Adaptec AHA-1510A - Manual (Page 37)

3-3
Hardware Installation
AHA-1510A/20A Series User’s Guide
Stock Number: 510400-00, Rev. C
Page: 3-3
Print Spec Number: 491842-00
Current Date: 11/18/94
ECN Date: 11/29/94
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The table below shows how termination must be set on the host
adapter for the three possible configurations of devices on the SCSI
bus. If you need to change the termination setting, follow the
instructions in Terminating the SCSI Bus on page 3-2.
The following sections explain each of the three configurations.
Termination for Internal Devices Only
When only internal devices are connected to the host adapter, the
last device connected to the ribbon cable should be terminated and
the host adapter should be terminated, as shown in Figure 3-2.
Devices Connected to Host Adapter Host Adapter Terminators
Internal devices only
(host adapter at end of cable) All three installed
External devices only
(host adapter at end of cable) All three installed
Internal and external devices
(host adapter in the middle) All three removed
Host adapter
Terminators installed
Internal device
No termination
Internal device
Termination enabled
Figure 3-2. Connecting Internal Devices Only