General

Variables are placeholders for numbers, letters and character strings. This means that a variable does not have to remain the same over the entire course of the program. This is especially useful if you want to use a certain information at different places in the program.

Variables can be defined using the ‘set item to’ block.

In the drop-down menu of the block, you can rename the variable and create a new variable.

Example

After a soccer game, you want to store in a variable how many goals were scored. This variable is then shown on the display

In order to extend the simple example a little, it should now be possible to add points live. For every goal you score, you have to press the built-in button on the MCU once.

Data types

Depending on what is stored in a variable you should define the correct data type. You define the data type with the help of the ‘as character’ block. This block is attached to a ‘set item to’ block. Afterwards the value to be stored is inserted in the free block section and the data type is selected in the drop down menu.

In Blockly there are the following data types:

Characters: For single text characters

Text: For whole words or sentences

Boolean: For values that are either true or false (or 1 or 0)

Short number: for single digit numbers

Number: For whole numbers from -32,768 to 32,767

Large number: For large numbers from -2,147,483,648 to 2,147,483,647

Decimal: For decimal numbers