Abstract: The present invention comprises positive/negative masking signals which are added to an electronic circuit where ring phenomena may happen during high speed transmission of digital data, so as to eliminate the ring effect, and data can be transferred smoothly. Since the present invention uses only digital electronic circuit to solve the ring effect of related signals, no matter how long the cable between different subsystems is, the ring effect can be masked automatically. The problem of impedance matching is not necessarily considered, so the present invention is very valuable.

Abstract: In a memory management method for a computer with a hard disk drive, the hard disk drive is first partitioned into at least one system disk drive for storing system files therein, a data disk drive, a system buffer space and a read/write table. Thereafter, the computer is selectively operated in one of an unrestricted mode, where storing of the system files and modifying of the system files in the system disk drive by the computer are permitted, and a restricted mode, where modified portions of the system files in the system disk drive are stored by the computer in the system buffer space instead of the system disk drive to maintain the system files in the system disk drive in their initial form and where the read/write table is updated by the computer to record addresses of the modified portions in the system buffer space and addresses of portions of the system files in the system disk drive corresponding to the modified portions therein.