Media access control (MAC) to physical coding sublayer (PCS) data rate synchronization circuitry

Abstract

A system includes a MAC layer and a PCS in communication with the MAC layer via a transmit data path. The transmit data path includes a data request signal transmitted from the PCS to the MAC layer and a data valid signal transmitted from the MAC layer to the PCS. A SYNC pipeline of the PCS generates a copy of the data valid signal that has a same timing as the data valid signal. When the data valid signal from the MAC layer to the PCS matches the copy of the data valid signal generated by the PCS, the PCS is in synchronization with the MAC layer. When the data valid signal from the MAC layer to the PCS does not match the copy of the data valid signal, the PCS ignores input data from the MAC layer and generates an idle symbol to a link partner.

CPC Classifications