PWM output by using <code>analogWriteRange(new_range);</code></p>
   <p>The frequency can be changed by using <code>analogWriteFreq(new_frequency);</code>. <code>new_frequency</code> should be between 100 and 1000Hz.</p>
   <h3>Analog input</h3>
   <p>Just like on an Arduino, you can use <code>analogRead(A0)</code> to get the analog voltage on the analog input. (0 = 0V, 1023 = 1.0V).</p>
   <p>The ESP can also use the ADC to measure the supply voltage (V<sub>CC</sub>). To do this, include <code>ADC_MODE(ADC