Is Arduino UART or USART further is Arduino Half or Full Duplex

Projects Networking, Protocols, and Devices
1

HI,
I want to know if Arduino uses UART or USART and please confirm whether Arduino is half duplex or full duplex.
Can I simultaneously transmit and receive data using Tx and Rx pins?
Asking about Arduino UNO. give some highlights of others as well

2

There are many different "arduino"s

3

uno

4

The datasheet for the ATMEGA328P used on an UNO calls the hardware serial interface a USART. The first bullet point in the section on the USART is:

  • Full Duplex Operation (Independent Serial Receive and Transmit Registers)

You mention half duplex. That term usually appears when the user is trying to implement an RS485 serial link (maybe for a Modbus protocol based comms link). With an UNO, the hardware serial port is connected to the on board USB-serial hardware so it is best to avoid using pins 0 and 1, especially if you also want to print out diagnostic information.

If you need a second serial port, then the non hardware option for an UNO is to use a software serial port implementation.

Your other option is to upgrade to a MEGA2560 board with 4 hardware serial ports.

5

Or using a Leonardo or Micro if the big footprint of a MEGA is a problem or you don't need the additional features/memory. The USART on Leonardo/Micro is independent of the USB connection an can be used freely. It even has HW Flow control, which the 328P processor doesn't have.