UART (Universal Asynchronous Receiver/Transmitter)

The Universal Asynchronous Receiver/Transmitter (UART) is an integrated circuit or module that facilitates asynchronous serial communication by converting parallel data from a CPU into a serial bit stream for transmission, and vice versa for reception. It operates without a shared clock signal, using start and stop bits to frame data packets, making it fundamental for point-to-point communication in industrial automation, embedded systems, and legacy equipment interfaces.

UART works by transmitting data as a series of bits over a single wire, with each character framed by a start bit (logic low), data bits (typically 5-9 bits), optional parity bit for error checking, and stop bits (logic high). The receiver samples the data line at a predefined baud rate to synchronize and decode the incoming stream, relying on timing rather than a clock signal. It handles flow control via hardware signals like RTS/CTS or software methods to prevent data loss.