
EVEREX SYSTEMS, INC.

SYSTEM 3900 (EV-1851)

Processor         80386DX
Processor Speed   25/33MHz
Chip Set          C & T
Max. Onboard DRAM 8MB
Cache             64KB
BIOS              AMI
Dimensions        355mm x 304mm
I/O Options       32-bit external memory card slot
NPU Options       80387/3167

[Image]

                                CONNECTIONS

  Purpose              Location    Purpose                      Location

  Speaker                J17       Keylock                      J18 pin 9

  Power LED            J18 pin 1   External battery               J22
                                   connector

  Turbo LED            J18 pin 2   Speaker enable/disable         J23
                                   switch

  Reset switch         J18 pin 6   32-bit external memory          S1
                                   card

                        USER CONFIGURABLE SETTINGS

                Function                     Jumper          Position

     DRAM speed select 4 wait states          J15           pins 1 & 2
                                                              closed

      DRAM speed select 3 wait states          J15           pins 2 & 3
                                                              closed

     NPU mode select 1 wait state             J16           pins 1 & 2
                                                              closed

      NPU mode select 0 wait states            J16           pins 2 & 3
                                                              closed

     Factory configured - do not alter        J19             Open

                            DRAM CONFIGURATION

     Size         Bank 0         Bank 1         Bank 2         Bank 3

     1MB        (4) 256K x 9      NONE           NONE           NONE

     2MB        (4) 256K x 9   (4) 256K x 9      NONE           NONE

     4MB        (4) 256K x 9   (4) 256K x 9  (4) 256K x 9   (4) 256K x 9

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

     8MB        (4) 1M x 9     (4) 1M x 9        NONE           NONE

     16MB       (4) 1M x 9     (4) 1M x 9     (4) 1M x 9     (4) 1M x 9

  Note:Banks 2 & 3 are used when a 32-bit external memory card is
  installed.

                     CACHE CONFIGURATION

             Size                         Bank 0

             64KB                       (8) 64K x 1

  Note:Cache is factory installed and is not configurable.

                            CMOS CONFIGURATION

  Setting     W1      W2      W3      W4     W5      W6      W7      W8

  Internal   2 & 3   2 & 3   2 & 3   2 & 3  2 & 3   2 & 3   2 & 3   2 & 3

  External   1 & 2   1 & 2   1 & 2   1 & 2  1 & 2   1 & 2   1 & 2   1 & 2

  Note: Pins designated should be in the closed position.

