Merge pull request #533 from papahabla/patch-1

Update CircuitPython_I2S_Tone.py

Author: kattni

Adafruit_MAX98357/CircuitPython_I2S_Tone.py

@@ -5,20 +5,22 @@
 import board
 import audiobusio
 
-tone_volume = 0.1  # Increase this to increase the volume of the tone.
+sample_rate = 8000
+tone_volume = .1  # Increase or decrease this to adjust the volume of the tone.
 frequency = 440  # Set this to the Hz of the tone you want to generate.
-length = 8000 // frequency
+length = sample_rate // frequency  # One freqency period
 sine_wave = array.array("H", [0] * length)
 for i in range(length):
-    sine_wave[i] = int((1 + math.sin(math.pi * 2 * i / 18)) * tone_volume * (2 ** 15))
+    sine_wave[i] = int((math.sin(math.pi * 2 * frequency * i / sample_rate) *
+                        tone_volume + 1) * (2 ** 15 - 1))
 
 # For Feather M0 Express, ItsyBitsy M0 Express, Metro M0 Express
 audio = audiobusio.I2SOut(board.D1, board.D0, board.D9)
 # For Feather M4 Express
 # audio = audiobusio.I2SOut(board.D1, board.D10, board.D11)
 # For Metro M4 Express
 # audio = audiobusio.I2SOut(board.D3, board.D9, board.D8)
-sine_wave_sample = audioio.RawSample(sine_wave)
+sine_wave_sample = audioio.RawSample(sine_wave, sample_rate=sample_rate)
 
 while True:
     audio.play(sine_wave_sample, loop=True)