SCIENTIFIC MICRO SYSTEMS

OMTI 8620, OMTI 8627

Data bus:

16-bit, ISA

Size:

Full-length, full-height card

Hard drives supported:

OMTI 8620:Two MFM ST506/ST412 drives or ESDI drives

OMTI 8627:Two RLL ST506/ST412 or ESDI drives

Floppy drives supported:

Two 360KB, 720KB, 1.2MB, 1.44MB drives

Sector interleave:

1:1

Maximum heads/cyl.:

16 heads and 2048 cylinders

CONNECTIONS

Function

Location

34-pin control cable connecter-floppy drive

J1

34-pin control cable connecter-hard drive

J2

20-pin data cable connecter-drive 0

J3

20-pin data cable connecter-drive 1

J4

4-pin connecter-drive active LED

J5

USER CONFIGURABLE SETTINGS

Function

Location

Setting

»

Drive 1 set for fixed media drive

W4

open

 

Drive 1 set for removable media drive

W4

closed

»

Drive 1 set for ST506 drive

W5

open

 

Drive 1 set for ESDI drive

W5

closed

»

Drive 1 soft sectored

W6

open

 

Drive 1 hard sectored

W6

closed

»

Drive 0 set for fixed media drive

W7

open

 

Drive 0 set for removable media drive

W7

closed

»

Drive 0 set for ST506 drive

W8

open

 

Drive 0 set for ESDI drive

W8

closed

»

Drive 0 soft sectored

W9

open

 

Drive 0 hard sectored

W9

closed

 

If the drive on CN3 is a ESDI drive this trace must be cut

W12

open

 

If the drive on CN4 is a ESDI drive this trace must be cut

W13

open

»

Floppy drive port address is 3F0-3F7

W14

open

 

Floppy drive port address is 370-377

W14

closed

»

BIOS base address is C8000h

W15

open

 

BIOS base address is CA000h

W15

closed

»

BIOS enabled

W16

open

 

BIOS disabled

W16

closed

»

Factory configured - do not alter

W20

N/A

»

I/O speed set to high performance string mode

W21

open

 

I/O speed set to loop

W21

closed

»

If BIOS is #1002661, then drive 0 parameters are set to 4 hds. and 612 cyl. If BIOS is #1002662, then drive 0 parameter are set to 4 hds. and 615 cyl.

W22

open

»

Factory configured - do not alter

W22

closed

»

If BIOS is #1002661, then drive 1 parameters are set to 4 hds. and 612 cyl.If BIOS is #1002662, then drive 1 parameter are set to 4 hds. and 615 cyl.

W23

open

»

Factory configured - do not alter

W23

closed

SECTOR CONFIGURATION

Jumper W10

Jumper W11

BPS (ST506 only)

SPT- 8620

SPT- 8627

open

open

512

17

26

open

closed

512

17

26

closed

open

1024

18

26

closed

closed

1056

9

13

I/O PORT ADDRESS

Address

Jumper W17

Jumper W18

Jumper W19

320h

open

open

open

324h

open

open

closed

328h

open

closed

open

32Ch

open

closed

closed

1A0h

closed

open

open

1A4h

closed

open

closed

1A8h

closed

closed

open

1ACh

closed

closed

closed

DRIVE TYPE CONFIGURATION - #1002579

DRIVE 0

DRIVE 2

 

W20

W21

W22

W23

Cyl.

Hds.

closed

closed

closed

closed

ESDI

ESDI

open

closed

open

closed

987

7

closed

open

closed

open

918

15

open

open

open

open

612

4

DRIVE TYPE CONFIGURATION - #1002578

DRIVE 0

DRIVE 2

 

W20

W21

W22

W23

Cyl.

Hds.

closed

closed

closed

closed

ESDI

ESDI

open

closed

open

closed

820

6

closed

open

closed

open

1024

9

open

open

open

open

615

4