Patent · US Expired

Microprogrammed programmable controller

US4266281A · kind A · utility

24Cited by
8References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 2, 1979
Grant dateMay 5, 1981
Priority date
Expiry dateApr 2, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/15103
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A programmable controller includes a processor formed around a pair of four-bit bipolar microprocessors. A control program formed by selected macroinstructions is stored in a random access memory and it is executed by sequentially mapping each macroinstruction operation code into a corresponding microroutine which is stored in a read-only memory. Some macroinstructions include operand addresses of a line in an I/O image and data table portion of the random access memory, and one macroinstruction (ADX) expands this operand address to enable the I/O image and data table to be expanded in size. A timer macroinstruction is executed in part by reading the state of a counter which is driven by a real time clock, and arithmetic functions are performed with the use of a decimal adjust accumulator.

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