F-Tile Architecture and PMA and FEC Direct PHY IP User Guide

ID 683872
Date 4/07/2025
Public

Visible to Intel only — GUID: lxi1684258545874

Ixiasoft

Document Table of Contents

A.5.4.3.2. Example 2 : F-Tile FGT 58 Gbps PAM4 and FEC Design

F-Tile FGT 58 Gbps PAM4 and FEC Design with 30 dB Insertion Loss when Auto Adaptation is ON

The details about the designs are described below:
  • The production design uses the following JTAG master id values.
    Table 131.  Production Design JTAG Master ID ValueFor Agilex™ 7 F-Tile ES and production devices with OPNs mentioned in Appendix A.1
    Interface JTAG Master ID
    PMA Avalon® memory-mapped interface 1
    Datapath Avalon® memory-mapped interface 2
    Custom register for error count 3
  • The production design uses logical channel 2 (located at PIN_AG10) to sweep TX equalization parameters.
  • The design uses soft PRBS generator and checker and has a custom register to read out error count.
  • After you program the board, you need to launch ISSP to set source[7] to drive tx_am_gen_2x_ack to 1’b1 and source[5] to 1’b1 to select PRBS31 as shown in the following figure.
    Figure 173. ISSP Settings for Example 2
  1. Observations 1-5 from Example 1 : F-Tile FGT 25 Gbps NRZ design still hold.
  2. Observation 6: For PAM4, only main slice is needed with pre-emphasis off (post_tap_1 = 0, pre_tap_1 = 0, pre_tap_2 = 0) if you use serial internal loopback or electrical loopback module. If insertion loss > 5 dB, you need to turn on the pre-emphasis taps.