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OMTI 8640

SCIENTIFIC MICRO SYSTEMS

OMTI 8640

Data bus: 16-bit, ISA

Size: Full-length, full-height card

Hard drives supported: Two ESDI RLL drives

Floppy drives supported: Four 360KB, 720KB, 1.2MB,or 1.44MB

Sector interleave: 1:1

Maximum heads/cyl.: 16 heads and 2048 cylinders

CONNECTIONS

Function

Location

34-pin data cable connector-floppy drive 1 & 2

J1

34-pin data cable connector-floppy drive 3 & 4

J2

20-pin data cable connector-drive 0

J3

20-pin data cable connector-drive 1

J4

34-pin control cable connector-hard drive

J5

4-pin connector-drive active LED

J6

USER CONFIGURABLE SETTINGS

Function

Location

Setting

Floppy drive port address is 3F0-3F7h

W2

open

 

Floppy drive port address is 370-377h

W2

closed

Hard drive port address is 1F0-1F7h

W3

open

 

Hard drive port address is 170-177h

W3

closed

Floppy enabled

W5

open

 

Floppy drive disabled

W5

closed

SPT-read from drive

W16

open

 

SPT-calculate and set

W16

closed

Cache disabled

W17

open

 

Cache enabled

W17

closed

Track Offset Cmd. and Data Strobe Offset disabled

W18

open

 

Track Offset Cmd. and Data Strobe Offset enabled

W18

closed

Single speed floppy drive supported

W19

open

 

Dual speed floppy drive Supported

W19

closed

Floppy connector (CN1) polarity active high

W20

pins 1 & 2 closed

 

Floppy connector (CN1) polarity active low

W20

pins 2 & 3 closed

Floppy connector (CN1) polarity active high

W21

pins 1 & 2 closed

 

Floppy connector (CN1) polarity active low

W21

pins 2 & 3 closed

BIOS enabled

W25

closed

 

BIOS disabled

W25

open

Chassis not grounded

W28

open

 

Chassis grounded

W28

closed

Note:W22, & W11-15 are not documented

BIOS ADDRESS

Address

Jumper W23

Jumper W24

C8000h

closed

closed

 

CA000h

closed

open

 

CC000h

open

closed

 

CE000h

open

open