function init()
   adc.setup(adc.ADC1, 0, adc.ATTEN_11db)
   adc.setwidth(adc.ADC1, 12)
end




function read(ch)
   adc.setwidth(adc.ADC1, 12)
   read = adc.read(adc.ADC1, ch)
end



function readall()
   for i=0, 8 do
      print("ADC1 read ch", i, "returned:", read(i));
   end
end