![]() Even though we don't need any code in the loop procedure, this procedure still cannot be simply omitted. I implemented everything in the setup procedure, as I want to play the tune only once. A variable declared as const cannot be changed at runtime - it's a constant. You might notice that I used the keyword const in the variable declaration. const int F = 349 const int G = 392 const int A = 440 const int BB = 466 const int C = 523 To make our lives easier we can define variables for each note and assign the corresponding frequency as value. For this we need to translate the notes into a frequency. Now we will have to write code to generate each individual note in the music sample. To control the duration of tones, we will just use the delay procedure. As a result you will only hear some clicking noises. If you want to produce multiple tones right after each other this will cause the first tone to be interrupted by the second one before it was fully played. The problem is, that this won't block but instead measure the duration using the hardware timer. There is also a version of the tone function to which you can pass a duration for the tone as a third argument. Using noTone we can silence the speaker again. Using the tone procedure, we can generate a tone with a given frequency. frequency: Frequency of the tone to generate.In our code we will need the following new functions: You can connect a 220 Ω resistor in series to reduce the loudness. But to be honest to you, a small piezo speaker is annoying enough. The Arduino is able to drive the piezo speaker directly, for real speakers or a big piezo speaker you need an amplifier. This is however not the goal of this tutorial. It has an internal circuit for generating this tone and can be operated with a fixed voltage using a simple digital output. A buzzer only makes one sound with a fixed frequency. Make sure you picked a piezo speaker and not a buzzer. Just connect the piezo speaker to pin 8 of the Arduino. There is not much to say about the circuit. For granted the result won't sound as perfect and harmonic as a piano, but it's fun to play with sounds and maybe you recognize the piece of music I chose. ![]() I chose a small music sample, that we are going to recreate with the Arduino and a piezo speaker. However, we won't be able to use PWM on pins 3 and 11 at the same time, as the Arduino needs to use the same hardware timer for this.Įnough theory, let's get started. An advantage opposed to directly using the PWM hardware is, that we can use any pin and not just PWM capable pins. The signal is generated by toggling a pin with the help of a hardware timer. The technique used is somewhat similar to PWM, but the Arduino implementation does not use the PWM peripheral directly to generate sound. There is a handy procedure called tone available, which allows us to create tones with a specific frequency. For making different sounds we need a signal with adjustable frequency. Last time we looked into PWM which allowed us to change the duty cycle of a fixed frequency signal. Time for some music! In this tutorial we create sounds using a piezo speaker and our Arduino Uno.
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