JESD204B Intel® FPGA IP User Guide

ID 683442
Date 7/20/2023
Document Table of Contents

4.2.2. RX PHY Layer

The word aligner block identifies the MSB and LSB boundaries of the 10-bit character from the serial bit stream. Manual alignment is set because the /K/ character must be detected in either LSB first or MSB first mode. When the programmed word alignment pattern is detected in the current word boundary, the PCS indicates a valid pattern in the rx_sync_status (mapped as pcs_valid to the IP core). The code synchronization state is detected after the detection of the /K/ character boundary for all lanes.

In a normal operation, whenever synchronization is lost, the JESD204B RX IP core always return back to the CS_INIT state where the word alignment is initiated. For debug purposes, you can bypass this alignment by setting the csr_patternalign_en register to 0.

The 8B/10B decoder decode the data after receiving the data through the serial line. The JESD204B IP core supports transmission order from MSB first as well as LSB first.

The PHY layer can detect 8B/10B not-in-table (NIT) error and also running disparity error.