Alfa Data: Oktagon 2008
BSC: Oktagon 2008
Connection: Zorro II

Image of a Rev 3 card
Image of a Rev 3 card

Image of a Rev 7 card
Image of a Rev 7 card

Image of a Rev 7 card, Front
Image of a Rev 7 card, Front

Rear image of a Rev 7 card
Rear image of a Rev 7 card

Hi Res Version, Image of a Rev 3 card - 1407K
Hi Res Version, Rev 7 - 130K
Hi Res Version, Image of a Rev 7 card, Front - 1609K
Hi Res Version, Rev 7 Back - 72K
Image of Oktagon 2008 box - 35K

The Oktagon 2008 is a full length Zorro II SCSI-2 card which provides an external DB25 SCSI connector, an internal 50pin SCSI connector and enough space to mount a hard drive directly onto the card. The Oktagon also has the ability to accept additional RAM in the form of 1Mx4 ZIP chips. Oktagon ROM versions of less than 6.5 may have problems with removable media devices. The recommended version is 6.8. To see the current ROM version number, press F1 during powerup, or use C:Version on oktagon.device. Problems have been reported using the Oktagon with 68060 accelerator boards. The Oktagon ROM uses a MOVEP operation, which is an illegal instruction on the 68060. An A4000 with a 68060 board and the Oktagon will refuse to boot because of this problem. Revisions 6.10 and 6.12 of the Oktagon ROM correct this problem. There is a "Multi Initiator" option in the Oktagon preferences program. Enabling this will prevent the board from sending resets to other SCSI devices, which may help when sharing peripherals between multiple computers. There is also an option to disable parity checking, which may be necessary for using older SCSI devices that don't support parity. WARNING: Connecting the SCSI cable the wrong way around may lead to diode D301 burning out. This can be replaced with an 1N4001 or 1N4007.

Board Layout
| Jumper |___
| : :::::: :: SCSI |
|LED 123456 :: Connector |
| :: |#
| ::::::: 63,83 :: |# External
| ::::::: 23,43 :: |# SCSI
| ::::::: 62,82 :: |# Port
| ::::::: 22,42 :: |# (DB25)
| ::::::: 61,81 :: |#
| ::::::: 21,41 :: |
| ::::::: 60,80 . |
| ::::::: 20,40 : Power |
||||||||||||||||||||||||||| |


1: SCSI Enable/Disable (Open: SCSI enabled, Closed: SCSI disabled)
(On the IDE version, this enables or disables the IDE port.)
2: Memory Enable/Disable (Open: Memory enabled, Closed: Memory disabled)
3: MS0 (see below)
4: MS1 (see below)
5: Test Mem (Open: Autoconfig, Closed: Don't autoconfig)
6: Terminator Power (Open: None, Closed: Supply +5V SCSI term power)

Memory Size Configuration

Memory Size MS0 MS1 Chips Added To Sockets
----------- ----- ------ ----------------------

2M Open Open 20,21,22,23

4M Closed Open 40,41,42,43

6M Open Closed 60,61,62,63

8M Closed Closed 80,81,82,83

Contributions to this page by:
Andreas Kähler, Jürgen Weiß, Michael Czajka, RiWa & Friends, Robert Williams

Einem link gefolgt? Hier gehts zur Hauptseite

Followed a link? Please go to the Main Site