10. Case 09: Invading Detection Device¶
This is an intrusion detection device. When the ultrasonic sensor detects that someone is approaching, it will automatically turn on a red light and alarm through the buzzer on the micro:bit. If the ultrasonic sensor does not detect anyone, it will automatically turn on green light.
10.2. Quick Start¶
Nezha expansion board × 1
micro:bit × 1
LED-green × 1
LED-red × 1
Sonar:bit × 1
RJ11 wires × 3
Connect the sonar:bit to J1, red LED to J2 and green LED to J3 on the Nezha expansion board as the picture shows.
10.3. MakeCode Programming¶
Click “Advanced” in the MakeCode to see more choices.
For programming, we need to add a package: click “Extensions” at the bottom of the MakeCode drawer and search with “PlanetX” in the dialogue box to download it.
Notice: If you met a tip indicating that some codebases would be deleted due to incompatibility, you may continue as the tips say or create a new project in the menu.
Code as below:¶
You may also download it directly below:---
While the sonar:bit detects the object, the red LED lights up and the buzzer alarms.