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EXP Connection FAST Serial Protocol reference

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, we have a series of programming guides. Also, be sure to read the overview of how FSP works and how to connect first.

General commands

  • BR: Reset the expansion board
  • EA: Set the active expansion or breakout board
  • ID: Get the ID: response of an expansion or breakout board


  • EM: Configure the motor settings (including the type: servo, stepper, motor, etc.)
  • MP: Move the motor to a specific position

LED Commands for EXP Bus LEDs

  • RA: Set all LEDs on an expansion or breakout board to a certain color
  • RD: Set individual LEDs to be a certain color, binary command version
  • RF: Set the default fade rate for all LEDs on an expansion board
  • RL: Set individual LEDs to be a certain color over time (with fade), binary version
  • RS: Set individual LEDs to be a certain color

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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