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:
May. 12, 1998
Filed:
Jun. 08, 1995
James J Jirgal, Chandler, AZ (US);
VLSI Technology, Inc., San Jose, CA (US);
Abstract
The present invention relates to an apparatus and method for supporting DMA I/O devices on a PCI bus. A DMA I/O device is coupled to a DMA controller via a serial link and two signal lines. The serial link is used by the DMA I/O device to request a DMA transfer. When the DMA controller receives the serialized DMA request, it sends a signal to an arbiter and waits for the PCI bus to be granted to the DMA controller for use during the DMA transfer. When granted the PCI bus, the DMA controller signals the DMA I/O device. The DMA I/O device asserts a signal in response to the one asserted by the DMA controller. The DMA controller recognizes the signal asserted by the DMA I/O device and continues with the DMA transfer. The transfer continues for as long as the DMA I/O device continues to assert the signal or for as long as the DMA controller is programmed.