UART communication consists of two UART devices that communicate directly with each other. UART is also considered to be “universal” because the parameters including transfer speed and data speed are configurable by the developer. Asynchronous means it doesn’t use a clock signal to synchronize the output bits from the transmitting UART to the sampling bits on the receiving UART. UART, or Universal Asynchronous Receiver/Transmitter, is a hardware communication protocol that uses asynchronous serial communication with configurable speed. We’ll provide some background on USB and UART communication interfaces to get a better idea of how they are similar and different. UART is still used today, but is primarily seen in GPS and Bluetooth modules, Arduino, and other microcontrollers. USB, a serial protocol that also adheres to the RS-232 standard, was introduced as a more advanced and standardized way for devices to communicate through handshaking, device detection, auto speed negotiation, etc. USB, however, has almost completely replaced these outdated cables and connectors that operate using UART communication.

Usb 2 vs usb 3 pinout