Comparing the difference between an analog signal and a digital signal.
Using a potentiometer (connected to Analog Pin 0) to dim and brighten three yellow LED's (connected to Digital Pin 6).
Then viewing the signals from Analog Pin 0 and Digital Pin 6 on the oscilloscope. The analog signal can be seen to smoothly rise and fall as the pot is adjusted. The digital signal is only high or low and can be seen pulsing on and off at different rates as the pot is adjusted.
Code used in this sketch can be found at serverwillprovide.com/icuubi/examples/analog_vs_PWM.pde
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