Simulation Transmitter Emphasis And Receiver Equalization Settings; Figure 4-20: Magnitude (Db) Vs. Frequency (Hz) Response; For Rxfer[9:0] = 0001111111, 110110111 - Xilinx RocketIO X User Manual

R
Alternatively, the two groupings can be skewed to give very different frequency responses.
For example, setting RXFER[9:7] to the lowest frequency and RXFER[6:4] to the highest
frequency results in a flattened boost response.
Figure 4-20
RXFER[9:0]=0001111111 is compared with RXFER[9:0]=1101101111 for reference.
Simulation Transmitter Emphasis and Receiver Equalization
Settings
Note:
The RocketIO X transceiver incorporates pre-emphasis in the transmitter which
preemptively corrects for the PCB loss. In addition, there is an equalizer in the receiver
which can post-process the signal to correct for the same loss. Proper transmitter and
receiver settings can essentially null the lossy attenuation effects of a PCB completely.
This section provides some good estimates for settings to transfer signals over long,
medium, and short backplane lengths, including different lengths of FR4 as well as two
backplane connectors. The signal path represents the path from one line/switch card to
another through a backplane. Users must be sure to use a connector that reliably passes a
signal at operation speed. See
112
shows such an example where the frequency response for

Figure 4-20: Magnitude (dB) vs. Frequency (Hz) Response

for RXFER[9:0] = 0001111111, 110110111

This section uses simulation numbers only.
1-800-255-7778
Chapter 4: Analog Design Considerations
Table 4-9.
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ug035_ch4_20b_111003
RocketIO™ X Transceiver User Guide
UG035 (v1.5) November 22, 2004