diodes

• Diodes only allow current to flow in one direction through them.
• Useful for blocking or inverting the negative part of an AC signal.
• An LED or light emitting diode is used to produce light.
• LEDs have an orientation - the longer leg is the positive side (anode) and the shorter is the negative side (cathode)
• Make sure your LED is rated for the current you supply it. In our case a 1/4 or 1/2 watt LED is fine.

circuit diagrams

• Circuit diagrams are a way to depict a circuit using a set of standardized symbols.

Use the following circuit diagram and image to wire up a red LED and make it blink.

The 1k resistor protects the LED from getting to much voltage - if you don’t use one it will burn out quickly.

LEDs have a specific resistor value that can calculated for protection but it involves knowing the voltage drop across the LED and using some formulas - we’ll leave figuring that out for REAL engineers and just use a 1k resistor since it will protect most LEDs.

If everything is wired correctly your LED should now be blinking in sync with the embedded LED on the board.

Modify the Blink code to make your LED blink faster. Compile and upload it to the Arduino.