Burglar alarm
Workshop challenge
The challenge we have set for you is to create a computer controlled burglar alarm.
Alam Specification
The alarm must have an on/off switch so that it can be deactivated.
If activated, the alarm is triggered by the burglar standing on a pressure sensor.
Once triggered, the alarm must sound and continue to sound until it has been reset by the homeowner either by pressing a secret button or by entering a four digit pin number.
When reset the alarm will fall silent and the message ‘alarm reset’ will be displayed.
Pressure Pad
The pressure pad burglar sensor is a simple switch which is operated when a burglar steps on it.
The pressure of the burglar's weight pushes two foil contacts together. This completes the circuit, giving an input through the wires to pin 0 and the 6V pin.
The wires are connected to the micro:bit with micro:pegs.
You have been provided with some instructions and the materials to make a pressure pad.
Carefully follow the instructions and then connect your pressure pad to your micro:bit.
Alarm
The micro:bit turns on pin2, the buzzer output which is the alarm.
The micro:bit is programmed to stay on even when the burglar moves their foot.
Reset
The alarm is reset by pressing buttons A and B on the micro:bit.
Burglar alarm code
