ESP32 integrates two 12-bit SAR (Successive Approximation Register) ADCs (Analog to Digital Converters) and supports measurements on 18 channels (analog enabled pins)
ESP32 DAC output voltage range is 0-Vdd (3.3 V), the resolution is 8-bits
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Function
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machine.ADC(pin [,unit=1])
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|**Description:**
| Create the adc instance object
|**Parament:**
| **pin:** pin argument defines the gpio which will will be used as adc input
| **unit:** Optional unit argument select ESP32 ADC unit for this instance. Values 1 (ADC1, default) or 2 (ADC2) can be selected