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67 lines
2.1 KiB
67 lines
2.1 KiB
#!/usr/bin/env python3
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#
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# Copyright 2020 JohSchneider
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#
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# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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#
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AUDIO_DAC_BUFFER_SIZE=256
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AUDIO_DAC_SAMPLE_MAX=4095
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def plot(values):
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for v in values:
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print('0'* int(v * 80/AUDIO_DAC_SAMPLE_MAX))
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def to_lut(values):
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for v in values:
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print(hex(int(v)), end=", ")
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from math import sin, tau, pi
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samples=[]
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def sampleSine():
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for s in range(AUDIO_DAC_BUFFER_SIZE):
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samples.append((sin((s/AUDIO_DAC_BUFFER_SIZE)*tau - pi/2) + 1 )/2* AUDIO_DAC_SAMPLE_MAX)
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def sampleTriangle():
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for s in range(AUDIO_DAC_BUFFER_SIZE):
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if s < AUDIO_DAC_BUFFER_SIZE/2:
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samples.append(s/(AUDIO_DAC_BUFFER_SIZE/2) * AUDIO_DAC_SAMPLE_MAX)
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else:
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samples.append(AUDIO_DAC_SAMPLE_MAX - (s-AUDIO_DAC_BUFFER_SIZE/2)/(AUDIO_DAC_BUFFER_SIZE/2) * AUDIO_DAC_SAMPLE_MAX)
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#compromise between square and triangle wave,
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def sampleTrapezoidal():
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for i in range(AUDIO_DAC_BUFFER_SIZE):
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a=3 #slope/inclination
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if (i < AUDIO_DAC_BUFFER_SIZE/2):
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s = a * (i * AUDIO_DAC_SAMPLE_MAX/(AUDIO_DAC_BUFFER_SIZE/2)) + (1-a)*AUDIO_DAC_SAMPLE_MAX/2
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else:
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i = i - AUDIO_DAC_BUFFER_SIZE/2
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s = AUDIO_DAC_SAMPLE_MAX - a * (i * AUDIO_DAC_SAMPLE_MAX/(AUDIO_DAC_BUFFER_SIZE/2)) - (1-a)*AUDIO_DAC_SAMPLE_MAX/2
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if s < 0:
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s=0
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if s> AUDIO_DAC_SAMPLE_MAX:
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s=AUDIO_DAC_SAMPLE_MAX
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samples.append(s)
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#sampleSine()
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sampleTrapezoidal()
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#print(samples)
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plot(samples)
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to_lut(samples)
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