A microcontroller determines the position of the rotor of a brushless, direct-current motor by determining the time of zero crossing of back electromotive force emanating from the non-driven phase winding. The system has policies to implement an \u201cethical wall\u201d to separate users or groups of users. Each memory cell is coupled to both a read bit line and a write bit line. The third conductive portion is located between the first and second conductive portions.