TYAN COMPUTER CORPORATION
=========================

   486VL EISA VESA LOCAL BUS (REV. 1.0)

   Processor         80486SX/80487SX/80486DX/80486DX2             
   Processor Speed   20/25/33/50 (Internal)/50/66 (Internal)MHz   
   Chip Set          SIS                                          
   Max. Onboard DRAM 256MB                                        
   Cache             64/128/256/512/1024KB                        
   BIOS              AMI                                          
   Dimensions        330mm x 220mm                                
   I/O Options       32-bit VESA local bus slots (2)              
   NPU Options       None                                         

<gopher://bitreich.org/I/th99/m/S-T/31674-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose      | Location | Purpose               | Location |
   |--------------+----------+-----------------------+----------|
   | Power LED &  |   JP20   | Turbo switch          |   JP23   |
   | keylock      |          |                       |          |
   |--------------+----------+-----------------------+----------|
   | Speaker      |   JP21   | Turbo LED             |   JP24   |
   |--------------+----------+-----------------------+----------|
   | Reset switch |   JP22   | 32-bit VESA Local bus | S1 & S2  |
   |              |          | slots                 |          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |            Function             | Jumper/Switch | Position |
   |---------------------------------+---------------+----------|
   |>> | Factory configured - do not |     JP18      |   Open   |
   |   | alter                       |               |          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DRAM CONFIGURATION                     |
   |------------------------------------------------------------|
   | Size  |   Bank 0    |   Bank 1   |   Bank 2   |   Bank 3   |
   |-------+-------------+------------+------------+------------|
   |  4MB  | (4) 1M x 9  |    NONE    |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   |  8MB  | (4) 1M x 9  | (4) 1M x 9 |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 12MB  | (4) 1M x 9  | (4) 1M x 9 | (4) 1M x 9 |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 16MB  | (4) 1M x 9  | (4) 1M x 9 | (4) 1M x 9 | (4) 1M x 9 |
   |-------+-------------+------------+------------+------------|
   | 16MB  | (4) 4M x 9  |    NONE    |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 20MB  | (4) 1M x 9  | (4) 4M x 9 |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 24MB  | (4) 1M x 9  | (4) 1M x 9 | (4) 4M x 9 |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 28MB  | (4) 1M x 9  | (4) 1M x 9 | (4) 1M x 9 | (4) 4M x 9 |
   |-------+-------------+------------+------------+------------|
   | 32MB  | (4) 4M x 9  | (4) 4M x 9 |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 36MB  | (4) 1M x 9  | (4) 4M x 9 | (4) 4M x 9 |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 40MB  | (4) 1M x 9  | (4) 1M x 9 | (4) 4M x 9 | (4) 4M x 9 |
   |-------+-------------+------------+------------+------------|
   | 48MB  | (4) 4M x 9  | (4) 4M x 9 | (4) 4M x 9 |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 52MB  | (4) 1M x 9  | (4) 4M x 9 | (4) 4M x 9 | (4) 4M x 9 |
   |-------+-------------+------------+------------+------------|
   | 64MB  | (4) 4M x 9  | (4) 4M x 9 | (4) 4M x 9 | (4) 4M x 9 |
   |-------+-------------+------------+------------+------------|
   | 64MB  | (4) 16M x 9 |    NONE    |    NONE    |    NONE    |
   |-------+-------------+------------+------------+------------|
   | 128MB | (4) 16M x 9 | (4) 16M x  |    NONE    |    NONE    |
   |       |             |     9      |            |            |
   |-------+-------------+------------+------------+------------|
   | 192MB | (4) 16M x 9 | (4) 16M x  | (4) 16M x  |    NONE    |
   |       |             |     9      |     9      |            |
   |-------+-------------+------------+------------+------------|
   | 256MB | (4) 16M x 9 | (4) 16M x  | (4) 16M x  | (4) 16M x  |
   |       |             |     9      |     9      |     9      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    CACHE CONFIGURATION                     |
   |------------------------------------------------------------|
   |  Size  |   Bank 0    |   Bank 1   | TAG (U15)  | TAG (U16) |
   |--------+-------------+------------+------------+-----------|
   |  64KB  | (4) 8K x 8  | (4) 8K x 8 | (1) 8K x 8 |   NONE    |
   |--------+-------------+------------+------------+-----------|
   | 128KB  | (4) 32K x 8 |   Bank 0   | (1) 8K x 8 |   NONE    |
   |--------+-------------+------------+------------+-----------|
   | 256KB  | (4) 32K x 8 | (4) 32K x  | (1) 8K x 8 |   NONE    |
   |        |             |     8      |            |           |
   |--------+-------------+------------+------------+-----------|
   | 512KB  | (8) 32K x 8 | (8) 32K x  | (1) 32K x  |   NONE    |
   |        |             |     8      |     8      |           |
   |--------+-------------+------------+------------+-----------|
   | 1024KB | (8) 128K x  |    NONE    | (1) 32K x  | (1) 32K x |
   |        |      8      |            |     8      |     8     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 CACHE JUMPER CONFIGURATION                 |
   |------------------------------------------------------------|
   | Size | JP5  | JP6  | JP7  |JP8 |JP9 |JP10 |JP12 |JP13 |JP14|
   |------+------+------+------+----+----+-----+-----+-----+----|
   | 64KB | Open | Open | Open |2 & |1 & |1 & 2|Open |2 & 3|1 & |
   |      |      |      |      | 3  | 2  |     |     |     | 2  |
   |------+------+------+------+----+----+-----+-----+-----+----|
   |128KB |Closed| Open | Open |2 & |1 & |1 & 2|Open |1 & 2|1 & |
   |      |      |      |      | 3  | 2  |     |     |     | 2  |
   |------+------+------+------+----+----+-----+-----+-----+----|
   |256KB |Closed|Closed| Open |2 & |2 & |1 & 2|Open |2 & 3|2 & |
   |      |      |      |      | 3  | 3  |     |     |     | 3  |
   |------+------+------+------+----+----+-----+-----+-----+----|
   |512KB |Closed|Closed|Closed|2 & |1 & |1 & 2|1 & 2|1 & 2|1 & |
   |      |      |      |      | 3  | 2  |     |     |     | 2  |
   |------+------+------+------+----+----+-----+-----+-----+----|
   |1024KB|Closed|Closed|Closed|1 & |1 & |2 & 3|2 & 3|2 & 3|2 & |
   |      |      |      |      | 2  | 2  |     |     |     | 3  |
   |------------------------------------------------------------|
   |Note:Pins designated should be in the closed position.      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   CPU TYPE CONFIGURATION                   |
   |------------------------------------------------------------|
   |    Type    |        JP1         |           JP2            |
   |------------+--------------------+--------------------------|
   |  80486SX   | Pins 1 & 2 closed  |    pins 2 & 3 closed     |
   |------------+--------------------+--------------------------|
   |  80487SX   | Pins 1 & 2 closed  |    pins 2 & 3 closed     |
   |------------+--------------------+--------------------------|
   |  80486DX   | Pins 2 & 3 closed  | pins 1 & 2, 3 & 4 closed |
   |------------+--------------------+--------------------------|
   |  80486DX2  | Pins 2 & 3 closed  | pins 1 & 2, 3 & 4 closed |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                  CPU SPEED CONFIGURATION                   |
   |------------------------------------------------------------|
   |           Speed            |             JP16              |
   |----------------------------+-------------------------------|
   |          GBP 33MHz           |       pins 2 & 3 closed       |
   |----------------------------+-------------------------------|
   |          > 33MHz           |       pins 1 & 2 closed       |
   +------------------------------------------------------------+