A method of operating an end effector of a surgical instrument includes supplying voltage to a motor disposed in a transmission mechanism of a surgical instrument having a shaft and an end effector at a distal end of the shaft; moving a component of the end effector between a first position and a second position via a drive system coupled to the motor; and placing a limit switch in a first state during moving of the end effector component, and in a second state when the end effector component is at one of the first position or the second position.