This is a sample app which fades a LED using PWM.

The LED will start from dark and increases its
brightness gradually for 10 seconds. Then, the
brightness reduces gradually for 10 seconds and
finally the LED becomes dark again. The LED will
repeat this cycle for ever.

Arduino 101 and Quark D2000 CRB
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You will need to connect the LED to ground and PWM0 via
the shield. You may need a current limiting resistor. See
your LED datasheet.