Buzzer (RTTTL)

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Introduction

RTTTL (Ring Tone [Text] Transfer Language) was developed by Nokia to play more "easy on the ear" melodies as ringtones for mobile phones. The tunes over all characteristics are created by using three different commands:

  • d - duration
  • o - octave
  • b - tempo (beat)

After that the actual tune is then created using standard notes (a, b, c, d, e, f, and g), before the note the duration is set, after the note the octave ("-" can also be used) is set:

<duration><note><octave>

To compose a jingle you separate the notes with a comma.

Hardware

You can use a buzzer, a speaker or a piezo element to play tones.

Buzzer.jpg Small speaker.jpg Piezo element.jpg

The wiring is pretty simple, for the buzzer:

GPIO -> I/O  on buzzer board
3.3V -> VCC on buzzer board
GND -> GND on buzzer board


For speaker and piezo element:

GPIO -> Positive (red) on speaker/piezo 
GND -> Negative (black) on speker/piezo

ESP Easy

No device is needed, generally you use rules to activate different notifications, or you send commands to activate them. Below you find more information on how to do this.

Melodies and ringtones

From ESP Easy v2.0.0 its possible to play melodies via [RTTTL] (don't forget to remove the spaces):

http://<ESP IP address>/control?cmd=rtttl,14:d=8,o=5,b=180,c6,b,c6,p,g,g-,p,f,b,c6,p,d6,p,g,p,c6,b,c6,p,d6,p,f,g,g-,4p,g,f,4d-

This plays a melody on pin 14.

You can also use these from rules. We use it to let our alarm system give feedback to the user via a piezo speaker.

To make a boot-sound on startup, create a rule like this:

 On System#Boot do 
   rtttl,14:d=10,o=6,b=180,c,e,g
 endon

A place to find more tunes, all saved as txt files.

Tones

Besides RTTTL it's also possible to play a single tone on a pin, via a buzzer, speaker or piezo element:

http://<ESP IP address>/control?cmd=tone,14,1300,200

Plays a 1300 hz tone for 200 ms on gpio-14h

Commands

Command GPIO Value Extra information
tone,<gpio>,<value> 12...16 20...13000 Generally you should use GPIO 12...16 since these generally aren't used. The tone range (in Hz) is only recommended use, you could try tones outside this range.
rtttl,<gpio>,<value> 12...16 d=<duration>,o=<octave>,b=<tempo>,<notes...> Generally you should use GPIO 12...16 since these generally aren't used.