HwMuseum | Index

COMPUTREND SYSTEMS, INC.

UMC-386 (MS-3131 Ver. 1.1)

Processor

80386DX

Processor Speed

33/40MHz

Chip Set

UMC

Max. Onboard DRAM

32MB

SRAM Cache

32/64/128/256KB

BIOS

AMI

Dimensions

220mm x 220mm

I/O Options

Auxiliary keyboard connector

NPU Options

80387

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J1

Turbo switch

J2/15 - 17

Power LED & keylock

J2/1 - 5

Turbo LED

J2/12 & 13

Speaker

J2/7 - 10

Auxiliary keyboard

KB2

Reset switch

J2/19 & 20

   

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Monitor type select monochrome

JP1

open

 

Monitor type select color

JP1

closed

»

NPU disabled

JP3

JP9

open

open

 

NPU endabled

JP3

JP9

closed

closed

»

Battery select internal

J1

pins 2 & 3 closed

 

battery select external

J1

connected

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

32MB

(4) 4M x 9

(4) 4M x 9

CACHE JUMPER CONFIGURATION

Size

JP4

JP5

JP6

JP7

JP8

JP11

JP12

JP13

32KB

open

open

pins 2 & 3

pins 1 & 2

pins 1 & 2

pins 2 & 3

pins 1 & 2

open

64KB

open

open

pins 2 & 3

pins 1 & 2

pins 1 & 2

pins 1 & 2

pins 2 & 3

closed

128KB

closed

open

pins 1 & 2

pins 2 & 3

pins 1 & 2

pins 1 & 2

pins 2 & 3

closed

256KB

closed

closed

pins 2 & 3

pins 2 & 3

pins 2 & 3

pins 1 & 2

pins 2 & 3

closed

Note:Pins designated should be in the closed position.

CACHE CONFIGURATION

Size

Cache SRAM

Location

TAG

32KB

(4) 8K x 8

Bank 0

(1) 8K x 8

64KB

(8) 8K x 8

Banks 0 & 1

(1) 8K x 8

128KB

(4) 32K x 8

Bank 0

(1) 8K x 8

256KB

(8) 32K x 8

Banks 0 & 1

(1) 32K x 8