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Error Injection Method for Testing Error Recovery Procedures

IP.com Disclosure Number: IPCOM000101922D
Original Publication Date: 1990-Sep-01
Included in the Prior Art Database: 2005-Mar-17
Document File: 2 page(s) / 73K

Publishing Venue

IBM

Related People

Osborne, SM: AUTHOR [+2]

Abstract

Described is a novel method for testing the error recovery procedures of disk drives. This method involves using a device to inject errors into the disk drive at will to observe the drive's error-handling capabilities. This method is illustrated by using this device for disk drives; however, it is also applicable to tape drives, testers, controllers, and other devices that contain error recovery procedures.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Error Injection Method for Testing Error Recovery Procedures

       Described is a novel method for testing the error
recovery procedures of disk drives.  This method involves using a
device to inject errors into the disk drive at will to observe the
drive's error-handling capabilities.  This method is illustrated by
using this device for disk drives; however, it is also applicable to
tape drives, testers, controllers, and other devices that contain
error recovery procedures.

      Since natural drive errors due to media defects are infrequent,
it is difficult to test the error recovery of these disk drives.
This device allows errors to be forced into the drive within a
certain sector for a specific duration of time.  After this error
occurs, additional errors can occur within that sector or other
sectors.  In this way, it is easy to derive a test pattern that will
include a certain number of errors or pattern of errors.  A block
diagram of the device is shown in the figure.

      The error injection device contains these basic parts:
      1.  Control circuitry and PIO interface
      2.  Memory
      3.  Sector counter
      4.  Delay counter
      5.  Duration counter
      6.  Error Injection circuitry

      The control circuit starts and stops the error injection,
interfaces to a personal computer, and controls the memory.  It is
also responsible for synchronizing the counters with the various
signals from the drive (index, sector clock, read gate, etc.) to
provide proper triggering.

      The memory section contains first-in, first-out (FIFO) memory
that is responsible for storing the error injecti...