L- and H-Tile Transceiver PHY User Guide

ID 683621
Date 1/30/2024
Public
Document Table of Contents

A.4.4. Loopback

The PMA supports serial, pre-CDR reverse serial and post-CDR reverse serial loopback paths.
Name Address Type Attribute Name Encodings
Reverse Serial Loopback Path

0x144[1]

0x132[5:4]

read-write reverse_serial_loopback

Sets transceiver diagnostic (pre-CDR) or post-CDR reverse loopback mode

Encodings {0x11D[0], 0x132[5:4], 0x137[7], 0x144[1], 0x142[4]} :

6'b000000 - Disable reverse serial loopback

6'b100101 - Enable pre-CDR reverse serial loopback

6'b001010 - Enable post-CDR reverse serial loopback

0x137[7]

read-write diag_loopback_enable

0x144[1]

0x142[4]

0x11D[0]

read-write loopback_mode