Patent · US Expired

Data transfer controller incorporating direct memory access channels and address mapped input/output windows

US5142672A · kind A · utility

78Cited by
8References
91Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 15, 1987
Grant dateAug 25, 1992
Priority date
Expiry dateDec 15, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/28
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Methods and apparatus are disclosed for transferring data to and from a first bus, to which a first set of high performance devices, including at least one central processing unit ("CPU") is attached, and a second bus, to which a second set of relatively lower performance devices is attached. More particularly the invention accomplishes the above transfer function in a manner that facilitates communication between the first and second set of devices from the compartively lower performance of the second set of devices. According to the preferred embodiment of the invention, a data transfer controller i.e., ("DTC") is disclosed that includes a set of direct memory access ("DMA") channels and an input/output controller comprising a set of address mapped I/O ports. Both the DMA channels and I/O ports may be used to transfer data between the high performance channel (hereinafter referred to as the "Local Bus") coupled to the CPU in a reduced instruction set computer (RISC) system and a typically lower performance, peripheral bus (hereinafter referred to as a "Remote Bus"). The resulting DTC interface between the Local Bus and a Remote Bus permits a wide performance range of standard per…

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