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

ID 683872
Date 11/04/2024
Public
Document Table of Contents

3.7.2. Rate Match FIFO

Whe usig the system PLL clockig mode, you must ceate ad istatiate a ate match FIFO i PMA/FEC Diect mode whe the use FPGA coe logic (use clock domai) us at a diffeet fequecy tha system PLL fequecy (system PLL fequecy ÷ 2 whe double width tasfe is eabled). You must ceate ad implemet this ate match FIFO fo the clock domai tasfe fom the use clock domai to the system PLL clock domai.

As the ate match FIFO is ot available i IP catalog, you must ceate the FIFO. Implemet the FIFO by placig a ate-matchig soft FIFO betwee you logic ad the coe fo pacig the data valid sigal. Use this techique wheeve the use FPGA coe logic (use clock domai) us at a diffeet fequecy tha system PLL fequecy (system PLL fequecy ÷ 2 whe double width tasfe is eabled).