Altera Stratix GX Transceiver - Manual (Page 116)

5–4 Altera Corporation
Stratix GX Transceiver User Guide January 2005
Introduction
Figure 5–2. Example of Mapping XGMII Characters to PCS Code-Groups
The PCS code-groups are sent via PCS ordered sets. PCS ordered sets
consist of combinations of special and data code-groups defined as a
column of code-groups. These ordered sets are composed of four code-
groups beginning in lane 0.
Table 5–2 lists the defined idle ordered sets
(||I||) that are used for the self managed properties of XAUI.
This section briefly introduces XAUI, along with the code-groups and
ordered sets associated with this self-managed interface. For full details
on the XAUI standard, refer to clauses 47–48 in the 10 Gigabit Ethernet
standard (IEEE 802.3ae).
XAUI mode enables the configuring of transceiver blocks to support
XAUI synchronization, channel alignment, rate compensation, XGMII to
PCS code-group conversion, and PCS code-group-to-XGMII conversion.
This section describes the supported digital architecture, clocking
schemes, and software implementation of the XAUI mode.
Figure 5–3
shows a block diagram of a duplex channel configured in XAUI mode.
XGMII
PCS
Lane 0
T/RXD<7..0>
T/RXD<15..8>
T/RXD<23..16>
T/RXD<31..24>
Lane 1
Lane 2
Lane 3
K R
S
Dp
D ---
A
I T D
D
D D
D
D
D D
D
D
D
D
D
D
D
D
D D
D
D
D D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
D
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I Ds
Dp
Dp
Dp
Dp
Dp ---
---
---
---
---
---
---
Dp
Dp
Dp
Dp
Dp
Dp K
K
K
R
R
R Ds
S D
T
K
K
K
K
K
K
K
K
K
K
R
R
R
R
R
R
R
R
R
R
R
R
A
A
A
Table 5–2. Defined Idle Ordered Set
Code Ordered_Set
Number of
Code_Groups
Encoding
||I| Idle Substitute for XGMII Idle
||K|| Sync column 4 /K28.5/K28.5/K28.5/K28.5/
||R|| Skip column 4 /K28.0/K28.0/K28.0/K28.0/
||A|| Align column 4 /K28.3/K28.3/K28.3/K28.3/