DD & TT ENTERPRISE USA COMPANY

DT ESCORT SYSTEM BOARD A

Processor

80386SX/80486SLC

Processor Speed

25/33/40MHz

Chip Set

Symphony

Max. Onboard DRAM

16MB

Cache

None

BIOS

AMI

Dimensions

330mm x 218mm

I/O Options

Floppy drive interface, IDE interface, parallel port

Proprietary EISA riser card slot, PS/2 mouse port

Serial port (2), VGA port, video feature connector

NPU Options

80387SX/CX487SLC

CONNECTIONS

Purpose

Location

Purpose

Location

PS/2 mouse port

J2

Reset switch

J12A

Serial port (COM 1)

J3

Turbo switch

J12B

Serial port (COM 2)

J4

Turbo LED

J12C

Parallel port

J5

IDE interface LED

J12D

VGA port

J6

Not used

J12E

Floppy drive interface

J9

Speaker

J13A

Video feature port

J10

Power LED & keylock

J13B

IDE interface

J11

Proprietary riser card slot

S1

USER CONFIGURABLE SETTINGS

Function

Jumper

Position

»

Floppy drive disabled

E1

pins 1 & 3 closed

 

Floppy drive enabled

E1

pins 3 & 5 closed

 

Floppy drive address select 3FO-3F7

E1

pins 7 & 9 closed

 

Floppy drive address select 370-377

E1

pins 9 & 11 closed

»

IDE interface disabled

E1

pins 2 & 4 closed

 

IDE interface enabled

E1

pins 4 & 6 closed

 

IDE interface address 3FO-3F7, 1FO-1F7

E1

pins 8 & 10 closed

 

IDE interface address 370-377, 170-177

E1

pins 20 & 12 closed

»

On board video enabled

E2

pins 1 & 2, 3 & 4, 5 & 6 closed

 

On board video disabled

E2

pins 1 & 2, 3 & 4, 5 & 6 open

»

BIOS device select 1MB

E6

pins 1 & 2 closed

 

BIOS device select 2MB

E6

pins 3 & 5 closed

 

BIOS device select read only

E6

pins 2 & 4, 7 & 9, 8 & 10 closed

»

BIOS device select read/write

E6

pins 4 & 6, 9 & 11, 10 & 12

»

Chipset mode select 2x for 40MHz or less

E7

pins 3 & 5 closed

 

Chipset mode select 1x for true 50MHz only

E7

pins 1 & 3 closed

 

Chipset mode RDY1 set for 1X mode

E7

pins 4 & 6 closed

 

Chipset mode RDY2 set for 2X mode

E7

pins 2 & 4 closed

»

Chipset mode burst rate select 3-2-2-2

E8

pins 23 & 24 closed

 

Chipset mode burst rate select 2-1-1-1

E8

pins 23 & 24 open

»

Chipset mode write select 0 wait state

E8

pins 25 & 26 closed

 

Chipset mode write select 1 wait state

E8

pins 25 & 26 open

»

PS/2 mouse enable at IRQ12

E10

Closed

 

PS/2 mouse disable

E10

Open

»

CMOS memory normal

E11

Open

 

CMOS memory clear

E11

Closed

»

CPU speed select iOSC/2

E12

pins 2 & 3 closed

 

CPU speed select iOSC/1

E12

pins 1 & 2 closed

»

Factory configured - do not alter

E15

pins 1 & 2 closed

»

Factory configured - do not alter

E16/1, 3 & 5

pins 3 & 5 closed

»

Factory configured - do not alter

E16/2, 4, & 6

pins 4 & 6 closed

»

Factory configured - do not alter

E16/7, 9 & 11

pins 9 & 11 closed

»

Factory configured - do not alter

E16/7 & 8

Closed

»

Factory configured - do not alter

E16/8 & 10

N/A

»

Factory configured - do not alter

E16/11 & 12

Open

USER CONFIGURABLE SETTINGS (CONTINUED)

Function

Jumper

Position

»

Factory configured - do not alter

E16/13 & 14

Closed

»

Factory configured - do not alter

E16/15 & 16

Closed

»

Factory configured - do not alter

E16/17 & 18

Closed

Note: If there is no monochrome Hercules card present then the system will automatically assume that address 378h is LPT1 and address 278h is LPT2.

Pins designated should be in the closed position.

DRAM CONFIGURATION

Size

Bank 0

Bank 1

512KB

(2) 256K x 9

NONE

1MB

(2) 256K x 9

(2) 256K x 9

2MB

(2) 1M x 9

NONE

2.5MB

(2) 256K x 9

(2) 1M x 9

4MB

(2) 1M x 9

(2) 1M x 9

8MB

(2) 4M x 9

NONE

8.5MB

(2) 256K x 9

(2) 4M x 9

10MB

(2) 1M x 9

(2) 4M x 9

16MB

(2) 4M x 9

(2) 4M x 9

16MB

(2) 16M x 9

(2) 16M x 9

CPU SPEED CONFIGURATION

Speed

E14/pins 1 & 2

E14/pins 3 & 4

E14/pins 5 & 6

25MHz

Open

Closed

Closed

33MHz

Open

Closed

Open

40MHz

Open

Open

Closed

25MHz

Open

Closed

Closed

33MHz

Open

Closed

Open

SERIAL PORT A (J3) CONFIGURATION

COM

I/O Address

E5

»

COM1

3F8h

pins 3 & 5, 2 & 4, 7 & 8

 

COM3

3E8h

pins 1 & 3, 4 & 6, 7 & 8

 

COM4

2E8h

pins 3 & 5, 4 & 6, 7 & 8

 

Disabled

N/A

pins 1 & 3, 2 & 4

Note: pins designated should be in the closed position.

SERIAL PORT B (J4) CONFIGURATION

COM

I/O Address

E4

»

COM2

2F8h

pins 3 & 5, 2 & 4, 7 & 8

 

COM3

3E8h

pins 3 & 5, 4 & 6, 7 & 8

 

COM4

2E8h

pins 1 & 3, 4 & 6, 7 & 8

 

Disabled

N/A

pins 1 & 3, 2 & 4

Note:pins designated should be in the closed position.

PARALLEL PORT (J5) CONFIGURATION

COM

IRQ

I/O Address

E3

»

LPT1

IRQ7

3BCh

pins 3 & 5, 4 & 6, 7 & 8

 

LPT1

IRQ5

3BCh

pins 3 & 5, 4 & 6, 9 & 10

 

LPT2

IRQ7

378h

pins 3 & 5, 2 & 6, 7 & 8

 

LPT2

IRQ5

378h

pins 3 & 5, 2 & 6, 9 & 10

 

LPT3

IRQ7

278h

pins 1 & 3, 4 & 6, 7 & 8

 

LPT3

IRQ5

278h

pins 1 & 3, 4 & 6, 9 & 10

 

Disabled

N/A

N/A

pins 1 & 3, 2 & 4

Note: pins designated should be in the closed position.

VIDEO MEMORY CONFIGURATION

Size

Bank 0

Bank 1

512KB

(4) 44256

NONE

1024KB

(4) 44256

(4) 44256

Note: Bank 0 is permanently soldered onto the board.