Time-triggered communication with UARTs

The simple UART (Universal Asynchronous Receiver and Transmitter) encoding is used in two novel fieldbus protocols for real-time systems, the Local Interconnect Network (LIN) and the Time-Triggered Protocol for SAE class A applications (TTPIA). These protocols use a time-triggered communication schedule to achieve a predictable timing behavior The employment of standard components like a standard UART reduces costs, but the issues of clock drift, send jitter and the adjustability of the send frequency have to be considered.