Value Controlwith Variables

Joe Long

Robofest Student AssistantLawrence Tech Computer Science Major

jl0109@gmail.comApril 12, 2007

Create the variable

Navigate to the ‘Edit’ menu (next to ‘file’) Click on ‘Define Variables’ Click ‘create’ and enter

the variable information

and type. Click ‘Close’

Getting the light value

Open the ‘complete’ block menu ( ) Find a Light Sensor block and drag it onto

the field.

Saving the value to a variable

Find a Variable block and drag it onto the field.

In the block’s options panel, change it’s Action to ‘Write’ and select your created variable from the List.

Make the Data Wires(light value saved to a variable)

Click on the ‘tab’ sticking out of the light block ( ), then click on the back ‘tab’ sticking out of the ‘write’ mode variable block

The wire should look

like this:

Read the variable

Drag another variable block onto the field.

In the options panel, select your variable from the list and set the mode to ‘read’.

The block should look like this

When you are done:

Add 2 to the variable

Find the ‘Math’ block and drag it onto the field.

Draw a data wire from the second variable block to the ‘A’ tab on the math block:

Using the math block

Open the math block’s options panel. Set the Operation to ‘Addition’ You can see that the space for ‘A’ is

grayed out, as it is already used. In the ‘B’ space, type in ‘2’

Convert the answer (number) to text for displaying

Find the Number to Text block

Draw a data wire from the ‘#’ tab of the math block to the ‘#’ tab of the conversion block.

Displaying the value

Find the Display block and put it on the field:

In the display block’s options panel, set the Action to ‘Text’ (the location can also be experimented with)

The block should now look like this:

Displaying the value

Open the display block’s drop down menu (by clicking on the line at the bottom edge of the block)

Connect a data cable from the

output of the converter to the

‘T’ tab of the display block.

Display the data for 5 seconds

Find a Wait block and drag it onto the field:

In the options panel, set the Control to ‘Time’ and input 5.

Complete

Steps:1. Read the light value

2. Save it to a variable

3. Do…. Whatever comes in-between…

4. Read the variable

5. Do any required math

6. Convert the number to text

7. Display the text

8. Wait some time before continuing