A data system 102 permits bus encoding based on frequency of the bus; an encoding scheme may be implemented to avoid undesirable frequency conditions such as a resonant condition that may lead to degradation in system performance. Address-translated packets are thus forwarded through a single-source multicast channel and received by the subscribing hostclients as though the packets came from a single \u201cvirtual\u201d source. An accurate measure of motor RPM is required for such control. A pulse width modulation signal is generated in response to the modified data. More specifically, it provides a process for producing methylcobalamin by reducing cyanocobalamin or hydroxocobalamin in the presence of a reducing agent, and then methylating the reductant by adding a water-soluble methylating agent.