13. Case 12: The Burglar Alarm in Shops

13.1. Introduction


  • After installing the bulglar alarm device in shops, program to send alarms if someone breaks into the shops.

13.2. Function

  • Detect the magnet from the magnetic(compass) function on the micro:bit, if the magnet goes far from the micro:bit, program to send alarms and light on the LED.

13.4. Picture


../../_images/microbit-Smart-City-Kit-case-01-02.png

13.5. Hardware Connection


Connect the red led to P1 port on IoT:bit.

../../_images/microbit-Smart-City-Kit-case-12-03.png

13.6. Software Program


Click “Advanced” in the MakeCode drawer to see more choices.

../../_images/microbit-Smart-City-Kit-case-01-04.png

For programming, we need to add a package: click “Extensions” at the bottom of the MakeCode drawer and search with “iot-environment-kit” in the dialogue box to download it.

../../_images/microbit-Smart-City-Kit-case-01-05.png

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.

13.7. Program


Detect the magnetic intensity in the current field, if the returned value is below the threhold, program to send alarms and flash on the led.

../../_images/microbit-Smart-City-Kit-case-12-07.png

Link: https://makecode.microbit.org/_0fiexRbyoKpE

13.8. Result


  • If someone breaks into the shop, the device sends alarms and the led keeps flashing.