Commodore A4091 SCSI Adaptor

This page was added specifically because so many people appear not to actually have any documentation on the 4091. I know, because I'm the one who had to answer all the queries in #amiga on IRC :) The 4091 was licensed to DKB who built it for a while as well. This documentation refers specifically to the Commodore version as I'm not sure what changes DKB made to the design (if any.)

I'm trying not to break any copyright with Commodore's original documentation, but I do need to try to get the information across, so give me some leeway if I stray :)

Available topics are:


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Dipswitch Settings

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Pin outs

        1   Ground             26  /DB(0)
        2   Ground             27  /DB(1)
        3   Ground             28  /DB(2)
        4   Ground             29  /DB(3)
        5   Ground             30  /DB(4)
        6   Ground             31  /DB(5)
        7   Ground             32  /DB(6)
        8   Ground             33  /DB(7)
        9   Ground             34  /DB(P)
        10  Ground             35  Ground
        11  Ground             36  Ground
        12  Reserved           37  Reserved
        13  Open               38  TERMPWR
        14  Reserved           39  Reserved
        15  Ground             40  Ground
        16  Ground             41  /ATN
        17  Ground             42  Ground
        18  Ground             43  /BSY
        19  Ground             44  /ACK
        20  Ground             45  /RST
        21  Ground             46  /MSG
        22  Ground             47  /SEL
        23  Ground             48  /C/D
        24  Ground             49  /REQ
        25  Ground             50  /I/O
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Firmware Revisions

The most recent ROM is 40.13. Thanks to Paul Reeves of Asimware Innovations for that.

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General Questions

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Data not available. I've not opened up the 4000 recently to look at the names on the PCB :)

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