Using the UART interface to communicate between two Pico boards
In this section, we will discuss the Universal Asynchronous Receiver/Transmitter (UART) interface and its applications. We will be making use of two Pico boards to transmit a message from one Pico to another. The second Pico echoes back the incoming message. Before we jump into the example, let's take a quick look at the UART interface.
The UART interface
The UART interface is a communication protocol using two lines, namely a transmitter and a receiver (shown in the following figure). As the name suggests, the protocol is asynchronous; that is, there is no reference clock signal for the communication. The communication happens at a preset speed known as a baud rate. Typical baud rates include 9600, 19200, 38400, and so on.
The UART interface is used to communicate with sensors such as GPS sensors, dataloggers, and so on. The following figure shows the connection between two devices. The receiver (RX) of...