Patent · US Expired

Protection system for critical memory information

US5668973A · kind A · utility

21Cited by
33References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1995
Grant dateSep 16, 1997
Priority date
Expiry dateApr 14, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07B2017/00967
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A computer system for protecting memory comprising a processor having address outputs and executing a stored program, a memory having a control input, an address-decoder for providing a control signal to the control input of the memory in response to associated address outputs from the processor, and a window circuit. The window circuit comprises a range detector responsive to the address outputs for generating a range-detection signal indicative of an address from the processor being within a protected range, the protected range non-identical to the entirety of the space of addresses within the memory. Access to memory locations within the protected range is permitted only if a request signal is received from the processor. If the request signal is asserted for an unexpectedly long time an error condition is annunciated, for example the processor is reset.

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