It is possible to have multiple software serial ports with a speed up to 115200 bps, but in the Nano Every board the maximum speed is limited to 9600 bps. The SoftwareSerial library has been developed to allow serial communication on other digital pins of the Arduino, using software to replicate the functionality (hence the name "SoftwareSerial").
The Arduino hardware has built-in support for UART communication on pins 0 and 1. If you want to learn more about the UART protocol and how it works, you can check this link. This is not the case for the Nano or MKR families, since these boards have two separate channels, using Serial for the communication with the computer and Serial1 for the communication with any other device trough UART. In some older boards, TX and RX pins are used for communication with the computer, which means connecting anything to these pins can interfere with that communication, including causing failed uploads to the board. UART is the communication protocol we use to communicate from the computer to the board through the USB cable. In the serial port context, the set baud rate will serve as the maximum number of bits per second to be transferred. The baud rate, is the rate at which information is transferred to a communication channel. These pins are dedicated for that specific purpose, either transmitting or receiving.Īsynchronous means there is no clock signal to synchronize the output bits from the transmitting device going to the receiving end, but the baud rate needs to be the same on both the transmitting and receiving devices. Among the available communication protocols, UART uses only two wires for its transmitting and receiving ends, TX (Transmitter) and RX (Receiver). The UART communication sends data bits one by one, from the least significant to the most significant, framed by start and stop bits so that precise timing is handled by the communication channel.Įmbedded systems, microcontrollers, and computers mostly use UART as a form of device-to-device hardware protocol. It allows an asynchronous serial communication in which the data format and transmission speed are configurable. UART (Universal Asynchronous Receiver-Transmitter) is one of the most used device-to-device communication protocols.
Depending on the commands received by the main Nano Every board, it will turn ON or OFF the built-in LED on different boards. In this example, we will power the Arduino boards through the computer, then we will use the Serial Monitor to send some commands to the main Nano Every board, that will be connected through the UART with others Nano Every boards. If the operating voltage differs between the connected boards, the board with the lower operating voltage could be damaged. Note: This example would work by connecting an Arduino Nano Every board with any other Arduino board, but be mindful that both board must work at the same voltage. To do so, we will connect the boards using a wired communication protocol called UART. In this tutorial we will control the built-in LED on four Arduino Nano Every boards, from a main Arduino Nano Every.
Communicating with Four Boards Through UART