A clock generator circuit is provided wherein a comparison clock signal is generated by comparing a standard clock signal and an operating clock signal. The invention facilitates autonomous and remote negotiation between sellers and prospective buyers while protecting buyers from fraud and item misrepresentation. The two power rails include an upper power rail and a lower power rail. There is a coating applied to the cutting tool. In a preferred embodiment of the invention, the inside surface of the panel is black to facilitate visual differentiation of similar yarn shades. The detected absolute rotational angle of the shaft is refined with the detected relative angular position of the shaft to thereby generate the absolute rotational angle of the shaft with more precision.