Changes

* ...try it out? What do people in the Arduino forums say?

Continually varying signals, rather than discrete "steps". How does a digital microprocessor create an analog output?

Using Pulse Width Modulation (PWM), setting the duty cycle (and effective voltage) of an on-off signal. This happens 500 times per second (500 Hz).

Open the example ''Examples->Analog->Fading''. The crux of this sketch is the <code>analogWrite</code> function.

Get this working.

Same as the LED, but with a higher current load: your microprocessor can not source enough current to power the bulb. (Or maybe it can, but you probably don't want to test it!) We need to use a power transistor: TIP120. This allows you to control a larger current (the bulb) with a smaller current (digital out from the chip).

[[Image:Lamp_fader.png]] [[Image:BULB.JPG|400px]]

* Basic motor speed control (for a DC motor).

* Same circuit as above, swapping the motor for the lamp.