ADIC SNC 5100 User Manual

Page of 228
SNC 5100 
26
Other Installation Issues
6-00020-02
The SCSI protocol also defines a priority-based arbitration method, based on 
the target ID of the device attaching to the bus. The SCSI ID priority order is, 
from highest to lowest, 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, 8.
Table of SCSI Terminology and Limitations
The following table (look for updates at http://www.scsita.org/) defines the 
number of devices supported, based on the negotiated transfer type. When 
reviewing the limitations of a bus, the capabilities of the fastest devices must be 
considered. The bus length indicates total SCSI bus length, including any 
internal device cables, rather than the length between any two devices. 
Table 5: SCSI Trade Association Terminology
Endorsed Terminology
for SCSI Parallel
Interface Technology
Max. Bus Speed, 
MB/Sec
Bus 
Width,
Bits
Max. 
Bus 
Lengths
,
in 
Meters 
(1)
Max.
Devices
LVD
SCSI 1 (2)
5
8
25
8
Fast SCSI (2)
10
8
25
8
Fast Wide SCSI (2)
20
16
25
16
Ultra SCSI (2)
20
8
25
8
Ultra SCSI (2) 
20
8
-
4
Wide Ultra SCSI
40
16
25
16
Wide Ultra SCSI
40
16
-
8
Wide Ultra SCSI
40
16
-
4
Ultra2 SCSI 
(2,3)
40
8
25
8
Wide Ultra2 SCSI 
(3)
80
16
25
16
Ultra3 SCSI or Ultra 160 
(5)
160
16
(4)
16
Ultra320
320
16
(4)
16