Browse Prior Art Database

Method for Displaying Removable Media Device and Storage Cell Status

IP.com Disclosure Number: IPCOM000112675D
Original Publication Date: 1994-Jun-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 103K

Publishing Venue

IBM

Related People

Cummings, KD: AUTHOR [+2]

Abstract

A method for communicating device activity, storage cell "ownership", and operator intervention requests with a limited number of indicators on a removable media data storage system is disclosed. Indicators associated with storage cells are coded by color and flash rate to differentiate the various states.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 50% of the total text.

Method for Displaying Removable Media Device and Storage Cell Status

      A method for communicating device activity, storage cell
"ownership", and operator intervention requests with a limited number
of indicators on a removable media data storage system is disclosed.
Indicators associated with storage cells are coded by color and flash
rate to differentiate the various states.

      Automatic cartridge loaders and removable media data libraries
include the following elements:  a collection of storage cells that
hold media, a read/write device (e.g., a tape drive or an optical
disk drive), and a designated port or cell for inputting media to the
drive and outputting media from the drive.  Storage cells are used to
hold media until needed by the drive.  When a cartridge is needed, it
is automatically moved from a cell and inserted into the drive.  In
some implementations, the cartridge may be returned to its original
cell when the drive has finished processing it.  In some
implementations, operators have direct access to both the
input/output cell and storage cells, and may add or remove cartridges
at any time.

      Operators of such devices need to know about the status of the
drive, the input/out cell, and the individual storage cells.  Status
information should reflect the following conditions:

o   A cell (either storage or input/output) is reserved for a
    cartridge that is currently in use by the drive.  This informs
    the operator not to insert a cartridge into that cell.

o   The drive is in use (e.g., reading or writing data).  This
    operator can use this information to confirm that an activity is
    continuing.

o   Operator intervention is required at a particular cell (e.g., to
    remove a processed cartridge or insert a cartridge in a cell).
    In some instances it may be useful to signal different degrees of
    urgency.

      A method is disclosed for providing this status information
with a limited number of indicators.  In this method, each cartridge
cell (the input/output cell and the storage cells) is associated with
a two-color (e.g., yellow/green) Light-Emitting Diode (LED).  The
following states are indicated as described:

o   Cell in use:  When a cartridge is taken from a cell for transport
    to the drive, the cell indicator is lit green (steady-state on).
    This signifies that the cell is in use and that a cartridge will
    eventually be returned to that cell.  The operator should not
    insert a cartridge in the cell as long as the indicator is green.

o   Drive selected:  When a drive is selected by the host for read or
    write operations, the cell indicator marked "in use" flickers at
    a rapid rate (e.g., 4 hertz with a duty cycle of 67% on and 33%
    off).  The rapid flash rate is intended to simulate the "busy" or
    "selected" indicators common to tape and disk drives.  Because
    the indicator is fl...