PC CALC, INC.
=============

   AT-TURBO 286 1800

   Processor             80286                                    
   Processor Speed       15MHz                                    
   Chip Set              None                                     
   Max. Onboard DRAM     1MB                                      
   Cache                 None                                     
   BIOS                  Phoenix                                  
   Dimensions            355mm x 304mm                            
   I/O Options           None                                     
   NPU Options           80287                                    

<gopher://bitreich.org/I/th99/m/P-R/30153-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose             | Location | Purpose        | Location |
   |---------------------+----------+----------------+----------|
   | Speaker             |   J19    | Turbo switch   |   J25    |
   |---------------------+----------+----------------+----------|
   | Power LED & keylock |   J20    | Turbo LED      |   J27    |
   |---------------------+----------+----------------+----------|
   | Reset switch        |   J24    |                |          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |             Function              | Jumper |   Position    |
   |-----------------------------------+--------+---------------|
   |>> | DRAM select 1 wait state      |   E1   |     Open      |
   |---+-------------------------------+--------+---------------|
   |   | DRAM select 0 wait states     |   E1   |    Closed     |
   |---+-------------------------------+--------+---------------|
   |>> | NPU speed select high         |  J29   |  pins 1 & 2   |
   |   |                               |        |    closed     |
   |---+-------------------------------+--------+---------------|
   |   | NPU speed select low          |  J29   |  pins 2 & 3   |
   |   |                               |        |    closed     |
   |---+-------------------------------+--------+---------------|
   |>> | Monitor type select color     |  SW1   |    Closed     |
   |---+-------------------------------+--------+---------------|
   |   | Monitor type select           |  SW1   |     Open      |
   |   | monochrome                    |        |               |
   |---+-------------------------------+--------+---------------|
   |>> | BIOS type select 27128        |  U57   | pins 1 & 8, 2 |
   |   |                               |        |  & 7 closed   |
   |---+-------------------------------+--------+---------------|
   |   | BIOS type select 27256        |  U57   | pins 3 & 6, 4 |
   |   |                               |        |  & 5 closed   |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DRAM CONFIGURATION                     |
   |------------------------------------------------------------|
   |       Size       |       Bank 0       |       Bank 1       |
   |------------------+--------------------+--------------------|
   |      512KB       |     (18) 41256     |        NONE        |
   |------------------+--------------------+--------------------|
   |      640KB       |     (18) 41256     |     (18) 4164      |
   |------------------+--------------------+--------------------|
   |       1MB        |     (18) 41256     |     (18) 41256     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 DRAM JUMPER CONFIGURATION                  |
   |------------------------------------------------------------|
   |         Size         |       J17        |       J18        |
   |----------------------+------------------+------------------|
   |        512KB         |    pins 2 & 3    |    pins 2 & 3    |
   |                      |      closed      |      closed      |
   |----------------------+------------------+------------------|
   |        640KB         |    pins 2 & 3    |    pins 1 & 2    |
   |                      |      closed      |      closed      |
   |----------------------+------------------+------------------|
   |      1MB (640KB      |    pins 1 & 2    |    pins 1 & 2    |
   | base/384KB extended) |      closed      |      closed      |
   |----------------------+------------------+------------------|
   |      1MB (512KB      |    pins 1 & 2    |    pins 2 & 3    |
   | base/512KB extended) |      closed      |      closed      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |               EXTERNAL BATTERY CONFIGURATION               |
   |------------------------------------------------------------|
   |        Size        |        J22        |        J31        |
   |--------------------+-------------------+-------------------|
   |      Lithium       |      Closed       |       Open        |
   |--------------------+-------------------+-------------------|
   |    Rechargeable    |      Closed       |      Closed       |
   +------------------------------------------------------------+