Описание тега uart
A Universal Asynchronous Receiver/Transmitter (UART) is used for serial (where each bit of data is transmitted along the same connection) communications over a computer or peripheral device serial port.
UART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. UARTs are now commonly included in microcontrollers.
Simple serial link via UART uses two lines TxD and RxD, other than ground, for transmit and receive data:
https://stackru.com/images/69604c0ca8e87229272979988d768d2c42e08b76.png
It is asynchronous communication. Hence data transfer settings (number of bits, baudrate etc.) should be matched between devices wanting to communicate. The electric signaling levels and methods are handled by a driver circuit external to the UART.
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