Arria® 10 Transceiver PHY User Guide

ID 683617
Date 4/01/2024
Public
Document Table of Contents

6.12.1. Changing VOD, Pre-emphasis Using Direct Reconfiguration Flow

  1. Perform the necessary steps from steps 1 to 7 in Steps to Perform Dynamic Reconfiguration.
  2. Read from the PMA analog feature address of the channel you want to change. For example, to change pre-emphasis 1st post-tap, read and store the value of address 0x105.
  3. Select a valid value for the feature according to the Arria® 10 register map. For example, a valid setting for pre-emphasis 1st post-tap has a bit encoding of 5'b00001.
  4. Perform a read-modify-write to the address of the PMA analog feature using the valid value. For example, to change the pre-emphasis 1st post-tap, write 5'b00001 to address 0x105.
  5. Perform the necessary steps from steps 9 to 12 in Steps to Perform Dynamic Reconfiguration.
Table 274.  Register Map for PMA Analog Feature
PMA Analog Feature Address Bit Values
Pre-emphasis 1st post-tap 0x105 [4:0]

5'b00000 - 5'b11001

Pre-emphasis 1st post-tap polarity 0x105 [6]

1'b0 = positive

1'b1 = negative

Pre-emphasis 2nd post-tap 0x106 [3:0]

4'b0000 - 4'b1100

Pre-emphasis 2nd post-tap polarity 0x106 [5]

1'b0 = positive

1'b1 = negative

Pre-emphasis 1st pre-tap 0x107 [4:0]

5'b00000 - 5'b10000

Pre-emphasis 1st pre-tap polarity 0x107 [5]

1'b0 = positive

1'b1 = negative

Pre-emphasis 2nd pre-tap 0x108 [2:0]

3'b000 - 3'b111

Pre-emphasis 2nd pre-tap polarity 0x108 [4]

1'b0 = positive

1'b1 = negative

Differential output voltage (VOD) 0x109 [4:0]

5'b00000 - 5'b11111

The PMA analog settings are governed by a set of rules. Not all combinations of VOD and pre-emphasis are valid. Please refer to Arria® 10 Pre-Emphasis and Output Swing Settings for current valid settings. Also, refer to "Analog Parameter Settings" and setup guidelines on post_tap polarity settings.