The Sync Field, a byte with the fixed hexadecimal value 0x55, enables devices on a LIN bus to synchronize their clocks with the master node. The value 0x55 represents a binary pattern of alternating 1s and 0s, creating predictable signal transitions (edges).

Here is how this works:

• The LIN commander transmits this alternating pattern.
• The Responder nodes measure the time between these signal transitions to determine the master's precise bit timing.
• The Responder nodes then use this measurement to adjust their baud rate, ensuring they are perfectly synchronized with the Responder’s baud rate.