WESTERN DIGITAL CORPORATION

WD1002-27X

Replaced by the WD1004-27X

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

[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 DC power connector                         J4

                         DRIVE TYPE CONFIGURATION

               DRIVE 1           DRIVE 0

  Type #     S1/jumper 1       S1/jumper 2     S1/jumper 3   S1/jumper 4

    0           closed           closed          closed         closed

    1            open            closed           open          closed

    2           closed            open           closed          open

    3            open             open            open           open

                        USER CONFIGURABLE SETTINGS

               Function                    Location           Setting

  »   BIOS enabled                            W3               closed

      BIOS disabled                           W3                open

  »   I/O port address is 324-327h            W4             pins 1 & 2
                                                               closed

      I/O port address is 320-323h            W4             pins 2 & 3
                                                               closed

  »   2732 & 2764 BIOS supported              W5             pins 1 & 2
      (hard-wired)                                             closed

      2716 BIOS supported                     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
                                                               closed

  »   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

  »   Firmware translation enabled            W9               closed

      Firmware translation disabled           W9                open

  »   Hard Drive Interrupt is IRQ5        S1/jumper 7           open

      Hard Drive Interrupt is IRQ2        S1/jumper 7          closed

  »   AT mode enabled                     S1/jumper 8          closed

      XT mode enabled                     S1/jumper 8           open

                           BIOS DRIVE TYPE TABLE

  Type #         Formatted        Heads      Physical/Logical Cylinders
                 Capacity

     0             65MB             5                 981/1023

     1             92MB             7                 987/1023

     2             33MB             4                  612/935

     3             33MB             4                  615/940

                    TRANSLATION CONFIGURATION - S1 & W9

  SPT      BIOS         Dynamic        RLL      S1        S1        W9
                                      BIOS
         Translate   Configuration             Jumper   Jumper      see
                                      Type       5        6        above

   -     Undefined         -            -      open      open        -

  17       yes            no            1      closed    open      open

  26        no            yes           2      open     closed     open

  17        no            yes           0      closed   closed    closed

                       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.