MICRONICS COMPUTERS, INC.

MINI 486 SYSTEM BOARD

Processor        80486SX/80486DX/ODP486SX/80486DX2
Processor Speed  25/33/50(internal)/50/66(internal)MHz
Chip Set         Micronics
Max. Onboard DRAM64MB
Cache            64/128/256KB
BIOS             Phoenix
Dimensions       230mm x 218mm
I/O Options      None
NPU Options      None

[Image]

                                CONNECTIONS

  Purpose                   Location    Purpose                 Location

  External keyboard            J1       Turbo switch              W16
  connector

  Speaker                     J20       Turbo LED                 W17

  Reset switch                W15       Power LED & keylock       W18

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

  »   Monitor type select color                W2             Closed

      Monitor type select monochrome           W2              Open

  »   Real Time Clock enabled                  W3           pins 1 & 2
                                                              closed

      External battery enabled                 W3           pins 2 & 3
                                                              closed

  »   Factory configured - do not             W43           pins 1 & 2
      alter                                                   closed

                            DRAM CONFIGURATION

     Size         Bank 0          Bank 1         Bank 2         Bank 3

     1MB         (1) 256K x        NONE           NONE           NONE
                    36

     2MB         (1) 256K x     (1) 256K x        NONE           NONE
                    36              36

     4MB        (1) 1M x 36        NONE           NONE           NONE

     6MB         (1) 256K x     (1) 256K x     (1) 1M x 36       NONE
                    36              36

     8MB        (1) 1M x 36    (1) 1M x 36        NONE           NONE

     10MB        (1) 256K x     (1) 256K x     (1) 1M x 36   (1) 1M x 36
                    36              36

     12MB       (1) 1M x 36    (1) 1M x 36     (1) 1M x 36       NONE

     16MB       (1) 1M x 36    (1) 1M x 36     (1) 1M x 36   (1) 1M x 36

     16MB       (1) 4M x 36        NONE           NONE           NONE

     18MB        (1) 256K x     (1) 256K x     (1) 4M x 36       NONE
                    36              36

     20MB       (1) 1M x 36    (1) 4M x 36        NONE           NONE

     24MB       (1) 1M x 36    (1) 1M x 36     (1) 4M x 36       NONE

     32MB       (1) 4M x 36    (1) 4M x 36        NONE           NONE

     36MB       (1) 1M x 36    (1) 4M x 36     (1) 4M x 36       NONE

     40MB       (1) 1M x 36    (1) 1M x 36     (1) 4M x 36   (1) 4M x 36

     48MB       (1) 4M x 36     (1) 4M x 9     (1) 4M x 36       NONE

     64MB       (1) 4M x 36     (1) 4M x 9     (1) 4M x 36   (1) 4M x 36

                            CACHE CONFIGURATION

     Size         Bank 0      Bank 1        TAG/U41           TAG/U42

     64KB         (4) 8K x    (4) 8K x     (1) 8K x 8           N/A
                     8           8

     128KB       (4) 32K x     NONE       (1) 32K x 8           N/A
                     8

     256KB       (4) 32K x   (4) 32K x    (1) 32K x 8           N/A
                     8           8

  Note:Tag/U42 is not currently in use.

                        CACHE JUMPER CONFIGURATION

   Size     W5     W6    W7     W8     W9    W10     W11    W12      W13

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

  128KB     2 &    2 &   1 &    2 &    2 &    1 &    2 &     1 &    1 & 2
             3     3      2     3      3      2       3      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 TYPE CONFIGURATION

        Type                 W14                  W19

       80486SX               N/A           pins 1 & 2 closed

       80486DX         pins 2 & 3 closed   pins 2 & 3 closed

      ODP486SX         pins 1 & 2 closed   pins 2 & 3 closed

      80486DX2         pins 2 & 3 closed   pins 2 & 3 closed

                   CPU SPEED CONFIGURATION

        Speed                W21                  W22

        25MHz          pins 2 & 3 closed   pins 2 & 3 closed

        33MHz          pins 1 & 2 closed   pins 2 & 3 closed

       50i MHz         pins 2 & 3 closed   pins 2 & 3 closed

        50MHz          pins 1 & 2 closed   pins 1 & 2 closed

       66i MHz         pins 1 & 2 closed   pins 2 & 3 closed