Data in less than all of the pages of a non-volatile memory block are updated by programming the new data in unused pages of either the same or another block. One example apparatus includes a pre-driver circuit configured to provide a transition control signal responsive to received data, and a main driver circuit configured to drive an output node responsive to the transition control signal. The machines also include a brake mechanism having one or more braking components adapted to engage and stop the cutting tool in response to the detection of a dangerous condition. A compression spring is sleeved onto the shaft and stopped between a stop flange around the periphery of the shaft and the top wall of the axial sleeve. The core has a slot placed under said weld seam.