The 800G High Speed Ethernet PCS IP core implements the physical coding sublayer (PCS) of the Draft Standard for Ethernet, Amendment: Media Access Control Parameters for 800 Gb/s and Physical Layers and Management Parameters for 400 Gb/s and 800 Gb/s Operation (IEEE P802.3df/D2.0, February 17, 2023) and the Ethernet Technology Consortium 800G Specification (Revision 1.1).