(1)SCSI bus configuration
Up to eight SCSI devices operating as an initiator or a target can be connected to the SCSI bus for the
For example, the system can be configured as
Using disconnect/reconnect function, concurrent input/output processing is possible on multi- SCSI devices.
(2)Addressing of peripheral device
Each SCSI device on the bus has its own unique address (SCSI ID:#n in Figure 1.1). For input/output operation, a peripheral device attached to the SCSI bus that operates as target is addressed in unit called as logical unit. A unique address (LUN: logical unit number) is assigned for each logical unit.
The initiator selects one SCSI device by specifying that SCSI ID, then specifies the LUN to select the peripheral device for input/output operation.
The HDD is constructed so that the whole volume of disk drive is a single logical unit, the selectable number of SCSI ID and LUN are as follows:
• | SCSI ID: | |
|
| |
• | LUN: | 0 (fixed) |
20 |
|