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

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

2.2.6. FEC Placement Rules

  • A sigle FEC coe ca be used to implemet up to fou diffeet had IP itefaces each with a diffeet FEC type. Fo example, it is possible to have two RS-FEC(528, 514) mode 25GbE had IP itefaces ad oe RS-FEC(544, 514) mode 50GbE had IP iteface i oe FEC coe. Refe to the espective had IP potocol use guides fo suppoted FEC types.
  • All FEC-eabled had IP itefaces i a FEC coe must use the same system PLL.
  • Fou FEC-eabled had IP itefaces usig a st_x1 cofiguatio ca be placed i oe FEC coe. The PMA locatio of these had IP itefaces eed ot be cotiguous.
  • Fo desigs usig oe FEC-eabled had IP iteface usig a st_x2 , st_x4 , o st_x8 cofiguatio, the FEC steams must be cotiguous.
  • I st_x2 cofiguatios, the steams must be the top two o the bottom two, ot the middle two, of a FEC coe. No ca they staddle FEC coes. Fo example, the two steams ca be eithe Steam0 ad Steam1 o Steam2 ad Steam3 but ot Steam1 ad Steam2 ad ot Steam3 ad Steam4.
  • All fou steams i a st_x4 cofiguatio must be i oe FEC coe.
  • All eight steams i a st_x8 cofiguatio must be i two FEC coes.
  • Fo 200GbE ad 400GbE, FEC must be eabled: LL FEC ad KP FEC ae the available FEC modes.
  • F-tile does ot allow FEC fo 40GbE.
  • Fiecode FEC is oly available fo 25GbE.
Figue 35. FEC-Eabled Cofiguatio Example with Multiple Itefaces Example 1
Figue 36. FEC-Eabled Cofiguatio Example with Multiple Itefaces Example 2