JAJSEY1C April 2019 – March 2022 ADC12DJ5200RF
The first step in initializing the JESD204C link, after the LMFC is deterministically reset by SYSREF, is for the receiver to find the boundaries of the encoded 10-bit characters sent across each SerDes lane. This process is called code group synchronization (CGS). The receiver first asserts the SYNC signal (set to logic '0') when ready to initialize the link. The transmitter responds to the request by sending a stream of K28.5 comma characters. The receiver aligns its character clock to the K28.5 character sequence and CGS is achieved after successfully receiving four consecutive K28.5 characters. The receiver deasserts SYNC (set to logic '1') on the next LMFC edge after CGS is achieved and waits for the transmitter to start the initial lane alignment sequence (ILAS).