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    SubjectRe: [OT] SCSI Printer on AIC78XX without SCSI Terminator
    First, normal (non-differential) SCSI is an OpenCollector bus design
    which simply wont work without a terminator and is designed to use
    exactly two(2) terminators, one at each end of the bus, these both
    provide a pull up and terminate the bus to prevent reflections. Also
    the longer and faster the bus the more you depend on correct termination
    e.g. 130 ohm - +3.3V

    For much more detail, including external terminators please see

    http://www.scsita.org/aboutscsi/SCSI_Termination_Tutorial.html

    Second, there is usually a built in terminator in the AIC7xxx
    adaptor, usually enabled in the SCSI BIOS.

    Also check your device for negotiable SCSI options, eg SYNC, OFFSET

    Gustavo Guillermo Pérez wrote:
    > Hello, I was tried to use a SCSI Printer, onto a AIC78XX (old and new driver),
    > when driver load, it recognise the Scanner, the Printer and Panel, but may be
    > the copier doesn't have an internal terminator, and driver hangs forever
    > discovering unexistent 4th device. I do not wish to dissasemble the copier to
    > solder the terminator, and I never deal with SCSI HW. Kernel I was tried:
    > 2.6.7, 2.4.23. but I think the driver does not change from 2.6.7 to 2.6.12.
    >
    > I see the doc about this driver but I can't figure out wich of a lot options
    > can help to not try to discover more than 3 devices... I'll have a chance to
    > play with this machine the next week, then I'm taking ideas.
    >
    > aic7xxx=seltime:2
    > this option wait for answer but the device 4º waits forever...
    > aic7xxx=no_reset
    > I don't....
    > aic7xxx=override_term
    > mmmmmm
    > ...
    >
    > The new driver support cmdline args?
    >
    > If someone can share comment I would appreciate it
    >
    > cheers

    --
    mit freundlichen Grüßen, Brian.

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