Program the Serial Read

For this lesson, you’re going to be sending a message from your computer to your Smart Inventor Board. Because you’ll be reading serial data, you will need to program the serial monitor. To start doing that, type the line below within void setup() .

Serial.begin(57600);

This line of code sets the baud rate, which is the amount of bits per second that your Smart Inventor Board will be sending data to your computer.

Serial.begin(BAUD rate);

Flashback to the last lesson! This function creates a high-transfer baud connection between the remote controller and the Smart Inventor Board. A higher baud number means the board will process information faster, but there’s also a higher chance for errors. A lower baud number means the board will process information slower, but there will also be less of a chance for errors.

Baud rates range anywhere from 300 to 250000. Make sure that your baud rate is a number that is found within the drop-down menu in the lower righthand corner of the serial monitor.

Next up and very important: the command that will actually read the data from the serial line. You’ll be using an if statement to do this, and it will be inside void loop ().

if (Serial.available() > 0)

This statement will be true if the serial line detects any message with the same baud rate. You’ll be using your computer to send messages to your Smart Inventor Board, and those will be displayed on the serial monitor.

The next line of code will have your serial monitor doing some printing! Don’t worry — you won’t need a printer with ink and paper for this. Type the line of code below within the if statement’s curly brackets:

{
Serial.println( (char) Serial.read() );
}

This prints, or displays, a new line with whatever characters (char for short) you typed in the serial monitor and clicked send with.

One thing you can do with this is control the Smart Inventor Board with your computer acting as a controller. You could use the char read to activate a command, like driving a motor or turning on an LED.

The final code should look like this:

void setup(){

Serial.begin(57600);

}

void loop(){

    if (Serial.available() > 0)
        {
            Serial.println( (char) Serial.read() );
        }
}

Upload your code to your board, open up the serial monitor, and follow what the video does. The board should repeat whatever you type into the serial monitor!

Want to see the lesson in action? Watch the video!