Patent · US Expired

Synchronous clock stopper for microprocessor

US4545030A · kind A · utility

92Cited by
7References
4Claims
0Family size

Assignees

Inventor

Key dates

Filing dateSep 28, 1982
Grant dateOct 1, 1985
Priority date
Expiry dateSep 28, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F1/10
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A synchronous clock stopper circuit for inhibiting clock pulses to a microprocessor in response to a stop request signal, and for reinstating the clock pulses in response to a start request signal thereby to conserve power consumption of the microprocessor when used in an environment of limited power. The stopping and starting of the microprocessor is synchronized, by a phase tracker, with the occurrences of a predetermined phase in the instruction cycle of the microprocessor in which the I/O data and address lines of the microprocessor are of high impedance so that a shared memory connected to the I/O lines may be accessed by other peripheral devices. The starting and stopping occur when the microprocessor initiates and completes, respectively, an instruction, as well as before and after transferring data with a memory. Also, the phase tracker transmits phase information signals over a bus to other peripheral devices which signals identify the current operational phase of the microprocessor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.