GX4002 Datasheet, PDF (23/74 Pages) Gennum Corporation – Dynamic on-chip power management control

3.4 Crosspoint
The GX4002 provides eight different crosspoint paths, as shown in Table 3-6. The blocks
referenced in the different crosspoint paths are shown in Figure 3-5.
SDI0
EQ
Ch0 CDR
DR
SDO0
SDI1
LA
Ch1 CDR
DR
SDO1
Figure 3-5: Crosspoint Block Diagram
Table 3-6: Crosspoint Paths
Mode
1
2
3
4
5
6
7
8
Crosspoint Path
SDI1 =>LA=>DR=>SDO0
SDI1 =>LA=>CH1CDR=>DR=>SDO0
SDI1 =>LA=>CH0CDR=>DR=>SDO0
SDI1 =>LA=>CH1CDR=>CH0CDR=>DR=>SDO0
SDI0=>EQ=>DR=>SDO1
SDI0=>EQ=>CH0CDR=>DR=>SDO1
SDI0=>EQ=>CH1CDR=>DR=>SDO1
SDI0=>EQ=>CH0CDR=>CH1CDR=>DR=>SDO1
Reference
Figure 3-6
Figure 3-6
Figure 3-7
Figure 3-7
Figure 3-8
Figure 3-8
Figure 3-9
Figure 3-9
When the crosspoint is enabled, the standard data path is not interrupted. For example:
in Mode 1, the input to SDI1 will also be accessible at SDO1. When using crosspoint
modes, the automute feature for SDO1 or SDO0 may have to be disabled if the
corresponding SDI1 or SDI0 inputs are unused.
The relevant parameters in these registers and their values required to enable each of
the crosspoint options indicated above, are shown in Table 3-7.
The selection of a crosspoint path impacts the following feature:
• Polarity inversion
Table 3-7 also captures the impact on these features in each crosspoint mode.
GX4002 2x2 14.025Gb/s Crosspoint Switch with Trace
Equalization and Output De-Emphasis
Data Sheet
55972 - 0
March 2012
23 of 74
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