45-Formaldehyde concentration detection alarm system based on 51 single chip microcomputer

Specific implementation functions

The system consists of STC89C52 single chip microcomputer + ZE08-CH2O formaldehyde sensor + LCD1602 liquid crystal display + button + buzzer + indicator light + power supply.

Specific functions:

1. The formaldehyde data measured by the formaldehyde sensor is processed by the single chip microcomputer and displayed in real time by LCD1602;

2. The formaldehyde alarm threshold can be set by pressing buttons;

3. When the measured formaldehyde concentration exceeds the alarm threshold, the sound and light alarm will start.

design background

Nowadays, the degree of automation and informatization is getting higher and higher. With the development of society, the progress of science and technology, and the gradual improvement of people's living standards, various automatic control systems that are convenient for life have begun to enter people's lives, and it also marks that the field of automatic control has become a member of the digital age. The automatic door system with single-chip microcomputer as the core is one of them. It is highly practical, fully functional, and technologically advanced, making people believe that this is the result of scientific and technological progress. It also makes people understand that the development of the digital age will change human life and accelerate the development of science and technology. The application field of single-chip microcomputers is becoming more and more extensive, becoming an indispensable part of people's lives.

Currently, the application of single-chip microcomputers has penetrated into every field of our lives, and it is almost difficult to find a field without traces of single-chip microcomputers.

With the development of society, people's living standards are constantly improving. The development of the real estate industry has led to the rapid development of a series of affiliated industries. Consumers' lives have changed from "quantity-oriented" to "quality-oriented", and "safety, health and comfort" have become the core concepts of life.

Decoration has penetrated into our lives, and the decoration materials are also varied. The harmful element formaldehyde emitted from the decoration materials has brought great threats to our lives. At the same time, different concentrations of formaldehyde have different harms to the human body, and people of different ages and physiques have different resistance to formaldehyde. Formaldehyde is a highly toxic substance and ranks second on the priority control list of toxic chemicals in my country. Formaldehyde has been identified by the World Health Organization as a carcinogenic and teratogenic substance.

hardware design

The function of this design is to detect the concentration of formaldehyde and display it on the LCD. When the formaldehyde concentration exceeds the upper limit set by the user, an alarm will be issued. The system block diagram is as follows.

software design

When no interrupt occurs, the display, key processing and over-limit detection programs are executed again; when an interrupt occurs, the interrupt service program is executed.

Schematic

The schematic diagram of this system was designed using Altium Designer19, as shown in the figure.

program

This design uses KEIL5 software to implement program design, as shown in the figure.

Simulation Implementation

This design uses protues8.7 software to implement simulation design, as shown in the figure.