COMPAQ COMPUTER CORPORATION

DESKPRO 286 (12MHz)

Processor

80286

Processor Speed

12MHz

Chip Set

ETEQ

Max. Onboard DRAM

2.125MB

Cache

None

BIOS

Compaq

Dimensions

330mm x 218mm

I/O Options

None

NPU Options

80287

CONNECTIONS

Purpose

Location

Purpose

Location

Fixed drive power

J109

Proprietary keyboard connector

J116

Fixed drive/Tape backup power

J110

Main power

J117

Floppy drive power

J111

External battery

J118

Floppy drive power

J112

Keylock

J119

Monitor power

J113

Onboard power LED

LED1

Speaker

J115

 

 

USER CONFIGURABLE SETTINGS

Function

Jumper/Switch

Position

»

Oscillator type select single package

E3

Closed

 

Oscillator type select dual package

E3

Open

»

Memory operation generation select discrete gate

E4

pins 1 & 2 closed

 

Memory operation generation select CBC internal

E4

pins 2 & 3 closed

»

Auto slowdown disabled in software

E5

pins 1 & 2 closed

 

Auto slowdown enabled in software

E5

pins 2 & 3 closed

»

CPU speed select switchable at keyboard

SW1/6

Off

 

CPU speed select forced slow

SW1/6

On

»

Factory configured - do not alter

SW1/7

Off

»

Monitor type select color

SW1/8

On

 

Monitor type select monochrome

SW1/8

Off

 

Notes: Settings for E3, E4, and E5 are accomplished by cutting the conductors on the bottom of the board and re-soldering the indicated locations.

WARNING: Modifying E3, E4, or E5 will void the manufacturers warranty!

DRAM CONFIGURATION

Size

Bank 0

P-0

Bank 1

Bank 2

Bank 3

Bank 4

256KB

(4) 4464

(2) 4164

(18) 4164

NONE

NONE

NONE

512KB

(4) 4464

(2) 4164

(18) 4164

(18) 4164

(18) 4164

NONE

640KB

(4) 4464

(2) 4164

(18) 4164

(18) 4164

(18) 4164

(18) 4164

640KB

(4) 4464

(2) 4164

(18) 41256

NONE

NONE

NONE

1.125MB

(4) 4464

(2) 4164

(18) 41256

(18) 41256

NONE

NONE

1.625MB

(4) 4464

(2) 4164

(18) 41256

(18) 41256

(18) 41256

NONE

2.125MB

(4) 4464

(2) 4164

(18) 41256

(18) 41256

(18) 41256

(18) 41256

DRAM SWITCH CONFIGURATION

Size

SW1/1

SW1/2

SW1/3

SW1/4

SW1/5

Disabled

N/A

On

On

N/A

N/A

256KB

On

On

Off

Off

Off

512KB

On

Off

On

Off

Off

640KB

On

Off

Off

Off

Off

640KB

Off

Off

Off

On

On

1.125MB

Off

Off

Off

On

Off

1.625MB

Off

Off

Off

Off

On

2.125MB

Off

Off

Off

Off

Off

Notes: Closing both SW1/switch 2 and SW1/switch 3, disables banks 0 & 1 and any onboard ROM.

ROM JUMPER CONFIGURATION

ROM type

Size

BIOS ROM/E1

ROM set 2/E2

Static

8K x 8

1 & 2, 4 & 5, 7 & 8

1 & 2, 4 & 5, 7 & 8

Static

16K x 8

2 & 3, 4 & 5, 7 & 8

2 & 3, 4 & 5, 7 & 8

Static

32K x 8

2 & 3, 4 & 5, 7 & 8

2 & 3, 5 & 6, 7 & 8

Dynamic

8K x 8

1 & 2, 4 & 5, 8 & 9

1 & 2, 4 & 5, 8 & 9

Dynamic

16K x 8

2 & 3, 4 & 5, 8 & 9

2 & 3, 4 & 5, 8 & 9

Dynamic

32K x 8

2 & 3, 5 & 6, 8 & 9

2 & 3, 5 & 6, 8 & 9

Notes: Settings are accomplished by cutting the conductors on the bottom of the board and re-soldering the indicated locations. Pins designated should be in the closed position.

WARNING: Modifying the factory configurations will void the manufacturers warranty!