L- and H-Tile Transceiver PHY User Guide

ID 683621
Date 12/13/2024
Public
Document Table of Contents

5.1.1.2.3. Programmable Pre-Emphasis

Pre-emphasis can maximize the eye at the far-end receiver. The programmable pre-emphasis module in each transmit buffer amplifies high frequencies in the transmit data signal, to compensate for attenuation in the transmission media.
The pre-tap emphasizes the bit before the transition and de-emphasizes the remaining bits. A different polarity on pre-tap does the opposite.
Note: The Stratix® 10 L-Tile/H-Tile Pre-emphasis and Output Swing Estimator was created for the ES device family only. For L- and H-Tile Stratix® 10 production devices, you must use the L-Tile/H-Tile Transceiver Native PHY Stratix® 10 FPGA IP to verify the valid output swing level (VOD), pre-emphasis pre-tap and post tap settings under the Analog PMA Settings tab in the IP GUI. An invalid setting generates error messages under the System Messages pane.