individually so the drivers i'm calling drivers the things that drive all your coils lamps flashers motors all the playfield features in the machine the p-rock supports 208 drivers and most of you don't really care about all these details but if anyone's building a homebrew machine you're going to want to understand what the hardware can do and what features you can drive so 32direct there are 32 individual pins in this board that you can directly connect to transistor circuits oh by the way this board does not have all the transistors all the things that sit on the power driver board you connect this directly to the existing power driver aboard your machine or if you're building a homebrew machine you need to need to figure out a way to drive your actual coils and things design your own border or drop in an off-the-shelf wpc or power driver board so it's got the 32 direct it's got 176 multiplexed and by multiplex i mean you can access them using the ribbon cable that generally goes from the cpu board to the power driver board so we can we can control a whole bunch of drivers and the way we control those is the hardware exposes a bunch of functions that software can call so you don't need to write code to individually turn on and off every lamp every flash or every coil whenever you want to do this although you can that's the first function but we also have functions like a timed function so you can pulse a coil for however long you want 30 milliseconds 100 milliseconds just send the command saying pause the coil you can you could do if you say you want to blink a lamp _(Acquisition: youtube_mirror_subs, Enrichment: v3)_ --- *Exported from Journalist Tool on 2026-04-13 | Item ID: ccf5a264-e661-4798-ad17-5400900ea183*