Fujitsu MAS3184NC - Enterprise 18.4 GB Hard Drive, Product/Maintenance Manual

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1.1 Standard Features
(1) Compactness
Since the SCSI controller circuit is embedded in the standard 3.5 type fixed disk drive form factor,
the IDD is extremely compact. The IDD can be connected directly to the SCSI bus of the host
system.
(2) SCSI standard
The IDD provides not only SCSI basic functions but also the following features:
•
Arbitration
•
Disconnection/Reconnection
•
Data bus parity
The SCSI commands can manipulate data through logical block addressing regardless of the
physical characteristics of the disk drive. This allows software to accommodate future expansion
of system functions.
(3) 8-bit SCSI/16-bit SCSI
The IDD has 16-bit data bus width (16-bit SCSI), which have the wide transfer function suitable
for SCSI-2. 8-bit data bus is available only with NP model.
See subsection 5.3.2 for details of the bus width setting.
For the ultra SCSI model, number of connectable SCSI devices on the same SCSI bus is varied as
follows.
•
8-bit SCSI: 8 drives max. (option for NP model)
•
16-bit SCSI: 16 drives max.
(4) High speed data transfer
Such a high data transfer rate on the SCSI bus can be useful with the large capacity buffer in the
IDD.
•
8-bit SCSI: The data transfer rate on the SCSI bus is 40 MB/s maximum at the
synchronous mode.
•
16-bit SCSI: The data transfer rate on the SCSI bus is 320 MB/s maximum at the paced
transfer synchronous mode.