2.7 Tumbler

Now we use a tilt switch to control tumbler on the stage, so that the switch tilted, tumbler also tilted.

../_images/8_tumbler.png

You Will Learn

  • How the tilt switch works

  • [if then else] block

  • Adding external sprite

Build the circuit

The tilt switch used here is a ball with a metal ball inside. When it is upright, the 2 pins are connected together, and when it is tilted, they are separate.

Build the circuit according to the following diagram:

  • Connect one pin of the tilt switch to pin 12, which is connected to a pull-down resistor and a 0.1uF (104) capacitor (used to eliminate jitter and output a stable level when the tilt switch is operating).

  • Connect the other end of the resistor and capacitor to GND and the other pin of the tilt switch to 5V.

../_images/tilt_circuit.png

Programming

1. Customize the sprite

Select the Tobi sprite and go to the Costumes page. Select the icon in the bottom left corner and then select Upload Costume.

../_images/8_upload.png

Then open tumbler1.png and tumbler2.png in the sunfounder_vincent_kit_for_arduino\scratch\picture path and make sure you have downloaded the relevant material from github.

../_images/8_add_tumbler.png

Remove the Tobi sprite related costume and change the name to Tumbler. Now that we have customized a new sprite Tumbler, we start scripting it.

../_images/8_rename.png

2. Tilt the switch

If the value of pin12 is read as 0 (the switch is tilted), switch the sprite costume to tumbler2, which is also in the tilted state. Otherwise, switch the sprite costume to tumbler1, upright.

  • [if then else]: The block checks its boolean condition; if the condition is true, the code held inside the first C (space) will activate; if the if the condition is false, the code inside the second C will activate.

  • [=]: The block is used to compare the equality of the values on the 2 sides of the equal sign, from the Operators platette.

../_images/8_script.png