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

CONNECTIONS

Purpose

Location

Purpose

Location

Speaker

J17

Keylock

J18 pin 9

Power LED

J18 pin 1

External battery connector

J22

Turbo LED

J18 pin 2

Speaker enable/disable switch

J23

Reset switch

J18 pin 6

32-bit external memory card

S1

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.