Advanced Lesson 6 Quiz Buzzer System

Share for us


In this lesson, we will apply the remote control function we learned in the fifth lesson of the basics to create a four-person responder. You can write the name of you and your friends in the blank space of the cardboard to simulate the scene of quiz.



Since we use the buttons on the APP, we only need to connect four LEDs and current- limiting resistors to D0~D3.

Programming Steps

Step 1

After creating the project, click Create variable button to create 5 variables: led1, led2, led3, led4 and flag.

Step 2

Initialize the LEDs to output. Then initialize flag to 1. Set the initial state of all lights to off.

Step 3

In this case, we use the buttons in the APP. Click the Remote Control button on the left panel to enter the Remote Control page.

Step 4

Drag 5 buttons from the left column to the right area.

Step 5

Drag the read from the remote block into the Forever block to continuously read the values of 5 buttons on the Remote Control page.

Step 6

Add an if do block and and block to Forever to create judgment conditions.

Step 7

Drag 2 Comparison Operator ( = ) blocks from the Logic category to the and block. Then create judgement conditions as follows.

Step 8

In do, set the value of led1 to 1, which represents the light is on. And assign the value of flag to 0 so that when other buttons are pressed, the corresponding lights will not light up again.

Step 9

Long press the if do block then click the Duplicate button to copy 3 same combined blocks.

Step 10

Change the Button A to B, C and D, then change the led1 to led2, led3 and led4.

Step 11

Add another if do block at the bottom followed by a Comparison Operator ( = ) block used to judge the state of the reset button( button E).

Step 12

In the Comparison Operator ( = ) block, the Button E get value block and the number 0 block are placed, which means that if the button E is equal to 1, the reset button is pressed.

Step 13

Place the set flag to block and set pin D0 off block in do. Assign the value of flag to 1 and turn off all lights.

Step 14

Save the project and flash it into the Raspberry Pi (refer to lesson 0 for details). Then you can simulate a nervous answering scene with your friends!

Fold Cardboard

Step 1

Get the matching cardboard of this lesson.

Step 2

Based on the creases, fold the cardboard into the cube as shown.

Step 3

Build the circuit as follows. Please do NOT change the position of components optionally when building circuits, in case the card cannot be installed.

Step 4

Get the cube of cardboard mounted on the circuit as shown.