Patent · US Expired

Microcomputer having CPU and built-in flash memory that is rewritable under control of the CPU analyzing a command supplied from an external device

US5687345A · kind A · utility

39Cited by
30References
9Claims
0Family size

Assignees

Inventors

Key dates

Filing dateAug 21, 1995
Grant dateNov 11, 1997
Priority date
Expiry dateAug 21, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B69/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data processing apparatus having a built-in flash memory and being capable of performing a rewriting operation of the built-in flash memory, by use of versatilely used PROM writer, has a CPU, an electrically rewritable nonvolatile flash memory both formed in a single semiconductor substrate, and is operable in a mode in which the built-in flash memory is rewritable in accordance with commands supplied from a PROM writer. The data processing apparatus has a command latch which is externally writable when the above-mentioned operation mode is established, a command analyzer, that is, a command decoder, and a sequence controller for controlling a sequence of a rewriting operation of the flash memory in accordance with the decoded output of the command analyzer. The command analyzer and sequence controller may be realized by the CPU.

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