Recording heads for a data storage system include a first diode, a second diode, and a first electrical component. In accordance with the present addition method, the mantissa of a first floating-point operand is shifted in accordance with relative operand exponent information. A channel structure is formed along the substrate, having source and drain structures laterally formed on opposites sides thereof. The power regulation module is used for generating a power supply specification according to the electrical energy. In another embodiment, the frequency of transmission for the quality messages is determined by the channel quality. This information may be correlated to customer satisfaction and used identify particular strengths and weaknesses in the shopping experience offered by a store.