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This is a config file reference. Click for instructions.

This page is reference material which explains every setting and option for this section of an MPF yaml config file. See the instructions for config files for formatting and other details. See our guide to config file examples for more examples of real configs in action.

Valid in
machine config files YES ✅
mode config files NO 🚫

The machine: section of your config is where you configure defails about the number of balls in your machine.

  balls_installed: 6
  min_balls: 3

Optional settings

The following sections are optional in the machine: section of your config. (If you don't include them, the default will be used).


Single value, type: integer. Default: 1

The (maximum) number of balls which should be installed in your machine.


Single value, type: integer. Default: 1

The minimum number of balls required to start a game. If less than min_balls are present MPF will refuse to stat a game.

It's super annoying if you walk up to a pinball machine on location and can't start a game because it's missing a ball. So this setting lets you specify the minimum number of balls that need to be installed in order for a game to start. Note that it's up to you to make sure your game code can handle fewer balls than you might be expecting.

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