Browse Prior Art Database

Impending Device Removal Detection for Personal Computer Memory Card International Association Disk Drives

IP.com Disclosure Number: IPCOM000113532D
Original Publication Date: 1994-Sep-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 56K

Publishing Venue

IBM

Related People

Larson, TS: AUTHOR [+2]

Abstract

Described is a method to detect the impending removal of a small Direct Access Storage Device (DASD) from its host connector interface in order to allow sufficient time for actuator retract and head unloading if necessary.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 68% of the total text.

Impending Device Removal Detection for Personal Computer Memory Card
International Association Disk Drives

      Described is a method to detect the impending removal of a
small Direct Access Storage Device (DASD) from its host connector
interface in order to allow sufficient time for actuator retract and
head unloading if necessary.

      This invention uses a small switch either in the DASD or in the
connector attached to the host.  The switch is designed so that it
opens (or closes) before the power is lost when removing the file
from the connector.  The switching action can be provided as shown in
Fig. 1.  A small dimple on the DASD body engages a switch in the
female connector housing which is part of the host (e.g., computer).
The switch and dimple are designed so that, as a file is disengaged
from the host connector, the switch action occurs before power
interruption takes place.  This allows time for actuator retract and
head unload.

      The invention also handles cases when the file is writing data
when it is abruptly removed.  The knowledge that the file will
shortly lose power invokes an interrupt routine in the file
microprocessor program that performs the necessary housekeeping so
that data is not lost.

      The file electronics are notified of the impending removal by
using the card detect pins CD1 and CD2, in the case of Personal
Computer Memory Card International Association (PCMCIA) connectors,
which are located at opposite ends o...