HwMuseum | Index

COMMODORE BUSINESS MACHINES, INC.

386DX System (Part #368954-01)

Processor

80386DX

Processor Speed

25/33MHz

Chip Set

PC CHIPS

Max. Onboard DRAM

32MB

SRAM Cache

64/128/256KB

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial port (2), VGA port

NPU Options

80387/3167

CONNECTIONS

Purpose

Location

Purpose

Location

VGA port

C1

PS/2 style mouse port

C5

Serial port 1

C2

Floppy drive interface

C6

Serial port 2

C3

Hard drivve interface

C7

Parallel port

C4

Basic connectors (pins unknown)

C8

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Combined BIOS enabled

J7

closed

 

Combined BIOS disabled

J7

open

»

Monitor type select color

J14

J20

pins 1 & 2 closed

pins 2 & 3 closed

 

Monitor type select color disabled

J14

J20

pins 2 & 3 closed

pins 1 & 2 closed

»

Factory configured - do not alter

J17

unknown

»

Factory configured - do not alter

J18

unknown

»

Factory configured - do not alter

J19

unknown

»

Factory configured - do not alter

J31

unknown

»

VGA select zero wait states

J23

closed

 

VGA select zero wait states disabled

J23

open

»

Monitor type select monochrome

J30

open

 

Monitor type select monochrome disabled

J30

closed

»

Floppy drive interface (C6) enabled

J41

pins 1 & 2 closed

»

Floppy drive interface (C6) disabled

J41

pins 2 & 3 closed

»

Hard drive interface (C7) enabled

J43

J44

closed

closed

 

Hard drive interface (C7) disabled

J43

J44

open

open

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

5MB

(4) 256K x 9

(4) 1M x 9

5MB

(4) 1M x 9

(4) 256K x 9

8MB

(4) 1M x 9

(4) 1M x 9

16MB

(4) 4M x 9

NONE

17MB

(4) 256K x 9

(4) 4M x 9

17MB

(4) 4M x 9

(4) 256K x 9

20MB

(4) 1M x 9

(4) 4M x 9

20MB

(4) 4M x 9

(4) 1M x 9

32MB

(4) 4M x 9

(4) 4M x 9

SERIAL PORT CONFIGURATION

Function

Jumper

Position

»

Serial port 1 (C2) enabled at interrupt IRQ4

J27

closed

 

Serial port 1 (C2) disabled

J27

open

»

Serial port 2 (C3) enabled at interrupt select IRQ3

J29

closed

 

Serial port 2 (C3) disabled

J29

open

 

 

Serial port 1 (C2) select COM1

J38

J39

J40

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

 

 

Serial port 2 (C3) select COM2

J38

J39

J40

pins 1 & 2 closed

pins 1 & 2 closed

pins 1 & 2 closed

 

 

Serial port 1 (C2) select COM2

J38

J39

J40

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

 

 

Serial port 1 (C2) select COM1

J38

J39

J40

pins 1 & 2 closed

pins 1 & 2 closed

pins 2 & 3 closed

 

 

Serial port 1 (C2) select COM1

J38

J39

J40

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

 

 

Serial port 2 (C3) disabled

J38

J39

J40

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

 

 

Serial port 1 (C2) disabled

J38

J39

J40

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

 

 

Serial port 2 (C3) select COM1

J38

J39

J40

pins 1 & 2 closed

pins 2 & 3 closed

pins 2 & 3 closed

 

 

Serial port 1 (C2) disabled

J38

J39

J40

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

 

 

Serial port 2 (C3) select COM2

J38

J39

J40

pins 1 & 2 closed

pins 2 & 3 closed

pins 1 & 2 closed

 

 

Serial port 1 (C2) select COM2

J38

J39

J40

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

 

 

Serial port 2 (C3) disabled

J38

J39

J40

pins 2 & 3 closed

pins 1 & 2 closed

pins 2 & 3 closed

 

 

Serial port 1 & 2 disabled

J38

J39

J40

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

PARALLEL PORT CONFIGURATION (C4)

Function

Jumper

Position

»

Parallel port enabled at IRQ7

J28

pins 2 & 3 closed

 

Parallel port enabled at IRQ5

J28

pins 1 & 2 closed

 

Parallel port enable LPT1

J36

J37

pins 2 & 3 closed

pins 1 & 2 closed

 

Parallel port enable LPT2

J36

J37

pins 1 & 2 closed

pins 1 & 2 closed

 

Parallel port enable LPT3

J36

J37

pins 1 & 2 closed

pins 2 & 3 closed

 

Parallel port disabled

J36

J37

pins 2 & 3 closed

pins 2 & 3 closed

SRAM JUMPER CONFIGURATION

Size

Jumper J8

Jumper J9

Jumper J11

Jumper J12

Jumper J13

Jumper J15

Jumper J16

Jumper J42

Disabled

closed

pins 1 & 2 closed

pins 1 & 2 closed

N/A

N/A

open

N/A

N/A

64KB

closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

pins 1 & 2 closed

closed

pins 2 & 3 closed

pins 1 & 2 closed

128KB

closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

closed

open

pins 2 & 3 closed

256KB

closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 2 & 3 closed

pins 1 & 2 closed

closed

pins 1 & 2 closed

pins 2 & 3 closed

SRAM CONFIGURATION

Size

Cache SRAM

Location

TAG (UAA)

TAG (U11)

64KB

(8) 8K x 8

Banks 0 & 1

(1) 8K x 8

(1) 8K x 8

128KB

(4) 32K x 8

Bank 0

(1) 32K x 8

NONE

256KB

(8) 32K x 8

Banks 0 & 1

(1) 32K x 8

(1) 32K x 8

VIDEO SWITCH CONFIGURATION (SW1)

Mode

switch 1

switch 2

switch 3

switch 4

switch 5

56Hz vertical refresh

open

open

N/A

N/A

N/A

60Hz vertical refresh

open

closed

N/A

N/A

N/A

72Hz vertical refresh

closed

open

N/A

N/A

N/A

Enable interlaced

N/A

N/A

open

open

N/A

60Hz non-interlaced

N/A

N/A

open

closed

N/A

72Hz non-interlaced

N/A

N/A

closed

open

N/A

31.5KHz horizontal scan rate

N/A

N/A

N/A

N/A

open

40KHz horizontal scan rate

N/A

N/A

N/A

N/A

closed

VRAM CONFIGURATION

Size

VRAM

SW1/switch 6

512KB

(2) 256K x 4

closed

1MB

(4) 256K x 4

open