Fujitsu MAA3182, Руководство по эксплуатации продукта

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C141-E035-02EN 1 - 2
1.1 Standard Features
(1) Compactness
Since the SCSI controller circuit is embedded in the standard 3.5-inch 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/CCS standard
The IDD provides not only SCSI basic functions but also the following features:
•
Arbitration
•
Disconnection/reselection
•
Data bus parity
•
Command set which meets the logical specification of the SCSI CCS (Common
Command Set for Direct Access Device) requirements (Rev. 4.B)
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 width (16-bit SCSI), which have the wide transfer function suitable
for SCSI-3.
•
8-bit SCSI: Up to eight SCSI devices can be connected on the same SCSI bus.
•
16-bit SCSI: Up to 16 SCSI devices can be connected on the same SCSI bus.
For the ultra SCSI model, number of connectable SCSI devices on the same SCSI bus is varied
as follows.
•
Up to 4 SCSI devices having capacitance of 25 pF: Cable length of up to 3.0 m.
•
5 to 8 SCSI devices having capacitance of 25 pF: Cable length of up to 1.5 m
(4) High speed data transfer
•
8-bit SCSI: The data transfer rate on the 8-bit SCSI bus is 6 MB/s maximum in
asynchronous mode, 20 MB/s in synchronous mode.
•
16-bit SCSI: The data transfer rate on the 16-bit SCSI bus is 12 MB/s maximum in
asynchronous mode, 40 MB/s in synchronous mode.
Such a high data transfer rate on the SCSI bus can be useful with the large capacity buffer in
the IDD.