PC system having flash-ROM controlling device and method for protecting BIOS stored in flash-ROM

摘要

A device controlling a flash-read-only-memory (flash-ROM) storing a basic input output system (BIOS) of a personal computer including a controller controlled by software generating a first control signal or a second control signal controlling a chip enable signal of the flash-ROM, and a control buffer, having an input port receiving the chip enable signal and an output port connected to a chip enable port of the flash-ROM, outputting the chip enable signal unchanged when the control signal generated by the controller is the first control signal and changing the chip enable signal to be inactive and outputting the changed chip enable signal when the control signal generated by the controller is the second control signal.