The fully integrated 5G QSGMII, 2.5G/1.25G SGMII and 1000BASE-X Physical Coding Sublayer (PCS-X) and Media Access Controller (MAC) core for Ethernet applications is complaint with IEEE 802.3 standard and QSGMII and SGMII specifications. The interface to the PMA supports a single channel Tri mode bi-directional, serial interface. The PCS sublayer supports 8B10B encoding (QSGMII/SGMII/1000BASE-X). This Tri-Mode Core is configurable through software register.