Adding the photocell step by step Place the photocell in the breadboard so that one end is in the same row of tie points as the jumper from analog pin A0. The other end should be in the row of tie points below that. The photocell doesn’t have an orientation so don’t worry about placing […]
Read More →Let’s make our projects interactive! We’re going to learn how to make our projects interactive, first by adding a button to turn an LED on and off. Then we will attach a speaker to our Arduino, and control sound and light with our sketch. Finally, we’ll add two more buttons, building a keyboard instrument, on […]
Read More →Digital input: add a button We are ready to get our parts together to start building a circuit with a button. You’ll need these parts: 1 LED 1 220 Ohm resistor (red, red, brown, gold) 1 10K Ohm resistor (brown, black, orange, gold) 1 momentary pushbutton switch Jumper wires Breadboard Arduino Uno USB A-B cable […]
Read More →What’s the code in this sketch? Here’s the code for the ATG5_Button sketch. We’ll step through the details over the next few pages. (We’ve removed the code’s starting comments for the sake of brevity.) Initializing our code and variables ATG5_Button is different from our ATG3_Blink sketch in that there is code that happens before the […]
Read More →Digital input: what is it again? Let’s say that you’re standing outside a friend’s house looking through the window at a light switch. Your friend calls to ask “Is the light switch on?” Your job is to tell the friend “yes the light switch is on” or “no, the light switch is off.” That’s exactly […]
Read More →The ATG5_Button sketch’s loop Now that we understand what digital inputs do, let’s take a look at the ATG5_Button sketch’s loop code. First, let’s look at the line at the top of the code. Exploring the loop In the first line of the ATG5_Button sketch’s loop section (after the void loop() { bit and the […]
Read More →Adding a speaker In this circuit, the button, LED, resistors and jumpers will stay in the same place. We are simply adding a speaker; everything else remains the same. Part to add: 1 speaker As always, before you attach the speaker, make sure your computer is not connected to the Arduino. Attach one end of […]
Read More →Adding a second button We are going to add another button to our circuit so we can play a 2 note tune on our mini-keyboard instrument. We will need another button, another 10 K ohm resistor and more jumpers. Remember to unplug your Arduino from your computer before you add to the circuit. Parts to […]
Read More →Reviewing code concepts We learned a few new, and very important, programming concepts in this chapter. These concepts are critical to writing code in all programming languages, though the details might be a little different than in the Arduino language. Let’s look once more at variables and conditionals. variables A variable is a container in […]
Read More →Off to the races: debugging! What are voltage, current and resistance? How are they related? And why should I care? In this chapter, you will learn about voltage, current and resistance and how they interact with each other. This will help you understand how your circuits are working, and how to make adjustments to them. […]
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