[a]
[b)---llii.im
Ic::::JI
./ f '" [d)
[e)
Fig. 2.6 Two SCSI devices on the SCSI bus
Deux dlspositifs SCSI sur Ie bus SCSI Zwel SCSI·Geriite auf dem SCSI·Bus
2-5 SeHing Up the SCSI Chain
The SCSI chain is the electronic data and control bus that connects two or more SCSI devices. As mentioned at the start of th is chapter, the SCSI chain can have multiple devices on the bus. Thus, the name " chain " implies the connection of these devices.
On any SCSI bus, there must be at least one SCSI initiator and one SCSI target. The
In certain cases, there can be more than one initiator on a bus, and in fact there are times when a computer can be an SCSI target device. These cases are rare and are not covered in this manual.
In each case, the SCSI ID's of each device must be unique.
Two SCSI devices
In the simplest case, only two devices share the SCSI chain. These are referred to as the SCSI initiator and the SCSI target. In our case, the SCSI initiator is the computer and the SCSI target is the scanner. This simple configuration is shown in Figure 2.6.
[a]Computer SCSI initiator (internally terminated)
[b]Scanner SCSI target
[c]SCSI terminator
[d]SCSI cable
In this case, both the SCSI initiator side of the bus and the SCSI target side of the bus have to be terminated, as shown in Figure 2.6.
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