A magnetic induction time-multiplexed two-way short-range wireless communications system, and related method, includes a first portable unit and a second portable unit. The plate includes a plate member, a shaft supporting member that rotatably supports the main shaft, a motor mounting member on which the motor is mounted, and a flexible member that is provided between the shaft supporting member and the motor mounting member, enabling a relative movement of the shaft supporting member and the motor mounting member. The ARC layer is formed on a metal layer, wherein the lower percentage of silicon of the ARC layer inhibits the unwanted formation of suicides at the metal layerARC layer interface. The substrate may be planar or curved, and the open regions in the thin film material may be removed from deposited thin film material, or may be formed by preventing deposition of thin film material in such regions. Additionally, a method and system of mitigating firmware corruption is provided by flashing a boot block portion of device firmware only when an update is necessary.