F-Tile Architecture and PMA and FEC Direct PHY IP User Guide
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A.6.3.4. F-Tile FGT Receiver Setting Recommendations
By default, Quartus® Prime Pro Edition software sets auto adaptation for all configurations of data rates, signaling mode (NRZ or PAM4) or data scrambling. With auto adaptation ON , links with all data rates across different reaches work with proper Transmitter equalizer settings.
As a rule of thumb, you can disable auto adaptation if your data rate is less than 7 Gbps for scrambled or unscrambled data. For data rates higher than 7 Gbps, if the data is unscrambled, you may disable auto adaptation. If the data rates are above 7 Gbps and the data is scrambled, you should leave auto adaptation ON.
| Data Rates (Gbps) | Signaling Mode | Adaptation Mode | Starting Point Setting | 
|---|---|---|---|
| <= 7 Gbps, unscrambled data | NRZ | Manual tuning | VGA Gain = 0 High frequency boost = 61 DFE tap 1 = 24 | 
| 9.8 Gbps CPRI, unscrambled data NRZ | NRZ | Manual tuning | VGA Gain = 17 High frequency boost = 34 DFE tap 1 = 0 | 
| 7-32 Gbps, scrambled data | NRZ | Auto adaptation | No RX equalization tuning needed | 
| 20-58.125 Gbps, scrambled data | PAM4 | Auto adaptation | No RX equalization tuning needed |