# A conversation between 2 Micro:Bits

We will now play a game against one another, in which we’ll need Micro:Bits.

You will learn:

• • How to program your Micro:Bits so that they can communicate with each other.
• How to program a radio signal.
• How to send a signal by radio.
• How to multiply numbers and variables.

Register before you start the exercise. Click the button below and sign up.

### ORIENTATION

Take a look at the example and consider the following questions:

• What should I do?
• What are the goals?
• What are the expectations?
• What can I already do?
• What do I still have to discover?

### PREPARATION

View the steps under 'Go!'. Then answer the following questions:

• Which steps should I follow?
• Which steps can I follow?
• How much time do I need?
• What tools do I need?

### Go!

Do the steps one by one. Do you not remember how to do it? View the hints or download the solution.

## STEP 1

### Make a message

Before sending something to each other, we will need to produce a message.
We want to send multiple messages. In order to that, we will have to make a variable. We can produce our messages in the variable.

Every time we press the A-button, our variable has to increase by 1. We’ve done this a few times before.

We don’t want to send an infinite amount of messages. We’ll limit the amount to 5 messages. That means our variable will have to stop counting once it’s more than 5.

• If message <=5 then: show message
• If message >=5 then: clear screen, set message to 0

Do you know which blocks you need? Get started.

Our Micro:Bit now shows the numbers from 1 to 5. We can already send these numbers to the other Micro:Bit. But that’s rather BORING.

• Think of 5 fun icons you can send.
• If message = 1 then: show message, ...
• Make the icons appear on your Micro:Bit when you press the B-button.

If you’ve programmed everything correctly, you can make the Micro:Bit show a different number by pressing the A-button. If you press the B-button, it will show the corresponding icon.

## STEP 2

Before we can let our Micro:Bit send out a message, we’ll first have to “configure the radio”. Start by taking a look at the menu: Radio

In order to make two Micro:Bits talk to each other, you have to set the radio on both Micro:Bits to the same group. Run this program “at start-up”. You can pick any number between 0 and 255. There are many channels you can use if you want to send a message.

## STEP 3

### SENDING THE MESSAGE

When we shake our Micro:Bit, it has to send the message.
Take a look at the menu “Radio”. Which block can you use?

## STEP 4

### RECEIVING THE MESSAGE

The only thing we need to do now, is receive the message.
When the Micro:Bit receives the message, it has to show the icon.

Put this code on 2 Micro:Bits and you can send messages.

Good job, you can now secretly message one another. Can you adapt the code so that you can send sentences?

### REFLECT

Look back at the project you just made. Ask yourself the following questions:

• Does the program work as I expected? Why / why not?
• What works well?
• What works less well?
• How can I approach it differently?