Avago Technologies LSI53C140 - Manual (Page 15)

Applications 1-5
Ver. 2.1 Copyright © 1998–2001 by LSI Logic Corporation. All rights reserved.
Figure 1.4 illustrates the cascading of the LSI53C140 to achieve four
distinct SCSI segments. Segments A and D can be treated as point-to-
point segments. Segments B and C are treated as load segments with
at least 8-inch spacing between every node.
Figure 1.4 LSI53C140 SCSI Bus Device
Table 1.2 SCSI Bus Distance Requirements
Segment Mode Length Limit
A LVD (Ultra2) 25 meters
SE (Ultra) 3 meters
1
1. The length may be more, possibly 6 meters, as no devices are attached to it.
HVD (Ultra) 25 meters
B LVD (Ultra2) 12 meters
SE (Ultra) 1.5 meters
HVD (Ultra 12 meters
C LVD (Ultra2) 12 meters
SE (Ultra) 1.5 meters
HVD (Ultra) 12 meters
Segment A Segment B Segment C
Primary Secondary
Shared Disk
SCSI Bus
Expander SCSI Bus
Expander
Server Server
SCSI Bus
Expander
Segment D
Subsystem
Shared Disk
Subsystem