Patent · US Expired

Operand size mechanism for control simplification

US4649477A · kind A · utility

8Cited by
1References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 27, 1985
Grant dateMar 10, 1987
Priority date
Expiry dateJun 27, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/30036
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data processor having size selector in a controller for explicitly selecting the size of an operand independent of an instruction in an instruction register, together with means for selectively enabling the instruction register or other functional block, or a size selector to select the size of the operand. A size bus and a size multiplexer are also provided to route the size instructions. By using this size mechanism, the amount of sequencing and control logic is significantly reduced from prior data processors. The mechanism allows operations of different sizes to be performed during a single instruction while allowing instruction dependent sizing to be done residually.

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