Old FRC Electronics


The FIRST Robotics Competition is a competition held anually in which high school teams, with corporate or college mentors, play some game remotely with robots. This is a really big series of events.

Teams that have been around a while collect a lot of old FIRST equipment, including custom electronics. While some parts are easily reusable for other things, the custom control electronics can't (officially) be used except as a complete system. This was bothering me, as I had access to several pairs of old FIRST radios that should havebeen usable for other projects.

IFI Control System Components

  • Field controller: Part of the field.  Sits between an OI and a field radio.  These are not generally available.
  • OI (Operator Interface): Monitors joysticks and other user inputs and generates data to send to the robot.
  • RC (Robot Controller): Mounted on the robot.  Runs code written by the team and provides outputs to motor drivers and other actuators.
  • Radios: The OI-side and RC-side radios differ only in the antenna style and which channels are used for transmit vs. receive.


  • Pre-2001: Very little information about this era.  Unreliable radios and some kind of BASIC stamp.
  • 2001-2003: The first major revision of the IFI control system.
  • 2004-2008: The second major revision.  More capable RC microcontroller (PIC18F452).  Minor OI and radio changes.  The radio was replaced in 2007 due to component obsolescence.
  • 2009-present: Total overhaul.  The robots now use National Instruments Compact RIO controllers and WiFi.  Vastly improved capabilities.