circuitpython/docs/esp8266/tutorial/adc.rst

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2016-05-02 20:39:04 -04:00
Analog to Digital Conversion
============================
The ESP8266 has a single pin (separate to the GPIO pins) which can be used to
read analog voltages and convert them to a digital value. You can construct
such an ADC pin object using::
>>> import machine
>>> adc = machine.ADC(0)
Then read its value with::
>>> adc.read()
58
The values returned from the ``read()`` function are between 0 (for 0.0 volts)
and 1024 (for 1.0 volts). Please note that this input can only tolerate a
maximum of 1.0 volts and you must use a voltage divider circuit to measure
larger voltages.