Memory states of a multi-bit memory cell are demarcated by generating read reference signals having levels that constitute boundaries of the memory states. The carrier head includes a housing, a base, a loading mechanism, a gimbal mechanism, and a substrate backing assembly. An inner balloon layer is placed adjacent the outer balloon layers and heat-sealed to one of them to form an enclosed pocket. The capabilities, preferences, andor settings may comprise multimedia processing capabilities, preferences, andor settings, communication capabilities, preferences, andor settings, andor power conditions, preferences, andor settings.