Document Scope - Western Digital WD1007A-WAH User Manual

1.0

Document Scope

This document describes installation of the WDl007A-WAH/WA2 Winchester/Floppy
Disk Controller in the IBM * Personal Computer AT * . If you have an AT compatible,
you should refer to your system manuals or contact your dealer for information
concerning installation of the WDl007A-WAH/WA2. Refer to the following documents
for a more thorough explanation of board functions:
WDl007A-WAH/WA2 Data Sheet (79-000261)
WDl007A-WAH/WA2 Application Notes
WDl007A Support Diskette (Contact your local sales office)
2.0 Description
The WDl007A-WA2 and the WDl007A-WAH are single board Winchester Disk
Controllers designed to interface two ESDI compatible disk drives to the IBM PC/AT or
compatible host computer. The WDl007A-WA2 supports two 5.25 or 3.5 inch floppy
disk drives; the WDl007A-WAH is a hard disk only version of the controller.
The ESDI drives used with this controller generally have two modes of operation, soft
sector and hard sector. At this time the WDl007A-WA2 offers only the hard sector mode
of operation.
In most systems the BIOS and/or operating system supports only the older MFM/ST-506
drives which use 17 sectors per track. The ESDI disk drive typically has 34 sectors per
track when operating in the hard sector mode. To integrate the hard disk drive into the
AT environment, select a drive parameters table that reflects the physical characteristics
of the drive, i.e., the number of cylinders, heads, and sectors per track.
The WDl007A-WAH/WA2 controller has an optional BIOS ROM that provides drive
parameter tables, low-level formatting routines, and surface analysis routines. While
low-level formatting of the drive can be accomplished by several means, Western
Digital recommends that you use the low-level formatting routine present in the
WDl007A BIOS. If your controller does not have the BIOS option, obtain Western
Digital's WDFMT 2.10 formatting utility.
(*) IBM and AT are registered trademarks of International Business Machines Corporation.