(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 8-bit SCSI and up to 16 SCSI devices operating as an initiator or a target can be connected to the SCSI bus for the 16-bit SCSI in any combination.

For example, the system can be configured as multi-host system on which multiple host computers that operate as initiator or connected through the SCSI bus.

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:

8-bit SCSI:Selectable from 0 to 7 (option for NP model, switch selectable)

 

 

16-bit SCSI:Selectable from 0 to 15 (switch selectable)

LUN:

0 (fixed)

20

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Fujitsu MBA3073NP, MBA3073NC, MBA3300NP, MBA3147NC, MBA3300NC, MBA3147NP manual Scsi ID, Lun