Editing Piezo Speaker

= Description =
A Piezo-Speaker has two connectors and can generate sounds if you apply a frequency. One is + and one is -. If you connect it to the ESP + is connected to the Pin and - to GND.

[[file:Piezo_Speaker_close_up.jpg|x200px]]
[[File:Piezospeaker.PNG|x200px]]
[[File:Piezospeaker1.PNG|x200px]]

= How to connect it electrically =
[[File:Piezzo.PNG|300px]]

= How to control it in MicroPython =
Example code shows how you can play a melody with the speaker. If you want to add higher notes see https://en.wikipedia.org/wiki/Piano_key_frequencies for the needed frequency. The example code was taken and edited from https://micropython-on-esp8266-workshop.readthedocs.io/en/latest/basics.html#beepers.

<syntaxhighlight lang="python" line='line'>
# beeper code from https://micropython-on-esp8266-workshop.readthedocs.io/en/latest/basics.html#beepers
from machine import Pin, PWM
from time import sleep

tempo = 4
#notes and corresponding frequency
tones = {
    'c': 262,
    'd': 294,
    'e': 330,
    'f': 349,
    'g': 392,
    'a': 440,
    'b': 494,
    'C': 523,
    ' ': 0,
}
pin = Pin(27, Pin.OUT)
# Init Beeper without frequency.
beeper = PWM(pin, duty=512)
melody = 'cdefggaaaagaaaagffffeeddddc'
rhythm = [8, 8, 8, 8, 4, 4, 8, 8, 8, 8, 4, 8, 8, 8, 8, 4, 8, 8, 8, 8, 4, 4, 8, 8, 8, 8, 4]

for tone, length in zip(melody, rhythm):
    beeper.freq(tones[tone])
    sleep(tempo/length)
    
beeper.deinit()
</syntaxhighlight>

[[file:Piezo_Speaker.jpg|300px]]
[[file:Piezo_Speaker_close_up.jpg|300px]]
@@ Line 1: / Line 1: @@
 = Description =
 A Piezo-Speaker has two connectors and can generate sounds if you apply a frequency. One is + and one is -. If you connect it to the ESP + is connected to the Pin and - to GND.
-With the speaker in the LMUBox the long Pin is +.
 [[file:Piezo_Speaker_close_up.jpg|x200px]]
@@ Line 11: / Line 10: @@
 = How to control it in MicroPython =
-== Basic code to generate a 500 Hz signal ==
-<syntaxhighlight lang="python" line='line'>
-from machine import Pin
-from time import sleep, sleep_us, sleep_ms
-# assume our speaker is connected to Pin 27, we use it as output
-myLED = Pin(27, Pin.OUT)
-#generate a 500Hz on/off signal
-while True:
-      # this switcheson for 1ms = 1000 us
-      myLED.on()
-      sleep_us(1000)
-      # this switches off for 1 ms = 1000 us
-      myLED.off()
-      sleep_us(1000)
-</syntaxhighlight>
-== Code to play a melody - decoding notes ==
 Example code shows how you can play a melody with the speaker. If you want to add higher notes see https://en.wikipedia.org/wiki/Piano_key_frequencies for the needed frequency. The example code was taken and edited from https://micropython-on-esp8266-workshop.readthedocs.io/en/latest/basics.html#beepers.
-There are some issues with restarting PWM outputs - see [[Known Issues]].
 <syntaxhighlight lang="python" line='line'>
@@ Line 68: / Line 45: @@
 [[file:Piezo_Speaker.jpg|300px]]
 [[file:Piezo_Speaker_close_up.jpg|300px]]
-= Related Tutorial Videos =
-<youtube>HPQMvL1SP_c</youtube>