E-Tile Transceiver PHY User Guide

ID 683723
Date 7/08/2024
Public
Document Table of Contents

3.1.1.2. Gray Encoder/Precoder

PAM4 patterns generated in PAM4 mode are gray encoded by default. The encoding is as follows:

Table 39.  Gray Encoding
Linear Gray
00 00
01 01
10 11
11 10

The transmitter also includes a precoder that you can optionally enable for both PAM4 and NRZ signals. Once you turn it on, it performs 1/(1+D) encoding on all data bits until you disable it.