# Getting started ## ~avatar Are you ready to build cool BBC micro:bit programs? Here are some challenges for you. Arrange the blocks in the editor to make real programs that work! ## ~ ### Happy face There are three blocks in the editor (the area to the left). Arrange them to look like this: ```blocks basic.forever(() => { basic.showLeds(` . . . . . . # . # . . . . . . # . . . # . # # # . `) basic.showLeds(` . . . . . . . . . . . . . . . . . . . . . . . . . `) }); ``` When you run this program, you will see a smiley face, then a blank screen, then a smiley again -- it never stops! (That's because of the ``forever`` block.) Click **Compile** to move your program to the BBC micro:bit! ### Happy unhappy face Draw an unhappy face instead of the blank screen. Click on the dots in the second ``show leds`` block until it matches the blocks below. Now you have an **animation** (cartoon) that shows a happy face, then an unhappy one, then a happy one again, forever (or until you turn off your micro:bit)! ```blocks basic.forever(() => { basic.showLeds(` . . . . . . # . # . . . . . . # . . . # . # # # . `) basic.showLeds(` . . . . . . # . # . . . . . . . # # # . # . . . # `) }); ``` Click **Compile** to move your program to the BBC micro:bit! ### Your turn! Pile up more ``show leds`` blocks to create your animation! Create an animation with at least 5 pictures. What does this animation show? ```blocks basic.forever(() => { basic.showLeds(` . . . . . . # . # . . . . . . # . . . # . # # # . `) basic.showLeds(` . . . . . . # . # . . . . . . # # # # # . . . . . `) basic.showLeds(` . . . . . . # . # . . . . . . . # # # . # . . . # `) basic.showLeds(` . . . . . . # . # . . . . . . # # # # # . . . # # `) basic.showLeds(` . . . . . # . # . . . . . . . # . . . # . # # # . `) basic.showLeds(` . . . . . . . # . # . . . . . # . . . # . # # # . `) }); ``` Click **Compile** to move your program to the BBC micro:bit! #### ~hint You can find the ``show leds`` block in the **Basic** part of the editor. #### ~ ### Button A and button B This program will show the word **ANTEATER** on the LED screen when you press button `A`. ```blocks input.onButtonPressed(Button.A, () => { basic.showString("ANTEATER"); }); ``` #### ~hint The ``showString`` block can show letters, numbers, and punctuation on the micro:bit screen. #### ~ Now try to unscramble these blocks in the editor so that the micro:bit shows **BANANA** when you press button `B`. ```shuffle input.onButtonPressed(Button.B, () => { basic.showString("BANANA"); }); ``` #### ~hint You can find the letter `B` by clicking the letter `A` on the ``onButtonPressed`` block. #### ~ Click **Compile** to move your program to the BBC micro:bit! #### Your turn! Can you combine these blocks so your program shows your real name instead of **ANTEATER** when you press `A`, but _your secret agent name_ instead of **BANANA** when you press `B`? ### Shake You can find when someone is shaking the BBC micro:bit by checking its **accelerometer** (it finds whether the micro:bit is speeding up or slowing down). Unscramble these blocks in the editor to show a frownie when someone shakes the micro:bit. (Ouch!) ```shuffle input.onGesture(Gesture.Shake, () => { basic.showLeds(` . . . . . . # . # . . . . . . . # # # . # . . . #`); }); ``` Click **Compile** to move your program to the BBC micro:bit! ### Pins You can also use the pins as buttons. (The pins are the holes in the metal stripe at the bottom of the micro:bit board.) For example, hold the ``GND`` button with one hand and touch the ``0`` pin (called ``P0``) with your other hand to tell the micro:bit you're pressing it. Unscramble the blocks in the editor to show a heart when you touch pin ``P0``. ```shuffle input.onPinPressed(TouchPin.P0, () => { basic.showLeds(` . # . # . # . # . # # . . . # . # . # . . . # . .`); }); ``` Click **Compile** to move your program to the BBC micro:bit! ## ~hint Try this experiment: find a friend and hold hands. Touch the ``GND`` pin while your friend presses the ``P0`` pin. You should see the heart! The electric current is going through your bodies and across your handshake to make it happen! ## ~ ## The amazing coin flipper ### ~avatar avatar Are you trying to choose whether to play soccer or go to the movies instead, or which toppings to have on your pizza? Build a coin flipping machine with the BBC micro:bit to choose for you! ### ~ Here are the blocks to make your coin flipper. When you press button `B`, the coin flipper will show either `H` for heads or `T` for tails on the LED screen. ```blocks input.onButtonPressed(Button.B, () => { if (Math.randomBoolean()) { basic.showString("H"); } else { basic.showString("T"); } }); ``` ### ~hint The ``pick random true or false`` block randomly tells the ``if`` block `true` or `false`. If the ``pick`` block picked `true`, the ``if`` block shows the letter `H`. Otherwise, it shows the letter `T`. That's it! ### ~ ### Keeping score #### ~avatar To keep track out of how many guesses you've won, add these blocks to your coin flipper: #### ~ ```blocks input.onButtonPressed(Button.A, () => { game.addScore(1); }); input.onButtonPressed(Button.AB, () => { basic.showNumber(game.score()); }); ``` These blocks mean that if you press button `A`, you will add `1` to your score, and if you press `A` and `B` together, the micro:bit will show your score. When you're done, your coin flipping program should look like this: ```blocks input.onButtonPressed(Button.B, () => { if (Math.randomBoolean()) { basic.showString("H"); } else { basic.showString("T"); } }); input.onButtonPressed(Button.A, () => { game.addScore(1); }); input.onButtonPressed(Button.AB, () => { basic.showNumber(game.score()); }); ``` Flip until your thumbs get tired! ## Let's play Rock Paper Scissors! ### ~avatar avatar Build a Rock Paper Scissors game with the BBC micro:bit! You can play the game with a friend who has it on a micro:bit. You can also play it with friends who are just using their hands. (The game is built like a coin flipper, but with three choices instead of two.) ### ~ ## Step 1: Getting started We want the micro:bit to choose rock, paper, or scissors when you shake it. Try creating an ``on shake`` block so when you shake the micro:bit, it will run part of a program. Clear up the blocks and add the blocks below. ```blocks input.onGesture(Gesture.Shake, () => { }) ``` Next, when you shake the micro:bit, it should pick a random number from `0` to `2` and store it in the variable `item`. Add a ``set`` block with a variable. Then add a ``pick random`` block, and store the random number in the variable, like this: ```blocks input.onGesture(Gesture.Shake, () => { let item = Math.random(3) }) ``` ### ~hint No one can predict random numbers. That's what makes them great for Rock Paper Scissors! ### ~ Each possible number these blocks can make (`0`, `1`, or `2`) means a different picture. We will show the right picture for that number on the LED screen. ## Step 2: Picking paper Put an ``if`` block after the ``let`` block that checks whether `item` is `0`. Make sure the ``if`` block has an ``else if`` part and an ``else`` part. Next, add a ``show leds`` block that shows a picture of a piece of paper: ```blocks input.onGesture(Gesture.Shake, () => { let item = Math.random(3) if (item == 0) { basic.showLeds(` # # # # # # . . . # # . . . # # . . . # # # # # # `) } else if (false) { } else { } }) ``` ## Step 3: A random rock Now we are going to add a new picture for the micro:bit to show when another random number comes up. Make the ``else if`` part check if the variable `item` is `1`. Then add a ``show leds`` block with a picture of a rock. ```blocks input.onGesture(Gesture.Shake, () => { let item = Math.random(3) if (item == 0) { basic.showLeds(` # # # # # # . . . # # . . . # # . . . # # # # # # `) } else if (item == 1) { basic.showLeds(` . . . . . . # # # . . # # # . . # # # . . . . . . `) } else { } }) ``` ## Step 4: Suddenly scissors Add a ``show leds`` block with a picture of scissors to the ``else`` part: ```blocks input.onGesture(Gesture.Shake, () => { let item = Math.random(3) if (item == 0) { basic.showLeds(` # # # # # # . . . # # . . . # # . . . # # # # # # `) } else if (item == 1) { basic.showLeds(` . . . . . . # # # . . # # # . . # # # . . . . . . `) } else { basic.showLeds(` # # . . # # # . # . . . # . . # # . # . # # . . # `) } }) ``` ### ~hint You don't need to check if `item` is `2` because `2` is the only number left out of `0`, `1`, and `2`. That's why you can use an ``else`` instead of an ``else if``. ### ~ Your game is ready! Click **Compile** to move your program to the BBC micro:bit! Have fun! ## Step 5: Are you the greatest? Here is a way you can make your Rock Paper Scissors game better. When button ``A`` is pressed, the micro:bit will add `1` to your score. Open the ``Game`` drawer, and then add the block ``change score by 1`` to your program, like this: ```blocks input.onButtonPressed(Button.A, () => { game.addScore(1) }) ``` ## Step 6: Prove you're the greatest! After your micro:bit can add `1` to the score, show how many wins you have. ```blocks input.onButtonPressed(Button.A, () => { game.addScore(1) basic.showString("WINS:") basic.showNumber(game.score()) }) ``` ## Step 7: Staying honest Success! Your micro:bit can track wins! But what about losses? Use the ``Game`` drawer to subtract `1` from your score when you press button `B`. Here are all the blocks you will need: ```shuffle input.onButtonPressed(Button.B, () => { game.addScore(-1) basic.showString("LOSSES:") basic.showNumber(game.score()) }) ``` Click **Compile** to move your program to the BBC micro:bit! ## Your turn! How else can you make your game better? Ever hear of [Rock Paper Scissors Spock Lizard](http://www.samkass.com/theories/RPSSL.html)?