| 摘要 |
A simple method and circuit for qualifying and combining individual request signals received from a plurality of disk drives within a disk array to generate a single, synchronized request signal for the disk array. The circuit includes an activity register for storing a bit pattern which identifies those disk drives which are in use within the array. Each bit position within the activity corresponds to a different disk drive within the disk array. A logic one stored in a bit position identifies the disk drive corresponding to the bit position as being active while a logic zero stored in a bit position identifies the disk drive corresponding to the bit position as being inactive. The circuit further includes an OR gate associated with each disk drive within the disk array, each OR gate having a first input connected to receive the bit information corresponding to its associated disk drive from the activity register, and a second inverting input for receiving the individual request signal from its associated disk drive. The outputs of the OR gates are provided to an AND logic operator which combines the received signals to generate the request signal for the array. Additionally, the circuit includes a NAND gate associated with each disk drive within the disk array. Each NAND gate has a first input connected to receive the bit corresponding to its associated disk drive from the activity register, and a second input for receiving an acknowledge signal for the disk array. The NAND gates function to provide individual acknowledge signals to the active disk drives within the array.
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