WESTERN DIGITAL CORPORATION

WD1002A-27X

Replaced by the WD1004A-27X

Data bus: 8-bit, PC/XT

Size: Half-length, full-height card

Hard drives supported: Two RLL ST506/412 drives

Floppy drives supported: None

Maximum heads/cyl.: 16 heads and 1024 cylinders

CONNECTIONS

Function

Location

34-pin control cable connector-hard drive

J1

20-pin data cable connector-drive 0

J2

20-pin data cable connector-drive 1

J3

USER CONFIGURABLE SETTINGS

Mode

Mode Description

Jumper

Position

 

»

»

1

Supports low-level and dynamic low-level formatting. Performs logical translations; (i.e.-4 hds., 615 cyls. and 26 SPT would be seen by DOS as 4 hds. 940 cyls. 17 SPT. Supports only up to 16 heads and 663 cylinders (physical).

 

W1

W2

 

closed

closed

 

 

2

Supports low-level and dynamic low-level formatting. Does not do logical translation. Supports up to 16 heads and 1024 cylinders (physical).

W1

W2

open

open

MISCELLANEOUS TECHNICAL NOTES

This controller has a built-in low-level format program. To enter the program run the DEBUG utility supplied with DOS and at the prompt enter: G=C800:5.