This section describes the optional RS-FEC function of the 50G Ethernet subsystem. The RS-FEC option must be specified at the time of generating the subsystem from the IP catalog or ordering the IP core asynchronously.
The RS-FEC block is positioned between the PCS and PMA as illustrated in 40G/50G MAC with PCS/PMA Clocking.
With reference to the following diagram, the RS-FEC core clocks and resets are equivalent to the transceiver signals, with the transceiver resets being active-High.
Figure 1. RFC Block Position