UNIDENTIFIED

COMPASS-486DX

Processor

80486SX/80487SX/80486DX/80486DX2

Processor Speed

25/33/50(internal)/66(internal)MHz

Chip Set

OPTI

Max. Onboard DRAM

32MB

Cache

64/128/256KB

BIOS

AMI

Dimensions

254mm x 218mm

I/O Options

None

NPU Options

None

CONNECTIONS

Purpose

Location

Purpose

Location

External battery

J9

Turbo switch

JP10

Speaker

J18

Turbo LED

JP11

Power LED & keylock

J19

Reset switch

SW1

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

CMOS memory normal operation

JP1

pins 2 & 3 closed

 

CMOS memory clear

JP1

pins 1 & 2 closed

 

Monitor type select monochrome

JP2

Open

 

Monitor type select color

JP2

Closed

 

Clock phase select double phase

JP4

pins 1 & 2 closed

 

Clock phase select single phase

JP4

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

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 CONFIGURATION

Size

Bank 0

Bank 1

TAG 0

TAG 1

64KB

(4) 8K x 8

(4) 8K x 8

NONE

(1) 8K x 8

128KB

(4) 32K x 8

NONE

NONE

(1) 8K x 8

256KB

(4) 32K x 8

(4) 32K x 8

(1) 8K x 8

(1) 8K x 8

CACHE JUMPER CONFIGURATION

Size

JP3

JP5

JP6

JP7

JP8

JP9

64KB

2 & 3

Open

Open

Open

Open

Open

128KB

1 & 2

Open

Open

Closed

Closed

Closed

256KB

2 & 3

Closed

Closed

Closed

Closed

Closed

Note: Pins designated should be in the closed position

CPU TYPE CONFIGURATION

Type

JP12

JP13

JP14

80486SX

pins 2 & 3 closed

Open

Open

80487SX

pins 1 & 2 closed

pins 2 & 3 closed

Closed

80486DX

pins 1 & 2 closed

pins 1 & 2 closed

Closed

80486DX2

pins 1 & 2 closed

pins 1 & 2 closed

Closed

MISCELLANEOUS TECHNICAL NOTE

Note: The location of pin 1 is unidentified.