Microsoft KB Archive/68986

= Change-Line Support and XT-Class Computers =

Article ID: 68986

Article Last Modified on 5/12/2003

-

APPLIES TO


 * Microsoft MS-DOS 3.1
 * Microsoft MS-DOS 3.2 Standard Edition
 * Microsoft MS-DOS 3.21 Standard Edition
 * Microsoft MS-DOS 3.3 Standard Edition
 * Microsoft MS-DOS 3.3a
 * Microsoft MS-DOS 4.0 Standard Edition
 * Microsoft MS-DOS 4.01 Standard Edition
 * Microsoft MS-DOS 5.0 Standard Edition
 * Microsoft MS-DOS 5.0a
 * Microsoft MS-DOS 6.0 Standard Edition
 * Microsoft MS-DOS 6.2 Standard Edition
 * Microsoft MS-DOS 6.21 Standard Edition
 * Microsoft MS-DOS 6.22 Standard Edition

-



This article was previously published under Q68986



SYMPTOMS
If you have a 3.5-inch floppy disk drive attached to an XT-class computer system, when you change disks and use the DIR command, you may see the directory from the previous disk.



CAUSE
This occurs because MS-DOS assumes that the 3.5-inch drive has change-line error detection. Most 3.5-inch drives provide change-line support; however, due to XT architecture, the change-line signal is not passed to MS-DOS.



WORKAROUND
Adding a DRIVPARM command to the CONFIG.SYS file may correct this problem. The following is sample DRIVPARM command to specify a 720-kilobyte 3.5-inch B drive:   DRIVPARM=/D:1 /F:2 Please note that the /C change-line support switch is omitted. When MS-DOS updates the drive parameters, it may remove the change-line support requirement.

The floppy disk drive manufacturer may be able to provide a device driver that corrects the change-line problem. A last option is to install a floppy drive controller and BIOS that fully support change-line error detection.

Additional query words: 6.22 3.3 3.30 3.3a 3.30a 4.0 4.00 4.01 5.00 5.00a 6.00 6.20

Keywords: KB68986

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.