Patent · US Expired

CPU Employing micro programmable control for use in a data processing system

US4323964A · kind A · utility

20Cited by
9References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 9, 1979
Grant dateApr 6, 1982
Priority date
Expiry dateOct 9, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/268
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A microprogrammed processor having a versatile hardware and data path configuration in which control signals for data paths, the ALU function, the shifter and all other control signals are derived from the current microprogram control word which is normally periodically clocked into a ROM buffer. Included are capabilities for effective addressing, incrementing the program counter and computer instruction skips, all while the instruction register is being loaded from memory by direct connection of selected bits of the memory bus to the ROM buffer to derive a micro-instruction. Also included is a conditional skip condition allowing the processor to skip the next instruction by testing selected bits of the instruction register which manipulates the micro-code for this purpose. Another capability is that of hardware structuring to readily accommodate WCS. Other capabilities provide for bit and byte manipulation, allowing the micro-instruction to readily load constants into the ALU, and for marking purposes. Data path connections provide for selective connection of the register file and the ALU output to the memory bus dependent upon existing memory bus and data bus communication with t…

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