WESTERN DIGITAL CORPORATION WD1002A-WX1 Replaced by the WD1004A-WX1 Data bus: 8-bit, PC/XT Size: Full-length, full-height card Hard drives supported: Two MFM ST506/412 drives Floppy drives supported: None Maximum heads/cyl.: 16 heads and 1024 cylinders [Image] 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 5-pin connector-DC power J4 USER CONFIGURABLE SETTINGS Function Location Setting » BIOS enabled W3 closed BIOS disabled W3 open » I/O port address 320h W4 pins 2 & 3 closed I/O port address 324h W4 pins 1 & 2 closed » BIOS ROM size 32K or 64K W5 pins 1 & 2 (hard-wired) closed BIOS ROM size 16K W5 pins 2 & 3 closed » 8 head hard drive with RWC W6 pins 2 & 3 supported closed 16 head hard drive supported W6 pins 1 & 2 (head select 3) closed » x Hard Drive Interrupt is IRQ5 W7 pins 1 & 2 (hard-wired) closed Hard Drive Interrupt is IRQ2 W7 pins 2 & 3 closed » Single controller setting, W8 pins 2 & 3 primary controller closed Dual controller setting, W8 pins 1 & 2 secondary controller closed » Not used S1/jumper 5 open » Not used S1/jumper 6 open » *Hard Drive Interrupt is IRQ5 S1/jumper 7 open *Hard Drive Interrupt is IRQ2 S1/jumper 7 closed *XT mode enabled S1/jumper 8 open *AT mode enabled S1/jumper 8 closed Note:* This controller can be purchased with several different BIOS revisions. These jumpers are not applicable when used with some BIOS revisions. BIOS REVISION "SUPER BIOS" DRIVE TYPE TABLE Drive Drive 0 1 # S1/1 S1/2 S1/3 S1/4 Cap. Hds Cyls. WP RWC 0 closed closed closed closed 21MB 4 612 450 450 1 open closed open closed 10MB 4 306 0 153 2 closed open closed open 10MB 2 615 450 450 3 open open open open 21MB 4 615 450 450 BIOS REVISION "G" DRIVE TYPE TABLE # Drive Drive 0 1 # S1/1 S1/2 S1/3 S1/4 Cap. Hds. Cyl. WP RWC 0 closed closed closed closed 20MB 4 612 none none 1 open closed open closed 10MB 2 612 128 128 2 closed open closed open 20MB 4 612 128 none 3 open open open open 10MB 4 306 0 none BIOS REVISION "H" DRIVE TYPE TABLE - S1 JUMPERS 3, 4, & 8 CONFIGURE DRIVE 0 JUMPERS 1, 2 & 7 CONFIGURE DRIVE 1 # S1/1 & S1/2 & S1/7 & Cap. Hds Cyl. WP RWC 3 4 8 0 closed closed closed 42MB 5 977 none none 1 open closed closed 31MB 5 733 300 none 2 closed open closed 33MB 6 640 none none 3 open open closed 62MB 8 1024 1024 1024 4 closed closed open 42MB 6 820 none none 5 open closed open 10MB 2 612 128 128 6 closed open open 20MB 4 612 128 none 7 open open open 10MB 4 306 0 none MISCELLANEOUS TECHNICAL NOTES The Super BIOS revision includes the following features not found in other revisions: ability to format bad tracks, dual controller operation, automatic configuration, virtual drive operation, and PC/AT compatibility. 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. Two additional jumpers may be present, W1 & W2, and are reserved for factory use and must not be changed.