☆ Hardware Design Components: STC89C52 Microcontroller + GSM SMS Module + DS18B20 Temperature Sensor + MQ2 Smoke Sensor + HC-SR501 Human Motion Sensor + ADC0832 Analog-to-Digital Converter Chip + LCD1602 Liquid Crystal Display + AT24C02 Storage Chip + Buzzer + LED Light + Button.
1. The STC89C52 microcontroller is used as the control core, updating the display in real-time on the LCD1602 to show temperature, smoke, and theft status.
2. Fire Alarm: The system uses the DS18B20 temperature sensor to collect temperature data in real-time and the MQ2 smoke sensor to monitor smoke levels. A dual detection mechanism provides fire warning; if any data is abnormal, the system will activate a red light, sound the buzzer, and send a fire alarm SMS to the reserved phone number.
3. Theft Alarm: When the theft protection feature is activated, the system uses the human motion sensor to monitor if someone approaches. Upon detection, a yellow light will activate, the buzzer will sound, and a theft alarm SMS will be sent to the reserved phone number.
4. Limit Setting: Users can enter settings for temperature and smoke alarm thresholds using the button, and the configured alarm thresholds are stored in the AT24C02 for power-off retention.
5. Theft Switch: Users can activate or deactivate the theft protection feature via button or SMS.