Surgical power tool with critical error handler

A method for monitoring the operation of a surgical power tool, the surgical power tool including a plurality of components positioned in or on a housing, the method comprising:

• with a controller, periodically interrogating the plurality of components to determine if any of the plurality of components are in a fault condition;
• and
• when at least one of the plurality of components is in a fault condition, engaging a critical error handler that:
• disables at least one of the plurality of components, and
• directs a microprocessor in the controller into a safe software state.

A surgical power tool, comprising:

• a housing;
• a controller positioned in the housing;
• a battery configured to supply electrical power to the controller;
• a trigger coupled to the controller and configured to turn on a first component of a plurality of components when the trigger is depressed and adjust a speed of the first component based on how far the trigger is depressed;
• and
• a mode switch coupled to the controller and configured to select among at least two specified modes of operation for the controller,
• wherein the controller, the battery, the trigger, and the mode switch are included in the plurality of components;
• and
• wherein the controller is configured to:
• repeatedly interrogate the plurality of components to determine if any of the plurality of components are in a fault condition;
• and
• when at least one of the plurality of components is in a fault condition, engage a critical error handler that:
• disables the trigger and the mode switch,
• directs a microprocessor in the controller into a safe software state, and
• causes a sound emitter to emit an audible alarm.