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:
Sep. 28, 1999
Filed:
Oct. 29, 1997
David R Evoy, Tempe, AZ (US);
Lonnie Goff, Tempe, AZ (US);
Peter Chambers, Phoenix, AZ (US);
Mark Eidson, Tempe, AZ (US);
VLSI Technology, Inc., San Jose, CA (US);
Abstract
The system of the present invention comprises a system for implementing a real time capability in peripheral devices. The system of the present invention functions with a computer system including a processor, a memory, and a video controller, each coupled to a system bus. A USB (universal serial bus) controller is also coupled to the system bus for interfacing peripheral devices on a USB cable to the computer system. A first and second register are included in the USB controller for storing a controller frame number and a controller frame remaining, and a second and third register are included in the peripheral device for storing a device frame number and a device frame remaining. The peripheral device is coupled to the USB controller via a USB cable. A screen reference register is coupled to receive the controller frame number and the controller frame remaining from the USB controller and is coupled to receive a reference signal from a video controller. In response to receiving the reference signal, the screen reference register stores the controller frame number and the controller frame remaining. The peripheral device transmits the device frame number and the device frame remaining to the computer system in response to the occurrence of an event. The controller frame remaining and the controller frame number are subsequently compared with the device frame remaining and the device frame number to determine a computer system time (e.g., a real time) of the occurrence of the event.