Patent · US Expired

Apparatus controlled by a micro-computer and including power loss data checking

US4750040A · kind A · utility

28Cited by
2References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 20, 1986
Grant dateJun 7, 1988
Priority date
Expiry dateAug 20, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03J1/0008
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Apparatus for use in a television receiver of the kind controlled by a micro-computer is intended for the situation in which power failures occur and specifically where instantaneous power failures occur and shortly thereafter the power is recovered, in which it is determined whether or not the time display data stored in a memory of the micro-computer is correct and, if so, such data is continued to be refreshed and is used for the time display, whereby a backup circuit is simplified in construction, and even eliminated in some cases. The main television receiver control data are stored in a nonvolatile memory when a power interruption occurs, but are only used to refresh the random access memory of the micro-computer in those instances where the power outage exists for a period of time long enough to erase the time display data retained in the random access memory, a condition that is determined by checking such time display data each time it is necessary to reset the central processing unit of the micro-computer in view of a drop in line voltage.

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