WESTERN DIGITAL CORPORATION
===========================

   WD1003S-RAH

   +------------------------------------------------------------+
   +------------------------------------------------------------+

   Data bus: 16-bit, ISA

   Size: Half-length, full-height card

   Hard drives supported:  Two ST506/412 RLL drives

   Floppy drives supported: Two 360KB, 720KB, 1.2MB, or 1.44MB
   drives

<gopher://bitreich.org/I/th99/c/U-Z/20297-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |                    Function                     | Location |
   |-------------------------------------------------+----------|
   | 34-pin control cable connector-hard drives      |   CN1    |
   |-------------------------------------------------+----------|
   | 20-pin data cable connector-Drive 0             |   CN2    |
   |-------------------------------------------------+----------|
   | 20-pin data cable connector-Drive 1             |   CN3    |
   |-------------------------------------------------+----------|
   | 34-pin data cable connector-secondary hard      |   CN5    |
   | drive (See JP7 settings)                        |          |
   |-------------------------------------------------+----------|
   | 4-pin connector-drive active LED                |   CN6    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |              Function              | Location |  Setting   |
   |------------------------------------+----------+------------|
   |>> | Auto deselect enabled (PC/AT)  |   JP1    | pins 1 & 2 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |   | Auto deselect disabled         |   JP1    |    open    |
   |   | (Compaq)                       |          |            |
   |---+--------------------------------+----------+------------|
   |>> | Hard drive port address is     |   JP2    |    open    |
   |   | 1F0-1F7h & 3F0-3F7h            |          |            |
   |---+--------------------------------+----------+------------|
   |   | Hard drive port address is     |   JP2    |   closed   |
   |   | 170-177h & 370-377h            |          |            |
   |---+--------------------------------+----------+------------|
   |>> | Drive 0 translation disabled   |   JP4    | pins 1 & 2 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |   | Drive 0 translation enabled*   |   JP4    | pins 2 & 3 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |>> | Write Gate and drive select    |   JP5    | pins 2 & 3 |
   |   | lines are enabled only         |          |   closed   |
   |   |                                |          |            |
   |   | when drive is accessed         |          |            |
   |---+--------------------------------+----------+------------|
   |   | Write Gate and drive select    |   JP5    | pins 1 & 2 |
   |   | lines are disabled during      |          |   closed   |
   |   | power-up and when +5V is       |          |            |
   |   | <+4.15V                        |          |            |
   |---+--------------------------------+----------+------------|
   |>> | Drive 1 translation disabled   |   JP6    | pins 1 & 2 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |   | Drive 1 translation enabled*   |   JP6    | pins 2 & 3 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |>> | Input tied high                |   JP8    | pins 1 & 2 |
   |   |                                |          |   closed   |
   |---+--------------------------------+----------+------------|
   |   | Seek to LZ (663) on seek >     |   JP8    | pins 2 & 3 |
   |   | than 615. Step rate 0          |          |   closed   |
   |   |                                |          |            |
   |   | (11 m m                        |          |            |
   |------------------------------------------------------------|
   | Note: Translates 4 x 615 x 26 to 6 x 615 x 17              |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |               DRIVE ATTACHMENT CONFIGURATION               |
   |------------------------------------------------------------|
   |             Function              |          JP7           |
   |-----------------------------------+------------------------|
   | Both drives daisy-chained from    |                        |
   | CN1, or Drive 0  is  attached to  |                        |
   | CN1 and drive 1 is attached to    |  pins 1 & 2 and 2 & 3  |
   | CN5                               |  closed (vertically)   |
   |-----------------------------------+------------------------|
   | Drive 0 attached to CN5, Drive 1  |  pins 1 & 3 and 2 & 4  |
   | attached to  CN1                  | closed (horizontally)  |
   +------------------------------------------------------------+