Patent ID: 8484412
Filing Date: 2013-07-09
Classification: G11B

Abstract:
1. A method for operating a magnetic tape drive, said magnetic tape drive comprising I/O communications, memory, control system, tape drive system, tape read/write and servo system, and tape cartridge load/unload system, comprising the steps of: operating said magnetic tape drive in a full power mode if a magnetic tape cartridge is in loaded position in said magnetic tape drive with a magnetic tape threaded into said magnetic tape drive and said magnetic tape drive is active; operating said magnetic tape drive in a first low power mode if said magnetic tape drive is empty, said first low power mode comprising powering said I/O communications, said memory, and said control system; if a magnetic tape cartridge is in loaded position in said magnetic tape drive with a magnetic tape threaded into said magnetic tape drive, while in said full power mode, if said magnetic tape drive is inactive for a predetermined period of time, operating said magnetic tape drive in a second low power mode, said second low power mode comprising powering said I/O communications, said memory, and said control system, and additionally powering said tape drive system to apply tension to said magnetic tape of said magnetic tape cartridge without longitudinally moving said magnetic tape; in said first and said second low power modes, operating said I/O communications, said memory and said control system to respond to and execute commands received at said I/O communications if said commands are executable without magnetic tape access; analyzing commands received by said I/O communications when said magnetic tape drive is in one of said low power modes; if said command relates to at least one of data stored on a magnetic tape cartridge, and to action requiring movement of a loaded magnetic tape, powering on said magnetic tape drive to said full power mode; if said received command relates to at least one of data stored in said memory, to storing data in said memory and results in data that may be stored in said memory being within the capacity of said memory, and to status of said magnetic tape drive; executing said command without powering on the remainder of said magnetic tape drive; and if said received command relates to storing data in said memory and results in data that may be stored in said memory exceeding the capacity of said memory, powering on said magnetic tape drive to said full power mode.