A driving device is electrically connected with an AC power and a brushless DC motor for a fan. The communication system has a first node arranged to send data to a plurality of second nodes using a first protocol. The invention also provides a method for extracting contaminants involving the mixing method and apparatus suitable for carrying out the methods of the invention. At least one trench, which reaches into the substrate, is formed in the semiconductor body. Then, the functional block moves according the direction and distance stored in the mapped movement register. The electrical sensor and the optical sensor are used to calibrate the positions of one or more of: the sample platform, the reference platform, and a well.