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.
Video Reference: https://youtu.be/jw9_wlNIiHw
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.