POWER MODE OPERATION OF A MAGNETIC TAPE DRIVE

• US 20110102938A1
• Filed: 11/05/2009
• Published: 05/05/2011
• Est. Priority Date: 11/05/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: NAKAYAMA, HIROKAZU, DOAN, RANDALL S., JANGABA, FAHNMUSA C., MATSUO, HISATO, BATES, ALLEN K., HAGIWARA, KATSUHIKO, KNIBLOE, CHRISTINE R., NISHIDA, MITSUHIRO, BENTLEY, STEVEN R., WINARSKI, DANIEL J.
• Granted Patent: US 8,484,412 B2
• Time in Patent Office: Days
• US Class Current: 360/78.02
• CPC Class Codes: G11B 15/026 by using processor, e.g. microcomputer

Abstract

A magnetic tape drive having a tape drive system for moving magnetic tape, tape read/write and servo system, tape cartridge load/unload systems, I/O communications, memory; and a control system, operates in three modes to conserve energy consumption. A first low power mode powers the I/O communications, the memory, and the control system. If a magnetic tape cartridge is in loaded position in the magnetic tape drive, the second low power mode powers the same as the first low power mode, and additionally powers the tape drive system to apply tension to a magnetic tape of the magnetic tape cartridge. In the first and the second low power modes, the control system operates the I/O communications, the memory and the control system to respond to and execute commands received at the I/O communications if the commands are executable without magnetic tape access. The third, full power mode, is entered if a command received at the I/O communications requires magnetic tape access.

Claims

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 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;

operating said magnetic tape drive in a second low power mode if a magnetic tape cartridge is in loaded position in said magnetic tape drive, said second low power mode the same as said first low power mode, and additionally powering said tape drive system to apply tension to a magnetic tape of said magnetic tape cartridge;

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; and

operating said magnetic tape drive in a full power mode, if a command received at said I/O communications requires magnetic tape access.

2. The method of claim 1, operating said magnetic tape drive in said low power modes to respond to said received commands in a manner to emulate an active magnetic tape drive.

3. The method of claim 1, wherein said commands that are executable without requiring magnetic tape access comprise commands relating to data stored in said memory, to storing data in said memory, and relating to status of said magnetic tape drive.

4. The method of claim 1, further comprising:

analyzing commands received by said I/O communications when said magnetic tape drive is in one of said low power modes;

determining whether at least one said received command relates to at least one of data stored in said memory, data that may be stored in said memory, and status of said magnetic tape drive;

if so, executing said at least one command without powering on the remainder of said magnetic tape drive; and

if said command relates to at least one of data stored on a magnetic tape cartridge, to data that may be stored in said memory and exceeds the capacity of said memory; and

to action requiring movement of a magnetic tape, powering on said magnetic tape drive.

5. The method of claim 1, comprising, in said low power modes, powering off portions of said control system that are used with or control functions of said magnetic tape drive that are powered off.

6. The method of claim 1, comprising, when said magnetic tape drive is fully powered, if a magnetic tape cartridge is loaded but there is no tape movement for a predetermined time, to power down to said second low power mode.

7. A control and I/O system for a magnetic tape drive, said magnetic tape drive additionally comprising tape drive system, tape read/write and servo system, and tape cartridge load/unload system, said control and I/O system comprising:

I/O communications;

memory; and

control system configured to

operate 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;

operate said magnetic tape drive in a second low power mode if a magnetic tape cartridge is in loaded position in said magnetic tape drive, said second low power mode the same as said first low power mode, and additionally power said tape drive system to apply tension to a magnetic tape of said magnetic tape cartridge;

in said first and said second low power modes, operate 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; and

operate said magnetic tape drive in a full power mode, if a command received at said I/O communications requires magnetic tape access.

8. The control and I/O system of claim 7, wherein said control system is configured to operate said magnetic tape drive in said low power modes to respond to said received commands in a manner to emulate an active magnetic tape drive.

9. The control and I/O system of claim 7, wherein said commands that are executable without requiring magnetic tape access comprise commands relating to data stored in said memory, to storing data in said memory, and relating to status of said magnetic tape drive.

10. A control and I/O system for a magnetic tape drive, said magnetic tape drive additionally comprising tape drive system, tape read/write and servo system, and tape cartridge load/unload system, said control and I/O system comprising:

I/O communications;

memory;

power system; and

control system configured to;

operate said power system to place said magnetic tape drive in low power modes;

if said magnetic tape drive is empty, operate said magnetic tape drive in a 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, operate said magnetic tape drive in a second low power mode, said second low power mode the same as said first low power mode, and additionally powering said tape drive system to apply tension to a magnetic tape of said magnetic tape cartridge;

analyze commands received by said I/O communications when said magnetic tape drive is in one of said low power modes;

determine whether at least one said received command relates to at least one of data stored in said memory, storing data in said memory, and status of said magnetic tape drive;

if so, execute said at least one command without powering on the remainder of said magnetic tape drive; and

if said command relates to at least one of data stored on a magnetic tape cartridge, to data that may be stored in said memory and exceeds the capacity of said memory; and

to action requiring movement of a magnetic tape, operate said power system to power on said magnetic tape drive.

11. The control and I/O system of claim 10, wherein said control system is configured to operate said magnetic tape drive in said low power modes to respond to said received commands in a manner to emulate an active magnetic tape drive.

12. The control and I/O system of claim 11, wherein said power system, in said low power modes, powers off portions of said control system that are used with or control functions of said magnetic tape drive that are powered off.

13. The control and I/O system of claim 10, wherein said control system is configured, when said magnetic tape drive is fully powered, if a magnetic tape cartridge is loaded but there is no tape movement for a predetermined time, to power down to said second low power mode.

14. A magnetic tape drive comprising:

I/O communications;

memory;

tape drive system;

tape read/write and servo system;

tape cartridge load/unload system; and

control system configured to;

operate 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;

operate said magnetic tape drive in a second low power mode if a magnetic tape cartridge is in loaded position in said magnetic tape drive, said second low power mode the same as said first low power mode, and additionally power said tape drive system to apply tension to a magnetic tape of said magnetic tape cartridge;

in said first and said second low power modes, operate 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; and

operate said magnetic tape drive in a full power mode, if a command received at said I/O communications requires magnetic tape access.

15. The magnetic tape drive of claim 14, wherein said control system is configured to:

analyze commands received by said I/O communications when said magnetic tape drive is in one of said low power modes;

determine whether at least one said received command relates to at least one of data stored in said memory, storing data in said memory, and status of said magnetic tape drive;

if so, execute said at least one command without powering on the remainder of said magnetic tape drive; and

if said command relates to at least one of data stored on a magnetic tape cartridge, to data that may be stored in said memory and exceeds the capacity of said memory; and

to action requiring movement of a magnetic tape, power on said magnetic tape drive.

16. The magnetic tape drive of claim 15, wherein said control system is configured to operate said magnetic tape drive in said low power modes to respond to said received commands in a manner to emulate an active magnetic tape drive

17. The magnetic tape drive of claim 16, wherein said control system, in said low power modes, powers off portions of said control system that are used with or control functions of said magnetic tape drive that are powered off.

18. The magnetic tape drive of claim 15, wherein said control system is configured, when said magnetic tape drive is fully powered, if a magnetic tape cartridge is loaded but there is no tape movement for a predetermined time, to power down to said second low power mode.

19. The magnetic tape drive of claim 15, wherein said commands that are executable without requiring magnetic tape access comprise commands relating to data stored in said memory, to data that may be stored in said memory, and relating to status of said magnetic tape drive.