1.7 Piggy Bank

In this project we will use Speed sensor module, Raspberry Pi and Scratch to make a Piggy Bank.

Place a piece of paper in the middle of the Speed sensor module and you will see a coin fall into the Piggy Bank on the stage.

../_images/1.7_header.png

Build the Circuit

../_images/1.7_fritzing.png

Load the Code and See What Happens

Load the code file (1.7_piggy_bank.sb3) to Scratch 3.

The 2 terminals in the middle of the speed sensor, one is to send light, one is to receive light; if you put a piece of paper in the middle to isolate the light transmission, thus the speed sensor will output a high level. At this point Scratch receives the high level, then switch the costumes of the sprite and you will see a coin fall into the Piggy Bank on the stage.

Tips on Sprite

Select Sprite1 and click Costumes in the top left corner; upload piggybank1.png, piggybank2.png and piggybank3.png from the home/pi/raphael-kit/scratch/picture path via the Upload Costume button; delete the default 2 costumes, and rename the sprite to piggybank.

../_images/1.7_photoInterrupter1.png

Tips on Codes

../_images/1.7_code2.png

When pin17 is low (no coins are put in), switch the sprite’s costume to piggybank1.

../_images/1.7_code3.png

When pin17 is high (a coin is put in), switch the sprite’s costume to piggybank2, and after 0.5s switch to piggybank3, so that we can see a coin falling into the Piggy Bank on the stage.