Adaptec AHA-1740A - Manual (Page 28)

6. The 50-pin SCSI ribbon cable can now be attached to each
SCSI device. Refer to the device’s installation instruc-
tions to ensure proper pin 1 orientation. Pin 1 orientation
must be consistent throughout the system. Keep the rib-
bon cable neatly dressed away from the ventilation slots
in the computer system. Keep the ribbon cable dressed
away from possible electrical noise sources or noise sensi-
tive components, particularly large microprocessors, mem-
ory boards, switching power supplies, and analog data
acquisition boards. If the internal configuration requires
the cable to come near noise sensitive circuits, make sure
that the cable crosses the boards at right angles and is
near the noise sensitive circuits for the shortest distance
possible.
WARNING
The AHA-1740A/1742A requires single-ended devices.
The AHA-1744 requires differential devices. Failure
to match drive types can result in electrical damage to
the host adapter and the peripherals.
7. Carefully reinstall the cover of the computer.
8. If an external SCSI subsystem is to be installed, it can
now be cabled to the external SCSI connector projecting
from the shielding bracket on the back of the AHA-
1740A/1742A/1744 Host Adapter. The proper shielded
SCSI cable must be used for proper operation. The exter-
nal connector on the AHA-1740A/1742A/1744 is a 50-pin
high density type connector that ensures correct pin 1 ori-
entation on the host adapter. The subsystem, cables, and
SCSI terminators must be installed in accordance with
the directions provided with the external SCSI subsys-
tem. The addresses selected for external SCSI devices
must not overlap with the addresses of the host adapter
or any other SCSI devices attached internally.
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adaptec AHA-1740A/1742A/1744
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