Application design of elevator control system based on single chip microcomputer

1. Introduction

In the 1990s, countries with advanced electronic and computer technologies have been actively exploring new electronic circuit design methods, and have made radical changes in design methods and tools, achieving great success. In the field of electronic technology design, the application of programmable logic devices (such as CPLD and FPGA) has been widely popularized, and these devices have brought great flexibility to the design of digital systems. These devices can reconstruct their hardware structure and working mode through software programming, making hardware design as convenient and fast as software design. All of this has greatly changed the traditional digital system design methods, design processes and design concepts, and promoted the rapid development of EDA technology.

Elevators are vertical transportation tools that symbolize modern material civilization and are complex transportation equipment that integrates mechatronics. They involve multiple scientific fields such as electronic technology, mechanical engineering, power electronics technology, microcomputer technology, electric traction systems, and civil engineering. As an important equipment for transportation up and down high-rise buildings, more and more mechatronics professionals will participate in elevator technology work. In order to master the structure and control technology of elevators, it is necessary to simulate this huge product that integrates machinery, electricity, and sensors, and use control methods such as PLC, single-chip microcomputer, microcomputer, and inverter to develop multi-functional application software.

The core control chip of the system is the 51 series single-chip microcomputer AT89C52. The rapid development of single-chip microcomputers in various technical fields is related to the characteristics of computer application systems composed of single-chip microcomputers:

The application system composed of single chip has greater reliability.

The system is simple and easy to build, and can conveniently realize system functions.

Since the constructed system is a computer system, many functions are implemented by software, so it is flexible.

This paper designs a practical single-chip elevator controller. According to actual needs, it uses a high-performance AT89C52 single-chip microcomputer and a dedicated display and keyboard control chip, and cooperates with corresponding software to achieve real-time control of the elevator. Its main features are simple circuit structure, strong control function, and high reliability.

2. Hardware circuit design

With the development of society, the use of elevators has become more and more common. It has transitioned from being used only in commercial buildings and hotels to being used in office buildings, residential buildings and other places. The requirements for elevator functions are also constantly increasing, and the control methods are also constantly changing accordingly. For elevator control, the traditional method is to use a relay-contactor control system for control. With the continuous development of technology, the application of microcomputers in elevator control has become increasingly widespread, and now we have entered the era of full microcomputer control. The microcomputer control of elevators mainly has the following forms: ①PLC control; ②single-board computer control; ③single-chip microcomputer control; ④single microcomputer control; ⑤multi-microcomputer control; ⑥artificial intelligence control. With the rapid development of EDA technology, single-chip microcomputers have been widely used in various aspects of electronic design and control.

This design uses an AT89S52 single-chip microcomputer to control the elevator; a digital tube is used to display the current floor of the elevator.

Specific requirements are:

1) Use digital tube to display the current elevator floor;

2) Respond to the earliest request first. If there are requests sent at the same time, respond to the nearest request first.

Main tasks and requirements:

Design an 8-story automatic elevator controller with a request button switch on each floor. When the elevator reaches the requested floor, the corresponding indicator light goes out, the elevator door opens, and the door opening indicator light comes on. It automatically turns off after 5 seconds and continues to run.

The circuit block diagram of this design is shown in Figure 1, and the specific circuit schematic is shown in Figure 2.