External clock unit for a computer

Abstract

An external clock unit for use with a DEC 6000 series computer for increasing the clock cycle time includes an oscillator for generating a clock signal which is faster than the clock signal produced by the oscillator in the CPU module in the computer, a line driver for driving the clock signal outputted by the oscillator in the clock unit, a manually operable switch for outputting a control signal and a power supply for providing power to the various components in the clock. In use, the external clock unit is connected to the clock distribution chip in the CPU module in the computer using pins normally used only for test purposes during fabrication. When the switch is turned on, the clock from the oscillator in the computer CPU module is disabled and the clock signal from the clock which is received by the clock distribution chip is used as the clock signal for the computer.

Dependencies are inferred from the claim text.