Universal Synchronous Asynchronous Receiver Transmitter (USART)

Is a hardware communication device that extends Universal Asynchronous Receiver Transmitter (UART) with the option to work in synchronous mode.

Asynchronous Mode

When USART works in asynchronous mode it works identically to Universal Asynchronous Receiver Transmitter (UART).

Synchronous Mode

• A clock signal is transmitted alongside the data
• The clock line coordinates when the receiver samples the data
• No start/stop bits are needed (making transfers more efficient)
• The transmitter typically provides the clock signal