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:
Nov. 02, 1999
Filed:
Nov. 05, 1997
Sergio Zigras, Paramus, NJ (US);
Timeplex, Inc., Woodclif Lake, NJ (US);
Abstract
A quad-port random access memory (RAM) is accessed simultaneously by a input-output (I/O) device, a digital signal processor (DSP), and a system bus with no need for any request/granted handshake. The I/O device, DSP, and system bus all constitute respectively different data transferring devices. The RAM is provided with three memory pages which are rotated logically by 120 degrees during successive time slots. The first memory page is accessed by the I/O device, the second memory page is accessed by the DSP, and the third memory page is accessed by the system bus during a first time slot. During subsequent time slots, the memory pages of the RAM are rotated logically so that data transfer is stepped through a predetermined sequence of data transferring device and memory page combinations in successive time slots so that all three data transferring devices are permitted to access the RAM at all times. The sequence continues repetitively during subsequent time slots. Data transmission and reception use opposite rotation directions and opposite device and memory page combinations.