126.96.36.199.1. Reset Condition for 8B/10B Encoder in GbE, GbE with IEEE 1588v2
After deassertion of tx_digitalreset, the transmitters automatically transmit at least three /K28.5/ comma code groups before transmitting user data on the tx_parallel_data port. This transmission could affect the synchronization state machine behavior at the receiver.
Depending on when you start transmitting the synchronization sequence, there could be an even or odd number of /Dx.y/ code groups transmitted between the last of the three automatically sent /K28.5/ code groups and the first /K28.5/ code group of the synchronization sequence. If there is an even number of /Dx.y/code groups received between these two /K28.5/ code groups, the first /K28.5/ code group of the synchronization sequence begins at an odd code group boundary. The synchronization state machine treats this as an error condition and goes into the loss of synchronization state.