Browse Prior Art Database

Load/Unload State Memory

IP.com Disclosure Number: IPCOM000123751D
Original Publication Date: 1999-Apr-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 1 page(s) / 27K

Publishing Venue

IBM

Related People

Ogasawara, K: AUTHOR [+4]

Abstract

This article describes an idea to log the history of the drive state, especially for the load/unload system in HDD.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Load/Unload State Memory

   This article describes an idea to log the history of the
drive state, especially for the load/unload system in HDD.

   The design of the system to prevent the head to land on
the disk is one of the most critical part in the Ramp Load/Unload
Technology.  In order to establish and brush-up this safety net
system, a new idea is proposed here which logs the drive state
history, and trace it later on failure analysis.  In general, "Head
land on the  disk" means head_to_disk stiction in Load/Unload HDD.
Thus the most useful information is the drive state just before the
Land on the Disk.  So
  1.  Will start to Load: Load Command has come
  2.  Unable to Load: Load Fail State
  3.  Load Completed: Head is on the rotational disk
  4.  Will start to Unload: Unload Command has come
  5.  Unable to Unload: Unload Fail State
  6.  Unload Complete: Head is on the Ramp should be stored
      for the information used later.  This invention
      proposes that those information to store on the non-volatile
      memory; such as EPROM.  By doing this, this information can
      be loaded from outside even if the head stuck on the disk.