Patent · US Expired

Address translation apparatus

US4218743A · kind A · utility

36Cited by
5References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 17, 1978
Grant dateAug 19, 1980
Priority date
Expiry dateJul 17, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/1081
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Address translation apparatus is provided for translating virtual addresses to real storage addresses and real storage addresses to virtual storage addresses. The address translation apparatus uses a page directory having a next real address and an associated virtual address ordered according to real addresses. This simplifies the manner in which the input/output (I/O) handles addressing in a virtual storage computer system. When the I/O device control mechanism needs to resolve the real I/O address register, it uses the contents of that register to index into the page directory to obtain a corresponding virtual address. The corresponding virtual address is incremented and converted to a real address which is used to index into the page directory. The virtual address taken from the page directory is then compared with the virtual address which had been incremented and translated. If the two compare then the real address which had been used to access the page directory is entered into a register so as to be available as a real main storage address. In actuality it is only a partial real main storage address and is concantenated with a byte identifier portion of the main storage addr…

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