Adaptec AHA-1740A - Manual (Page 27)

Physical Installation in the System
The following steps should be followed to install the
AHA-1740A/1742A/1744 into the system:
1. Turn OFF the power to the computer system.
2. Remove the system cover according to the directions of
the computer manufacturer.
3. If only an external SCSI subsystem is used, no internal ca-
bling is required. If an internal SCSI peripheral is used,
install a 50-pin SCSI ribbon cable to the host adapter.
This cable must be oriented correctly. Pin 1 of the SCSI
cable is designated by a red strip. Multicolor 50-pin rib-
bon cables signify pin 1 with a brown color. Pin 1 on the
host adapter 50-pin SCSI header is located on the left-
hand side, farthest from the installation bracket and is
designated by the words PIN 1 on the board adjacent to
the header. After locating pin 1 on the host adapter and
on the SCSI cable, carefully insert the connector located
at the end of the long end of the cable into the host adapt-
er connector. After ensuring that all pins are lined up
and that the pin 1 orientation is correct, firmly seat the
connector to the board.
4. After installing the SCSI cable, the host adapter can be in-
stalled in any one of the 32-bit slots available in the host
computer. Some slots in EISA machines do not support
EISA bus mastering. The AHA-1740A/1742A/1744 can-
not be used in such slots. If the AHA-1740A/1742A/1744
is accidentally installed in such a slot, the EISA Configu-
ration program will report an error. A different slot must
be chosen for the AHA-1740A/1742A/1744.
5. If an internal SCSI device is to be used, it should be in-
stalled in the drive bays in accordance with the directions
on the peripheral. The proper power supply must be con-
nected to the SCSI peripheral device.
EISA-to-Fast SCSI Host Adapter Hardware Installation
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