Processor system with dual clock

Details Processor system with dual clock Processor system with dual clock

1992-03-09

1994-06-28

Richardson, Robert L.

G06F 1300

Patent

active

053255160

ABSTRACT:
The present invention provides a means for operating the CPU in a single chip microprocessor at a multipe of the cycle speed of the memory bus. With the present invention, first and second timing signals are provided. The frequency of the second timing signal is a multiple of the frequency of the first timing signal. The second or fast timing signal is provided to the CPU and the first or slower timing signal is provided to the memory subsystem. A bus interface unit is interposed between the CPU and the memory bus. This bus interface unit receives the RDY signal (i.e. the ready signal) from the memory subsystem and modifies it before it is provided to the CPU. The "ready" signal from the memory subsystem is in an undefined state for a significant portion of each bus cycle. Since at least two CPU cycles occur during each memory access, the bus interface unit must ensure that the CPU does not misinterpret the ready signal from the memory subsystem. The bus interface unit also must modify the ADS signal (i.e. the address status signal) generated by the CPU. The ADS and RDY signals must be modified in a first way if the CPU calls for a memory cycle at the beginning of a bus cycle and in a second way if the CPU calls for a memory cycle in the middle of a CPU cycle. The use of a CPU clock speed doubler in combination with a write-back cache achieves truly synergistic increases in system speed.

REFERENCES:
patent: 3703707 (1972-11-01), Bovett
patent: 5179667 (1993-01-01), Iyer
PC Magazine, vol. 11, No. 3, p. 113, Feb. 11, 1992.
PC Magazine, vol. 10, No. 16, p. 37, Sep. 24, 1991.
PC Week, vol. 8, No. 40, p. 12, Oct. 7, 1991.

Affiliated with

Also associated with

Rating

Processor system with dual clock does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Processor system with dual clock, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Processor system with dual clock will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2383488