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Retro Controllers: FAST Serial Protocol Overview

FAST Serial Protocol: Overview & First Steps

This documentation section is about the FAST Serial Protocol (FSP) commands, which are the low-level commands a host computer sends to a FAST board. Most FAST Pinball makers do not need to know about these details, since the pinball game framework (such as the Mission Pinball Framework) handles this communication for you.

If you're writing your own game framework, read the overview of how FSP works and how to connect first.

This product is not yet released

This documentation is for a product that is not yet released. Final details may change.

When you connect to a FAST Retro Controller via USB, you will see multiple virtual serial ports appear. The exact port names and numbers will vary depending on your computer and which Retro Controller you have, but they will always be in the same relative order.

So we talk about the "first port" or "third port", and that could be:


Or it could be:

/dev/tty.usbmodem1101, /dev/tty.usbmodem1103, /dev/tty.usbmodem1105

One of the ports will connect to the EMU Processor to run the emulation. Another will connect to the NET Processor which is used to run the "modern" game software on the classic hardware.

Depending on your hardware, a third and/or fourth port might be available to connect to the EXP or DSP processors.

Documentation Feedback? Requests? Confused?

Hi! I'm Brian, and I'm responsible for the documentation at FAST Pinball. If you have any feedback, requests, corrections, ideas, or any other thoughts about this documentation, please let me know! You can email me at Thanks!

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