COMPAQ COMPUTER CORPORATION
===========================

   000519 HARD DISK DRIVE CONTROLLER BOARD

   +------------------------------------------------------------+
   |------------------------------------------------------------|
   | Data bus:         | 16-bit, ISA                            |
   |-------------------+----------------------------------------|
   | Size:             | Three/quarter-length, full-height card |
   |-------------------+----------------------------------------|
   | Hard drive        | Two IDE (AT) Interface drives          |
   | supported:        |                                        |
   |-------------------+----------------------------------------|
   | Floppy drives     | Two 360KB, 720KB, 1.2MB, or 1.44MB     |
   | supported:        | drives                                 |
   +------------------------------------------------------------+

<gopher://bitreich.org/I/th99/c/C-D/20371-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |                   Function                    |  Location  |
   |-----------------------------------------------+------------|
   | 40-pin IDE(AT) Interface connector            |    CN1     |
   |-----------------------------------------------+------------|
   | 34-pin control cable connector - floppy drive |    CN2     |
   |-----------------------------------------------+------------|
   | 10-pin serial port (COM1/2) - external        |    CN3     |
   |-----------------------------------------------+------------|
   | 25-pin parallel port (LPT1/2) - external      |    CN4     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |             Function              |   Location   | Setting |
   |-----------------------------------+--------------+---------|
   |>> | Hard drive port address is    | SW500/switch |  open   |
   |   | 1F0-1F7h                      |      1       |         |
   |   |                               |              |         |
   |   | Floppy drive port address is  |              |         |
   |   | 3F0-3F7h                      |              |         |
   |---+-------------------------------+--------------+---------|
   |   | Hard drive port address is    | SW500/switch | closed  |
   |   | 170-177h                      |      1       |         |
   |   |                               |              |         |
   |   | Floppy drive port address is  |              |         |
   |   | 370-377h                      |              |         |
   |---+-------------------------------+--------------+---------|
   |>> | High-speed floppy drive       | SW500/switch | closed  |
   |   | transfer rate enabled         |      2       |         |
   |---+-------------------------------+--------------+---------|
   |   | High-speed floppy drive       | SW500/switch |  open   |
   |   | transfer rate disabled        |      2       |         |
   |---+-------------------------------+--------------+---------|
   |>> | Hard drive enabled            | SW500/switch |  open   |
   |   |                               |      3       |         |
   |---+-------------------------------+--------------+---------|
   |   | Hard drive disabled           | SW500/switch | closed  |
   |   |                               |      3       |         |
   |---+-------------------------------+--------------+---------|
   |>> | Serial Port (CN3) is set to   | SW500/switch |  open   |
   |   | COM1                          |      4       |         |
   |---+-------------------------------+--------------+---------|
   |   | Serial Port (CN3) is set to   | SW500/switch | closed  |
   |   | COM2                          |      4       |         |
   |---+-------------------------------+--------------+---------|
   |>> | Serial Port (CN3) enabled     | SW500/switch |  open   |
   |   |                               |      5       |         |
   |---+-------------------------------+--------------+---------|
   |   | Serial Port (CN3) disabled    | SW500/switch | closed  |
   |   |                               |      5       |         |
   |---+-------------------------------+--------------+---------|
   |>> | Parallel Port (CN3) enabled   | SW500/switch |  open   |
   |   |                               |      6       |         |
   |---+-------------------------------+--------------+---------|
   |   | Parallel Port (CN3) disabled  | SW500/switch | closed  |
   |   |                               |      6       |         |
   +------------------------------------------------------------+