METHOD AND SYSTEM FOR HIGH-SPEED DETECTION HANDSHAKE IN UNIVERSAL SERIAL BUS BASED DATA COMMUNICATION SYSTEM

摘要

A USB system includes a USB hub, a USB device, and a USB bus interconnecting the USB hub and the USB device. The USB hub asserts a reset signaling on the USB bus to initiate a high-speed detection handshake. The USB hub and the USB device activate corresponding dual-mode squelch detectors in a first (handshake) mode of operation. The USB device transmits a device chirp signal to the USB hub. The USB hub responds with a sequence of hub chirp signals. The USB device detects the hub chirp signals and then the USB hub and the USB device establish a communication link in a high-speed mode of communication in accordance with USB 2.0. The dual-mode squelch detectors in the USB hub and the USB device can also be activated in a second (normal) mode of operation.