Abstract: A building-block system framework comprises a host device and a plurality of independently operable function devices, in which each device is provided with a conversion circuit (a codec and interface circuit, etc.) for converting signals into common standards (USB or IEEE1394, etc.), such that the signals can be transmitted to the host device and those function devices. The function devices could be a musical accompaniment, TV set, phonographic equipment (including an FM/AM receiver or amplifier), CD player, phone set, etc. The host device is supposed to run an indispensable operating software for controlling the function devices, by which a user could selectively operate the function devices according to the detection results showing whether a function device is existed or not.

Abstract: A method for control of multiple operating systems is applied to detect whether a Hard Disk Drive (HDD) is connected with a system bus of an electronic machine by using a Basic Input and Output System (BIOS). If the result is “true,” an operating system stored in the HDD will start the machine, otherwise, another operating system stored in a flash ROM (Read Only Memory) module will start the machine instead. The operating system in the flash ROM module serves a back-up system for booting the electronic machine in case of a HDD booting failure.