Intergraph Fibre Channel, User Manual, Page: 62 / 84

FCAL LRC I/O Module
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1.6 FC-AL Interface
The (I/O) interface module provides an FC-AL interface via DB9 connectors for copper (Cu) cable connection.The
Tx/Rx interface has been wired to accept a Media Interface Adaptor (MIA), enabling the use of optical media
“Daisy chain” connection of multiple enclosures can be accommodated by linking between the FC-AL Tx connector
on one enclosure and the Tx/Rx connector on the next enclosure.
Each I/O or Loop Resiliency Circuit board houses Port Repeater chips that re-drive the Fibre Channel signals. Each
of the LRC I/O boards also houses a number o Port Bypass circuits. The function of these circuits is to bypass the
loop connections to empty drive bays or any disk drive which is not operating correctly
The two LRC I/O boards enable the dual loops within the enclosure to be maintained independently of one another,
for example: if a Port Bypass fails, that board may be replaced while the other loop is functioning normally.
Notes 1 A suitable dual loop host attachment will also be required to use this function.
2 There are no external terminators required with Fibre Channel architecture and any drive may be hot plugged
during operation.
1.6.1 Connecting Multiple Enclosures
A daisy chained loop application is used to connect multiple enclosures.
Standard DB9 FC-AL cables are used to link the Tx connector on one enclosure to the Tx/Rx connector of the next
and so on for the required number of enclosures in the chain, as shown in Figure 1–6 . The loop is completed by
linking the Tx connector on the last enclosure in the chain back to the host computer
Figure 1–5 LRC I/O Module: Rear Panel Layout
RS232
ID Range
FC-AL Tx/Rx FC-AL Tx
Active