Browse Prior Art Database

Write Retry Function on Low-End Disk System

IP.com Disclosure Number: IPCOM000035757D
Original Publication Date: 1989-Aug-01
Included in the Prior Art Database: 2005-Jan-28
Document File: 2 page(s) / 68K

Publishing Venue

IBM

Related People

Kibashi, A: AUTHOR [+2]

Abstract

This article describes a technique for a hard disk drive to retry write operation without any host system operation.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Write Retry Function on Low-End Disk System

This article describes a technique for a hard disk drive to retry write operation without any host system operation.

A disk drive system which has a sector servo head positioning mechanism can only detect head positioning error after some calculation time by microcode or other external hardware. Usually this detection is done when a hard disk controller starts writing data into disk (Fig. 1). This technique adds an input pin to a hard disk controller and re-writes the data when a head positioning error is detected.

When the head positioning error is detected, a microprocessor or other servo hardware provides a signal to the input pin of the hard disk controller. At this time, the hard disk controller is writing data and getting data from a host computer system, so, after this, the hard disk controller stops the writing operation immediately and data transferring to the host system pauses. After this operation, the data to be written into the target sector is stored in a buffer of the hard disk controller. Thus, the microprocessor can issue a write command to the hard disk controller for the same sector after a head is positioned correctly.

Fig. 2 shows the operational steps of the 'Microcode', 'Hard Disk Controller' and 'Host System' according to this technique in the case of 5 sector's data being written into disk.

(Image Omitted)

1

Page 2 of 2

2

[This page contains 5 pictures or other non-text objects]