E-Tile Transceiver PHY User Guide

ID 683723
Date 4/01/2024
Public
Document Table of Contents

7.12.1.2. Switching from/to refclk[0, 1, 2, 3, 4, 5, 6, 7] to/from refclk[8]

  1. Device configuration defaults the reference clock to refclk_in_A.
  2. Bring up refclk_in_B (refclk[1]), and switch PMA Mux to refclk_in_B (PMA Mux is now working on refclk_in_B (refclk[1]).
    • Make sure the refclk_in_B (refclk[1]) frequency is valid per the data sheet.
    • Write PMA attribute 0x30 = 0x3 to switch the PMA Mux.
  3. Switch Reference Clock Mux (9:1 mux) to refclk[0]; then switch to the target reference clock (PMA Mux is still working on refclk_in_B (refclk[1]).
    • refclk[0] does not have to be bonded out on the board.
  4. Bring up refclk_in_A, and switch PMA Mux to refclk_in_A.
    • Write PMA Attribute 0x30 = 0x0 to switch the PMA Mux.
  5. Perform a PMA Analog Reset.

Switching from/to refclk[0, 1, 2, 3, 4, 5, 6, 7] to/from refclk[8]