In UltraScale+ devices supporting the 100G Ethernet RS-FEC Hard block, a Hard FEC option can be selected when using a fixed line rate of either 24,330.24, 12,165.12, 10,137.6, or 8,110.08 Mb/s.
Up to four CPRI IP lanes can be connected to the same Hard RS-FEC receiver. All four CPRI lanes must run at the same line rate.
If the CPRI core is configured with shared logic in the core, three interfaces are provided for external CPRI cores to connect to the Hard RS-FEC block. The port list is shown in Table 1.
If the CPRI core is configured with shared logic in the example design, a single interface is provided to connect to the host CPRI core which has the Hard RS-FEC block. The port list is shown in Table 2.
An example with four CPRI cores sharing the Hard FEC block is shown in the following figure. The Hard RS-FEC block is described in the Hard RS-FEC Receiver section.