Released
PMC-Sierra, Inc.
PM9311/2/3/5 ETT1™ CHIP SET
Data Sheet
PMC-2000164
ISSUE 3
ENHANCED TT1™ SWITCH FABRIC
1.10.3 AIB Links (A)
The inter-board device-to-device links are all AIB serial links. These serial links are full duplex with
1.6Gbits/s data in both directions. Each unidirectional link comprises three pairs of differential signals:
Even_Data, Odd_Data and Clock. The two data pairs carry link data while the clock provides
source-synchronous clock information. The clock is a 400MHz signal. Data is transmitted using both edges
of the clock to provide 800Mb/s on each of the two data pairs as shown in Figure 45.
Figure 45. AIB Links
Even_Data+
Even_Data-
Odd_Data+
Transmitter
Receiver
Odd_Data-
Clock+
Clock-
1.6 Gb/s
6
Transmitter
Receiver
Even_Data+
Odd_Data+
Clock+
The AIB links are very straightforward to use, and are the same in all four devices. After a link is first
enabled it will go through a training sequence with its peer. This is to ensure that the link is operating
correctly before data is transmitted. All data carried over AIB links are protected by a CRC field; the status
of the link is always visible to the local CPU via registers that can be accessed by the OOB bus.
The local CPU must configure all appropriate links before the links can operate. Figure 46 shows the AIB
control/status signals that are visible to the CPU.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
103
PMC [ PMC-SIERRA, INC ]
