Air Quality Monitoring and Alarm System Based on 51 Microcontroller with LCD1602 Display (Proteus Simulation + Program + Design Report + Schematic + Explanation Video)

Simulation software: Proteus 7.8 and above

Compiler: Keil 4 / Keil 5

Programming Language: C

Design Number: S0085

Design of Air Quality Alarm System Based on 51 Microcontroller

1. LCD1602 displays the air quality alarm values and the detected air quality;

2. Can adjust the air quality alarm value through buttons;

3. When the air quality is below the alarm value, the green indicator light is on.

When the air quality exceeds the threshold, the buzzer alarms, and the red indicator light is on;

4. Collect the voltage change of the air quality sensor MQ-135 using ADC0832 with a potentiometer.

Note that the 51 microcontroller chip in the simulation is compatible; AT89C51 and AT89C52 are specific models of the 51 microcontroller, and the core is the same. In the same schematic, whether it’s STC or AT, the pin functions are the same, the programs are compatible, and the chips can be replaced with STC89C52/STC89C51/AT89C52/AT89C51 and other 51 microcontroller chips.

[Tencent Document] S0085 Cloud Disk Link

https://docs.qq.com/doc/DS0lKdWJsRnhYT0p0

The following is a display of the design materials:

The explanation video includes simulation operation explanation and code explanation.

With the increasing severity of environmental issues, global attention to air quality has reached unprecedented heights. The popularity of air quality monitoring devices in daily life and their application in industrial production processes have become increasingly important. They not only provide real-time and accurate air quality data to help people understand the current environmental situation but also provide strong data support for environmental protection decisions, pollution prevention, and optimization of work and living environments. Therefore, designing and implementing a high-performance, intelligent, and user-friendly air quality alarm system has become an important topic in technological development and environmental protection.

This course design project is based on this background, selecting the classic 51 series microcontroller as the core controller and simulating implementation with the powerful Proteus simulation platform. The intelligent air quality alarm system has multiple functions such as real-time monitoring of air quality parameters, setting and adjusting alarm thresholds, and implementing alarm prompts, fully reflecting the flexibility and practicality of embedded technology in real applications.

The differences between Proteus simulation and physical works:

1. Operating Environment: Proteus simulation runs on a computer, while the physical device runs on a hardware circuit board.

2. Debugging Method: In Proteus simulation, single-step debugging and observing variable value changes can be easily performed, while in physical devices, debugging must be done through a debugger or serial output.

3. Circuit Connection Method: In Proteus simulation, circuit connection modifications can be made through software settings, while in physical devices, modifications must be made through hardware circuit boards and connecting wires.

4. Operating Speed: Proteus simulation is usually faster than physical devices because simulation runs on a computer, while physical devices must consider physical limitations and device response times.

5. Function Implementation: In Proteus simulation, different functions can be implemented through software settings, while in physical devices, implementation must be based on circuit design and device performance.