USB control circuit of a built-in signal junction circuit

Abstract

The invention provides a USB control circuit of a built-in signal junction circuit comprising an uplink media access control layer circuit; a downlink media access control layer circuit; a first USB physical layer circuit; a second USB physical layer circuit; a first switching circuit which performs data communication with an uplink connecting port through the first USB physical layer circuit; a second switching circuit which performs data communication with a downlink connecting port through the second USB physical layer circuit; a control signal transportation interface; a signal junction circuit; a control unit which is used for controlling the first switching circuit and the second switching circuit through the control signal transmission interface so that the first switching circuit selectively couples the uplink media access control layer circuit or the signal junction circuit to the first USB physical layer circuit, and the second switching circuit selectively couples the downlink media access control layer circuit or the signal junction circuit to the second USB physical layer circuit. The roles of the USB concentrator connected to an OTG device can be elastically switched by the control unit to avoid the limited purpose of the OTG devices.

Description

technical field [0001] The invention relates to a USB control circuit, especially a USB control circuit with a built-in signal relay circuit. Background technique [0002] A USB hub device is a very common data transmission device, and its main function is to convert and distribute data between a USB host device (USB host device) and a USB peripheral device (USB peripheral device). The USB hub device includes an upstream port for connecting to a USB host device, and a downstream port for connecting to a USB peripheral device. [0003] The OTG (On-the-Go) function is defined in the supplementary specification of the USB protocol, which allows USB peripheral devices (also known as OTG devices) that support OTG functions to selectively play the role of USB master devices or The role of USB peripherals. Therefore, the OTG device is classified as a dual role device. [0004] However, the connection objects of the uplink port and the downlink port of the traditional USB hub dev...

AI Technical Summary

Problems solved by technology

[0004] However, the connection objects of the uplink port and the downlink port of the traditional USB hub device cannot be swapped, otherwise it will lead to the problem that normal data transmission cannot be performed between the USB master device and the USB peripheral device

For example, when an OTG device is connected to the uplink port of a traditional USB hub device, it can only be used as a USB master device, but cannot be used as a USB peripheral device

On the other hand, when an OTG device is connected to the downstream connection port of a traditional USB hub device, it can only be used as a USB peripheral device and cannot be used as a USB master device.

[0005] Therefore, when two OTG devices are respectively connected to the upstream connection port and the downstream connection port of the traditional USB hub device, the roles played by these two OTG devices are limited and cannot be reversed.

[0006] Obviously, the structure of the traditional USB hub device limits the use of the OTG device, and it cannot be switched according to actual needs to adapt to the role of the OTG device.

Images