
SOYO COMPUTER CO., LTD.

SY-020H


Processor               80486SX/80487SX/80486DX
Processor Speed         16/20/25/33/40/50(internal)/50/66(internal)MHz
Chip Set                SIS
Max. Onboard DRAM       32MB
Cache                   32/64/128/256KB
BIOS                    AMI
Dimensions              245mm x 220mm
I/O Options             None
NPU Options             4167


[Image]

                                CONNECTIONS

  Purpose                  Location    Purpose                  Location

  Power LED & keylock        J17       External battery           J20

  Speaker                    J18       Turbo switch               J21

  Reset switch               J19       Turbo LED                  J22

  Note:The oscillator at OSC1 must match the external speed of the CPU
  installed.

                        USER CONFIGURABLE SETTINGS

                 Function                     Jumper          Position

     Monitor type select monochrome            JP3             Open

      Monitor type select color                 JP3            Closed

     CMOS memory normal operation              JP5          pins 1 & 2
                                                               closed

      CMOS memory clear                         JP5          pins 2 & 3
                                                               closed

     Power good signal detect from             JP7          pins 1 & 2
      board                                                    closed

      Power good signal detect from             JP7          pins 2 & 3
      power supply                                             closed

     Keyboard BIOS clock source select        JP18          pins 1 & 2
      programmable timer                                       closed

      Keyboard BIOS clock source select        JP18          pins 2 & 3
      7MHz                                                     closed

     CPU speed select  to 25MHz              JP19          pins 1 & 2
                                                               closed

      CPU speed select < 25MHz                 JP19          pins 2 & 3
                                                               closed

              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

      8MB         (4) 1M x 9      (4) 1M x 9

      16MB        (4) 4M x 9         NONE

      20MB        (4) 1M x 9      (4) 4M x 9

      32MB        (4) 4M x 9      (4) 4M x 9

                    CACHE CONFIGURATION

     Size          Bank 0         Bank 1          TAG

     32KB        (4) 8K x 8        NONE       (2) 4K x 4

     64KB        (4) 8K x 8     (4) 8K x 8    (2) 4K x 4

     128KB      (4) 32K x 8        NONE       (2) 16K x 4

     256KB      (4) 32K x 8    (4) 32K x 8    (2) 16K x 4

                        CACHE JUMPER CONFIGURATION

  Size     JP8   JP9    JP10   JP11    JP12   JP13    JP14   JP15   JP16

  32KB     1 &   1 &    1 &     1 &    1 &     1 &    1 &     1 &   1 & 2
           2      2      2      2       2      2       2      2

  64KB     2 &   1 &    1 &     2 &    1 &     1 &    2 &     2 &   1 & 2
           3      2      2      3       2      2       3      3

  128KB    2 &   2 &    1 &     2 &    2 &     1 &    1 &     1 &   2 & 3
           3      3      2      3       3      2       2      2

  256KB    2 &   2 &    2 &     2 &    2 &     2 &    2 &     2 &   2 & 3
           3      3      3      3       3      3       3      3

  Note: Pins designated should be in the closed position.

                             CPU CONFIGURATION

       Type               JP24              JP25              JP26

      80486SX          pins 2 & 3           Open              Open
                         closed

      80487SX          pins 1 & 2          Closed           pins 2 & 3
                         closed                              closed

      80486DX          pins 1 & 2          Closed           pins 1 & 2
                         closed                              closed

