20 lines
600 B
ReStructuredText
20 lines
600 B
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Analog to Digital Conversion
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============================
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The ESP8266 has a single pin (separate to the GPIO pins) which can be used to
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read analog voltages and convert them to a digital value. You can construct
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such an ADC pin object using::
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>>> import machine
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>>> adc = machine.ADC(0)
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Then read its value with::
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>>> adc.read()
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58
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The values returned from the ``read()`` function are between 0 (for 0.0 volts)
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and 1024 (for 1.0 volts). Please note that this input can only tolerate a
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maximum of 1.0 volts and you must use a voltage divider circuit to measure
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larger voltages.
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