WESTERN DIGITAL CORPORATION

WD286-WDM20

Processor               80286
Processor Speed         12.5MHz
Chip Set                Faraday
Max. Onboard DRAM       4MB
Cache                   None
BIOS                    AMI
Dimensions              330mm x 218mm
I/O Options             Parallel port, serial ports (2), bus mouse port,
                        floppy drive interface, ST506/412 interface, video
                        interface, IDE interface
NPU Options             80287

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                 Location

  IDE interface                J5       Floppy drive               J16
  (optional)                            interface

  Hard drive access LED       J10       ST506/412 drive            J17
                                        control

  Reset switch                J11       Serial port 1              J19

  ST506/412 data (Drive       J12       Serial port 2              J20
  0)

  ST506/412 data (Drive       J13       Video interface            J21
  1)

  Power LED & keylock         J14       PS/2 mouse port            J22

  Parallel port (LPT1)        J15       Speaker                    J24

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

  »   Factory configured - do not alter      W4 & W6           Open

  »   Factory configured - do not alter        W7             Closed

  »   Floppy drive interrupt enabled           W8             Closed
      (IRQ6)

      Floppy drive interrupt disabled          W8              Open
      (IRQ6)

  »   Keyboard select AT compatible            W12             Open
      (101 key)

      Keyboard select XT compatible (83        W12            Closed
      key)

  »   Video port interrupt enabled             W13            Closed
      (IRQ9)

      Video port interrupt disabled            W13             Open
      (IRQ9)

  »   Mouse port interrupt enabled             W17            Closed
      (IRQ12)

      Mouse port interrupt disabled            W17             Open
      (IRQ12)

  »   Parallel port interrupt enabled          W19            Closed
      (IRQ7)

      Parallel port interrupt disabled         W19             Open
      (IRQ7)

  »   Serial port 2 interrupt enabled          W20            Closed
      (IRQ3)

      Serial port 2 interrupt disabled         W20             Open
      (IRQ3)

  »   Serial port 1 interrupt enabled          W21            Closed
      (IRQ4)

      Serial port 1 interrupt disabled         W21             Open
      (IRQ4)

  »   Video port NMI enabled                   W23            Closed

      Video port NMI disabled                  W23             Open

  »   Video port data buffering enabled        W24           pins 1 & 2
                                                              closed

      Video port data buffering                W24           pins 2 & 3
      disabled                                                closed

  »   Video port enabled                       W25            Closed

      Video port disabled                      W25             Open

              DRAM CONFIGURATION

      Size          Bank 0          Bank 1

      1MB         (2) 256K x 9   (2) 256K x 9

      2MB         (2) 1M x 9         NONE

      4MB         (2) 1M x 9      (2) 1M x 9

      8MB         (2) 4M x 9         NONE

      10MB        (2) 1M x 9      (2) 4M x 9

      16MB        (2) 4M x 9      (2) 4M x 9

                            VIDEO CONFIGURATION

       Type         S1/1      S1/2     S1/3     S1/4      S1/5      W18

    Monochrome       Off      Off       On       Off      Off      1 & 2

  CGA-40 columns     On       Off       Off      On       Off      2 & 3

  CGA-80 columns     Off      Off       Off      On       Off      2 & 3

  EGA-200 lines      On        On       On       Off      Off      2 & 3

    EGA-350/480      Off       On       On       Off      Off      2 & 3
      lines

  Note: Pins designated should be in the closed position.

                         HARD DRIVE CONFIGURATION

      Type             W3            W5            W10           W22

    ST506/412        Closed        Closed         Open           Open

       IDE            Open          Open         Closed         Closed

  Expansion card      Open          Open          Open           Open

  Note:An expansion card hard drive controller may be used in addition to
  the ST506/412 with the ST506/412 Settings.