
MICRO EXPRESS, INC.

FOREX 486 VESA (Rev. VL 421A/422)

Processor         80486SX/80487SX/80486DX/ODP486SX/80486DX2
Processor Speed   20/25/33/50(internal)/50/66(internal)
Chip Set          FOREX
Max. Onboard DRAM 32MB
SRAM Cache        64/128/256KB
BIOS              AMI
Dimensions        330mm x 218mm
I/O Options       32-bit VESA card slots (2)
NPU Options       None

[Image]

                                CONNECTIONS

  Purpose                  Location     Purpose                 Location

  External battery            JP2       Turbo switch              JP15

  Reset switch                JP3       Turbo LED                 JP16

  Power LED & keylock         JP9       32-bit VESA local       S1 & S2
                                        bus slots

  Speaker                    JP10

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     Battery select internal                  JP2           pins 1 & 2
                                                              closed

      Battery select external                  JP2           connected

     Factory configured - do not alter        JP5            closed

     CMOS memory normal operation             JP6             open

      CMOS memory clear                        JP6            closed

      VESA bus select zero wait states        JP102          pins 1 & 2
       33MHz                                                 closed

      VESA bus select one wait state >        JP102          pins 2 & 3
      33MHz                                                   closed

      VESA bus speed select  33MHz           JP103          pins 1 & 2
                                                              closed

      VESA bus speed select > 33MHz           JP103          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

      5MB         (4) 256K x 9    (4) 1M x 9

      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

                          CPU SPEED CONFIGURATION

    CPU speed            JP7A              JP7B               JP7C

      50MHz           pins 2 & 3         pins 1 & 2         pins 2 & 3
                        closed            closed             closed

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

      25MHz           pins 1 & 2         pins 2 & 3         pins 1 & 2
                        closed            closed             closed

      20MHz           pins 2 & 3         pins 1 & 2         pins 1 & 2
                        closed            closed             closed

                          CPU TYPE CONFIGURATION

    CPU Type         JP12          JP13           JP29           JP30

    80486DX2      pins 1 & 2     pins 1 & 2    pins 1 & 2     pins 1 & 2
                    closed        closed         closed         closed

    ODP486SX      pins 1 & 2     pins 1 & 2    pins 2 & 3     pins 2 & 3
                    closed        closed         closed         closed

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

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

    80486SX       pins 2 & 3     pins 2 & 3    pins 2 & 3     pins 2 & 3
                    closed        closed         closed         closed

                            SRAM CONFIGURATION

    Size        Cache       Location        TAG      JP8A & D    JP8B & E
                SRAM

    64KB       (8) 8K x    Banks 0 & 1    (1) 8K x   pins 2 &    pins 2 &
                  8                          8          3           3

   128KB      (4) 32K x      Bank 0       (1) 8K x   pins 1 &    pins 1 &
                  8                          8          2           2

   256KB      (8) 32K x    Banks 0 & 1     (1) 32K   pins 2 &    pins 1 &
                  8                         x 8         3           2

  Note: Pins designated should be in the closed position.

