The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 30, 1999
Filed:
May. 31, 1995
Tetsuya Mochida, Yokohama, JP;
Hitoshi Kawaguchi, Yokohama, JP;
Kazushi Kobayashi, Ebina, JP;
Ichiharu Aburano, Hitachi, JP;
Takanori Ishikawa, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Process Computer Engineering, Inc., Hitachi, JP;
Abstract
In a computer system having an address converter for DMA (direct memory access), an address conversion apparatus in which a memory area to be accessed by the DMA can be accessed at high speed from a CPU. A 'DMA address conversion area' is defined in a memory space, and address conversion means in the mode of accessing the DMA address conversion area is so constructed that, when the area has been accessed from the CPU, a physical address is generated in accordance with the address conversion routine of the DMA address conversion means or converter, so as to access a main storage. The memory area to be accessed by the DMA can be quickly accessed from the CPU without requiring such an operation as especially accessing the control ware of the address converter or producing the physical address under the management of a program run on the CPU.