This documentation is for an unreleased version of MPF!

This is the developer documentation for MPF 0.54, which is the “dev” (next) release of MPF that is a work-in-progress. Use the “Read the Docs” link in the lower left corner to view the developer docs for the version of MPF you’re using.

monitor_start (BCP command)

New in version 0.33.

Request from the media controller to the pin controller to begin monitoring events in the specified category. Events will not be automatically sent to the media controller from the pin controller via BCP unless they are requested using the monitor_start or register_trigger commands.


Media controller



Single string value, type: one of the following options: events, devices, machine_vars, player_vars, switches, modes, ball, or timer.

The value of category determines the category of events to begin monitoring. Options for category are:

  • events - All events in the pin controller
  • devices - All device state changes
  • machine_vars - All machine variable changes
  • player_vars - All player variable changes
  • switches - All switch state changes
  • modes - All mode events (start, stop)
  • core_events - Core MPF events (ball handing, player turn, etc.)