Avago Technologies LSI53C180 - Manual (Page 12)

1-2 Introduction
Figure 1.1 LSI53C180 SCSI Bus Modes
Figure 1.1 shows the two SCSI bus modes available on the A or B Side.
LVD Link™ transceivers provide the multimode LVD or SE capability. The
LSI53C180 operates as both an expander and converter. In both SCSI
Bus Expander and Converter modes, cable segments are isolated from
each other. This feature maintains the signal integrity of each cable
segment.
Table 1.1 shows the types of operational modes for the LSI53C180.
The LSI53C180 provides additional control capability through the pin
level isolation mode (Warm Swap Enable). This feature permits logical
disconnection of both the A Side bus and the B Side bus without
disrupting SCSI transfers currently in progress. For example, devices on
the logically disconnected B Side can be swapped out while the A Side
bus remains active.
The LSI53C180 is based on previous bus expander technology, which
includes signal filtering along with retiming to maintain skew budgets.
The LSI53C180 is independent of software.
Table 1.1 Types of Operation
Signal Type Speed
LVD to LVD Ultra160
SE to SE Ultra
LVD to SE Ultra
SE to LVD Ultra
LSI53C180
SCSI Expander
192 PBGA
A Side B Side
LVD
SE
LVD
SE