clock recovery unit (CRU) Definition
Dedicated circuitry inside the GXB receiver channel of the gigabit transceiver block (GXB) in supported device ( Stratix® IV GT, Stratix®IV GX, and Stratix® IV GT) families. The CRU, used for Clock Data Recovery (CDR), generates a clock based on a reference clock and the incoming serial data to generate a high-speed clock synchronized to the transitions inside the data.