A CPU includes a register for setting a clock frequency and a frequency divider. The CPU sets an internal clock by frequency-dividing an externally supplied fundamental clock. A set of data set in the frequency setting register is selected through a setup menu displayed on a display unit. Of the data...http://www.google.fr/patents/US5479645?utm_source=gb-gplus-shareBrevet US5479645 - Portable computer capable of switching CPU clocks
