Patent · US Expired

Circuit for reassigning the power-on processor in a multiprocessing system

US5627962A · kind A · utility

106Cited by
13References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 1994
Grant dateMay 6, 1997
Priority date
Expiry dateDec 30, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F11/1417
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A hot spare boot circuit that automatically switches from a non-operational CPU to an operational CPU for powering up the computer system. In the multiprocessor computer system, a first CPU is designated to perform power on operations. If the first CPU fails, which is determined when a dead man counter in the hot spare boot circuit times out, the hot spare circuit ensures that the first CPU is in a disabled state. Next, the hot spare boot circuit identifies an operational second CPU, reinitializing certain ID information as necessary such that the second CPU can properly perform power on operations. The hot spare boot then awakens the second CPU, using a startup interprocessor interrupt in one embodiment, or simply negating the hard reset of the second CPU in a second embodiment. The second CPU then proceeds to perform the power on functions.

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