Single ended and differential scsi buses, Maximum cable length for scsi standards – LSI MegaRAID Express 500 User Manual
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MegaRAID Express 500 Hardware Guide
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Single Ended and Differential SCSI Buses
The SCSI standard defines two electrical buses:
• a single ended bus
• low-voltage differential bus
Maximum Cable Length for SCSI Standards
Standard
Single ended
LVD
Maximum Number of
Drives
SCSI I
6 m
12 m
7
Fast SCSI
6 m
12 m
7
Fast Wide SCSI
6 m
12 m
15
Ultra SCSI
1.5 m
12 m
7
Ultra SCSI
3 m
12 m
3
Wide Ultra SCSI
12 m
15
Wide Ultra SCSI
1.5 m
12 m
7
Wide Ultra SCSI
3 m
12 m
3
Ultra 2 SCSI
25 m
1
Ultra 2 SCSI
12 m
7
Wide Ultra 2 SCSI
25 m
1
Wide Ultra 2 SCSI
12 m
15
Ultra3 SCSI
25m
1
Ultra3 SCSI
12m
7
Wide Ultra3 SCSI
25m
1
Wide Ultra3 SCSI
12m
15
SCSI Bus Widths and Maximum Throughput
SCSI Standard
SCSI Bus Width
SCSI Throughput
SCSI I
8 bits
5 MB/s
Fast SCSI
8 bits
10 MB/s
Fast Wide SCSI
16 bits
20 MB/s
Ultra SCSI
8 bits
20 MB/s
Wide Ultra SCSI
16 bits
40 MB/s
Ultra 2 SCSI
8 bits
40 MB/s
Wide Ultra 2 SCSI
16 bits
80 MB/s
Ultra3 SCSI
8 bits
80 MB/s
Wide Ultra3 SCSI
16 bits
160 MB/s