PERSONAL COMPUTER SYSTEM HAVING FLASH-ROM CONTROL DEVICE AND METHOD FOR CONTROLLING THE SAME

摘要

PURPOSE: A personal computer system having a Flash-ROM control device and a method for controlling the system are provided to prevent the remove of a BIOS recorded in a Flash-ROM besides a Flash-ROM manufacturer. CONSTITUTION: A control unit(302) has it's input/output address and directly controlled by a software as a ROM-BIOS and an application program and creates a control signal for controlling a chip enable signal being inputted to a Flash-ROM. The control signal includes the first control signal and the second control signal. The control unit(302) includes a decoder and a data storing unit. The decoder senses an input/output address allocated thereto from an address bus out of system buses of a personal computer. If the input/output address is sensed by the decoder, the data storing unit inputs a predetermined one byte from a data bus out of system buses of a personal computer and stores the byte, and outputs the stored data as a control signal. A control buffer(304) includes an input terminal for inputting the chip enable signal and an output terminal being connected to a chip enable terminal of the Flash-ROM. In case that the control signal created in the control unit(302) is the first control signal, the control buffer(304) outputs the inputted chip enable signal as it is. In case that the control signal created in the control unit(302) is the second control signal, the control buffer(304) converts the inputted chip enable signal into a deactivation state and outputs the converted signal. The chip enable signal of the Flash-ROM being inputted to the control buffer(304) is created in a PCI-ISA bridge(320).