ADInstruments PowerLab/16SP, Owner'S Manual

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Chapter 2 — Setting Up 23
connected to a Windows computer (particularly internal ones), your
PC technical support person or IS manager may be able to help.
To confirm that you have set the right SCSI ID number, turn on the
PowerLab and watch to see if the Status indicator flashes yellow a
number of times equal to its SCSI ID number.
SCSI Termination Rules
Terminating the SCSI bus is essential to preserve the integrity of the
high-speed signals present on the bus. Termination helps keep these
signals free from noise and prevents unwanted signal reflections up
and down the bus. Without correct termination, the SCSI signals
could be swamped by reflections from previous signals, resulting in a
jumble of meaningless electronic noise. The way in which you
terminate the SCSI chain will depend on the number of SCSI devices
you wish to connect to your computer along with the PowerLab. The
SCSI connection between your PowerLab and computer is a very
good way to provide safe and reliable high-speed data transfer,
provided that you follow the rules for proper termination.
A SCSI chain is correctly terminated by placing terminators at each
end of the chain. The computer is terminated internally, so forming
one end of the chain. (A SCSI host adapter will be terminated: if the
SCSI controller and internal SCSI hard disk are both terminated, you
may have to alter things — see the documentation that came with the
card or computer.) The PowerLab should be at the other end of the
chain, with its SCSI termination switch on.
Connecting the PowerLab: Macintosh
Those Macintosh computers without USB (and even some with USB)
should have SCSI built in or available through a card. Not all SCSI
cards are suitable, especially high-end ones (ultra-wide SCSI and the
like). SCSI cards and cables with which the PowerLab should work
reliably are sold by ADInstruments. Make sure that you have the
correct, 25-pin to 25-pin SCSI cable to connect up your PowerLab.
(Most PowerBooks and Duo Docks have a special space-saving
square 29-pin SCSI connector, which requires another connector or
adapter. This can be purchased separately from your Apple dealer.)