E-Tile Transceiver PHY User Guide

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

5. PMA Calibration

The PMA is automatically calibrated when it is first enabled. When dynamically reconfiguring the PMA to a different data rate, you need to recalibrate the PMA. The PMA calibration is run when the PMA is enabled after a PMA analog reset, so you perform a PMA analog reset before requesting calibration. Refer to PMA Attribute Details for information on how to change PMA settings using the Avalon® memory-mapped interface. When referring to the PMA Attribute Codes section of the register map keep the following guidelines in mind:

  • If you change any setting where yes is indicated in the PMA Can be Running While Updating column, ensure that you do not disable the transceiver channel. If you disable the channel, then the transition of disable to enable initiates the calibration and causes bit errors.
  • If you change any setting where no is indicated in the PMA Can be Running While Updating column, follow the following flow chart.

Refer to PMA Attribute Codes for information on which attributes can only be changed when the PMA is disabled.

When the Native PHY's tx_pma_ready/rx_pma_ready outputs assert, calibration is complete.

Figure 74. Enabling PMA Calibration