B - Save our Robot!

Having red/green LEDs is a great start to communicating with our robot

What if we want to communicate more than just red or green?

Morse Code allows us to send any letter or number we like, just using a single light or buzzer!

Watch the video to find out more.

It's your turn to try and decode some morse code into words!

See if you can work out the sequence of letters in the video using the decoding card.

Make sure you get this challenge checked off when you know the answer!

Let's write a program that will send the letter S.

In the picture is a program to send 1 dot with the LED. For your wait blocks, we suggest:

100 milliseconds for a dot

1 second for a dash

Extend the program in the picture to send 3 dots, which is an S - your LED module should still be plugged in to A like the last lesson!

Can you work out how to make the S program shorter?

We can use a do _ times loop like we used for moving the robot in a square!

Change your program so it sends Morse Code for an S using a loop.

You might have noticed when you were listening to the code, that between the letters we need longer gaps so you can tell when they start and finish.

A time of 2 seconds works well.

Put your loop that flashes an S inside a do forever loop so it flashes S forever, and add a wait block so there is a gap of seconds between each S.

Let's make a program to get our robot to flash SOS using an LED, in case it has a problem.

Your program should flash the sequence of dots and dashes required for the letters SOS - for bonus points put it in a loop to make it flash SOS forever!

Try to shorten your program using do _ times loops.

If you're a bit stuck, have a look in the picture to see which blocks you will need to use.

Using lights for Morse Code is great for long distances, such as between two ships, but what if you are looking the other way when your robot is in trouble?

Replace your LED module with the buzzer module like in the picture, so your robot buzzes SOS instead.

If you're feeling really clever, put the LED module back into another output and add some more set blocks so it flashes and buzzes the sequence for S.O.S!