L- and H-Tile Transceiver PHY User Guide

ID 683621
Date 12/04/2024
Public
Document Table of Contents

2.4.2.3.1. 8B/10B Encoder and Decoder

To enable the 8B/10B Encoder and the 8B/10B Decoder, select the Enable TX 8B/10B Encoder and Enable RX 8B/10B Decoder options on the Standard PCS tab in the IP Editor. Platform Designer allows implementing the 8B/10B decoder in RX-only mode.

The following ports are added:

  • tx_datak
  • rx_datak
  • rx_runningdisp
  • rx_disperr
  • rx_errdetect

rx_datak and tx_datak indicate whether the parallel data is a control word or a data word. The incoming 8-bit data (tx_parallel_data) and the control identifier (tx_datak) are converted into a 10-bit data. After a power on reset, the 8B/10B encoder takes the 10-bit data from the RD- column. Next, the encoder chooses the 10-bit data from the RD+ column to maintain neutral disparity. The running disparity is shown by rx_runningdisp.