beaglebone adc iio.py

#!/usr/bin/python3

import iio

iio_context = iio.Context()

class Am335xAdc:
    def __init__( self, vrefp=1.8, vrefm=0.0 ):
        self.vrefp = vrefp
        self.vrefm = vrefm
        self._device = iio_context.find_device('TI-am335x-adc.0.auto')
        if self._device is None:
            raise RuntimeError("ADC not enabled");
        self._channels = []
        self._raw = []
        for i in range(8):
            ch = self._device.find_channel( f'voltage{i}' )
            self._channels.append( ch )
            if ch is not None:
                ch = ch.attrs['raw']
            self._raw.append( ch )

    # output range 0 .. 4095
    def raw( self, ch ):
        return int( self._raw[ ch ].value )

    # output range 0.0 .. 1.0
    def value( self, ch ):
        return self.raw( ch ) / 4095

    # output range vrefm .. vrefp
    def voltage( self, ch ):
        return self.value( ch ) * ( self.vrefp - self.vrefm ) + self.vrefm

adc = Am335xAdc()

for ch in range(7):
    v = adc.voltage( ch )
    print( f'ain{ch} = {v:.2f}V' )