YOUNG MICRO SYSTEMS, INC.
=========================

   VS486F/S-3VL

   Processor         80486SX/80486DX/80486DX2                     
   Processor Speed   25/33/40/50(internal)/66(internal)MHz        
   Chip Set          Symphony                                     
   Max. Onboard DRAM 64MB                                         
   Cache             64/256/1024KB                                
   BIOS              AMI                                          
   Dimensions        230mm x 218mm                                
   I/O Options       32-bit VESA local bus slots (3)              
   NPU Options       None                                         

<gopher://bitreich.org/I/th99/m/U-Z/31707-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   | Purpose           | Location | Purpose          | Location |
   |-------------------+----------+------------------+----------|
   | External battery  |    J1    | Turbo switch     |   JP24   |
   |-------------------+----------+------------------+----------|
   | Power LED &       |   JP20   | 32-bit VESA      |    S1    |
   | keylock           |          | Local bus slot   |          |
   |-------------------+----------+------------------+----------|
   | Speaker           |   JP21   | 32-bit VESA      |    S2    |
   |                   |          | Local bus slot   |          |
   |-------------------+----------+------------------+----------|
   | Reset switch      |   JP22   | 32-bit VESA      |    S3    |
   |                   |          | Local bus slot   |          |
   |-------------------+----------+------------------+----------|
   | Turbo LED         |   JP23   |                  |          |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |               Function               | Jumper |  Position  |
   |--------------------------------------+--------+------------|
   |>> | Factory configured - do not      |   J2   |  Unknown   |
   |   | alter                            |        |            |
   |---+----------------------------------+--------+------------|
   |>> | Flash BIOS write protect enabled |  JP2   | pins 1 & 2 |
   |   |                                  |        |   closed   |
   |---+----------------------------------+--------+------------|
   |   | Flash BIOS write protect         |  JP2   | pins 2 & 3 |
   |   | disabled                         |        |   closed   |
   |---+----------------------------------+--------+------------|
   |>> | Factory configured - do not      |  JP3   |  Unknown   |
   |   | alter                            |        |            |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DRAM CONFIGURATION                     |
   |------------------------------------------------------------|
   |       Size       |       Bank 0       |       Bank 1       |
   |------------------+--------------------+--------------------|
   |       1MB        |    (4) 256K x 9    |        NONE        |
   |------------------+--------------------+--------------------|
   |       2MB        |    (4) 256K x 9    |    (4) 256K x 9    |
   |------------------+--------------------+--------------------|
   |       4MB        |     (4) 1M x 9     |        NONE        |
   |------------------+--------------------+--------------------|
   |       5MB        |     (4) 1M x 9     |    (4) 256K x 9    |
   |------------------+--------------------+--------------------|
   |       8MB        |     (4) 1M x 9     |     (4) 1M x 9     |
   |------------------+--------------------+--------------------|
   |       16MB       |     (4) 4M x 9     |        NONE        |
   |------------------+--------------------+--------------------|
   |       17MB       |     (4) 4M x 9     |    (4) 256K x 9    |
   |------------------+--------------------+--------------------|
   |       20MB       |     (4) 1M x 9     |     (4) 4M x 9     |
   |------------------+--------------------+--------------------|
   |       32MB       |     (4) 4M x 9     |     (4) 4M x 9     |
   |------------------+--------------------+--------------------|
   |       64MB       |    (4) 16M x 9     |        NONE        |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                  CPU SPEED CONFIGURATION                   |
   |------------------------------------------------------------|
   |Speed |  JA1   |  JP4  | JP5  | JP6  | JP7  | JP10  | JP11  |
   |------+--------+-------+------+------+------+-------+-------|
   |25MHz |pins 2 &|pins 2 | Open |Closed|Closed|pins 1 |pins 2 |
   |      |   3    |  & 3  |      |      |      |  & 2  |  & 3  |
   |------+--------+-------+------+------+------+-------+-------|
   |33MHz |pins 2 &|pins 2 |Closed| Open |Closed|pins 1 |pins 2 |
   |      |   3    |  & 3  |      |      |      |  & 2  |  & 3  |
   |------+--------+-------+------+------+------+-------+-------|
   | 50I  |pins 1 &|pins 1 | Open |Closed|Closed|pins 1 |pins 1 |
   | MHz  |   2    |  & 2  |      |      |      |  & 2  |  & 2  |
   |------+--------+-------+------+------+------+-------+-------|
   | 66I  |pins 2 &|pins 2 |Closed| Open |Closed|pins 1 |pins 2 |
   | MHz  |   3    |  & 3  |      |      |      |  & 2  |  & 3  |
   |------------------------------------------------------------|
   |Note:Pins designated should be in the closed position.      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                  CPU SPEED CONFIGURATION                   |
   |------------------------------------------------------------|
   | Speed | JP12  | JP13 | JP14 |JP15| JP16 | JP17 | JP18 |JP30|
   |-------+-------+------+------+----+------+------+------+----|
   | 25MHz |Closed | Open |Closed|Open| Open |Closed| Open |Open|
   |-------+-------+------+------+----+------+------+------+----|
   | 33MHz |Closed | Open |Closed|Open| Open |Closed| Open |Open|
   |-------+-------+------+------+----+------+------+------+----|
   |50I MHz|Closed |Closed| Open |Open|Closed|Closed|Closed|Open|
   |-------+-------+------+------+----+------+------+------+----|
   |66I MHz|Closed |Closed| Open |Open|Closed|Closed|Closed|Open|
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    CACHE CONFIGURATION                     |
   |------------------------------------------------------------|
   |    Size    | Max Cachable  |     Cache     |      TAG      |
   |------------+---------------+---------------+---------------|
   |    64KB    |      8MB      |  (4) 8K x 8   |  (1) 8K x 8   |
   |------------+---------------+---------------+---------------|
   |   128KB    |     32MB      |  (4) 32K x 8  |  (1) 32K x 8  |
   |------------+---------------+---------------+---------------|
   |   256KB    |     64MB      | (4) 128K x 8  | (1) 128K x 8  |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 CACHE JUMPER CONFIGURATION                 |
   |------------------------------------------------------------|
   | Size  |    JP8     |   JP9    |   JP19   |  JP25  |  JP26  |
   |-------+------------+----------+----------+--------+--------|
   | 64KB  | pins 2 & 3 | pins 1 & | pins 1 & | pins 1 | pins 1 |
   |       |            |    2     |    2     |  & 2   |  & 2   |
   |-------+------------+----------+----------+--------+--------|
   | 256KB | pins 2 & 3 | pins 1 & | pins 2 & | pins 2 | pins 2 |
   |       |            |    2     |    3     |  & 3   |  & 3   |
   |-------+------------+----------+----------+--------+--------|
   |  1MB  | pins 1 & 2 | pins 2 & | pins 2 & | pins 2 | pins 2 |
   |       |            |    3     |    3     |  & 3   |  & 3   |
   +------------------------------------------------------------+