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changeset 23:a47fafb6e1e5

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Add melody example
author Radomir Dopieralski <sheep-devel@sheep.art.pl>
date Sat, 18 Jun 2016 13:25:24 +0200
parents 379eeec3777a
children 9740ae97a3a9
files basics.rst
diffstat 1 files changed, 30 insertions(+), 3 deletions(-) [+]
line wrap: on
line diff
--- a/basics.rst	Fri Jun 17 12:19:45 2016 +0200
+++ b/basics.rst	Sat Jun 18 13:25:24 2016 +0200
@@ -311,9 +311,36 @@
     time.sleep(0.5)
     beeper.deinit()
 
-Unfortunately, we can't really play any melodies, as the possible frequencies
-currently don't cover the musical notes. We can make noises, and that's pretty
-much it.  We can play music and other sounds, but not with the PWM.
+We can even play melodies! For instance, here's the musical scale::
+
+    from machine import Pin, PWM
+    import time
+
+    tempo = 5
+    tones = {
+        'c': 262,
+        'd': 294,
+        'e': 330,
+        'f': 349,
+        'g': 392,
+        'a': 440,
+        'b': 494,
+        'C': 523,
+        ' ': 0,
+    }
+    beeper = PWM(Pin(2, Pin.OUT))
+    melody = 'cdefgabC'
+    rhythm = [8, 8, 8, 8, 8, 8, 8, 8]
+
+    for tone, length in zip(melody, rhythm):
+        beeper.freq(tones[tone])
+        time.sleep(tempo/length)
+
+Unfortunately, the maximum frequency of PWM is currently 1000Hz, so you can't
+play any notes higher than that.
+
+It's possible to make the sounds louder by using a better speaker and possibly
+an audio amplifier.
 
 
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