Patent ID: 6862643

Claim:
A USB compound device, utilized to connect a plurality of function devices to a USB Bus and make the connected function have the advantage of “plug-and-play” function, comprising: a USB transceiver for utilizing as the connection point between the plurality function devices and the USB Bus, transmitting signals to or receiving signals from the USB Bus and performing the signal format conversion; a serial interface engine (SIE) for decoding the signals received from the USB Bus and then transforming them from serial form into parallel form, coding the signals to be transmitted to the USB Bus after transforming them from parallel form into serial form, and performing cyclic redundancy check code inspection while transmitting/receiving; and a circuitry for storing and managing a plurality of device addresses designated by a USB host, and proceeding with data transmission, wherein said circuitry does not have the functions of said USB transceiver and said SIE, and its one terminal is connected to said SIE while the other terminal is connected to a plurality of non-USB interfaces, which are used to connect to the plural function devices, via a microprocessor or controller.