- 220 Ohm Resistor (The book uses a 270 Ohm resistor. This is the closest I had lying around.)
Time to Complete: 15 minutes
The S.O.S. program is also fairly easy to implement. The project first has you write out the code in a very long-handed fashion. That is: turn light on, wait, turn light off, wait, etc. for the entire S.O.S. process of three dots three dashes, the dots. So in this way, we tell the pin to alternate from going from HIGH (5V) to LOW (0V).
Since the above code is tedious, the book introduces the concept of functions by having the user create a simple flash function that turns on and then off the LED for the number of milliseconds given in the argument. The original code collapses by about a factor of two after implementing the flash function. I have included a short video of the final product.
The next project is a logical extension of this one. The Arduino will be used to translate a string of input text into Morse code LED flashes. This will be slightly more involved since it means that the Morse code alphabet will need to be define in the code, but it should also be very straight-forward.