This article mainly discusses the wireless data transmission based on microcontroller in the wireless field parameter monitoring system. The system uses Microchip’s PICl6F876 microcontroller as the MCU to control the A/D conversion of industrial instrument data and data wireless reception and transmission; through RS-232 serial The interface communicates with the computer and transmits data to the database of the control center, which can serve as a reference for future wireless data transmission designs based on microcontrollers.
With the increasing demand for mobile communications and remote data collection, coupled with the increasing cost of wired transmission, people are gradually realizing the necessity of wireless transmission in many detection fields. In the past few years, great progress has been made in the field of wireless communications, including advances in digital circuit and radio frequency circuit manufacturing processes, low-power circuits, high-energy batteries, and the adoption of microelectronics technology. Developments in many of the above aspects have made mobile communication equipment more flexible, economical and reliable. Like the above-mentioned technologies, the development of digital communication technology and digital modulation technology also plays a big role. They make wireless communication networks develop in a more economical and easier to operate direction [1]. Therefore, if we can have a good understanding of the basic principles of wireless communication and the characteristics of these technologies, we can better understand and complete wireless collection of industrial field data. This article mainly discusses related issues in wireless data transmission of microcontrollers.
We develop wireless communication modules, mainly monitoring the display of industrial instruments. The system regularly sends and receives detection data from industrial field instruments, and staff receive the detection data in the monitoring room and monitor the parameters of the industrial site. In terms of system performance indicators, the main components of the monitoring system are: pulse acquisition subsystem on the field instrument side, analog radio frequency processing subsystem, digital part processing subsystem, and host computer monitoring and processing software subsystem. Among them, the digital processing subsystem is the focus of this article’s research. Combined with the functions of the digital processing subsystem, the functions of the classification module are as follows.
The microcontroller PIC16F876 produced by the American Microchip Company is the core of the digital processing subsystem. Mainly processes the detected 4~20mA analog signal. When processing and sending data, the microcontroller is in working state; when no data is sent, the microcontroller is in sleep state to reduce power consumption. At the same time, since the monitoring point circuit is intended to be powered by a battery, a backup power supply must be configured to ensure reliable operation of the system. When the main power supply and the backup power supply are switched, the alarm circuit generates a set signal, starts the switching alarm signal, and notifies the monitoring center to replace the main power supply. The power alarm circuit is also responsible for monitoring the microcontroller. Once the microcontroller is in an unknown state, such as the program “running away” or entering an infinite loop, it will forcefully reset the system. The serial communication interface adopts the nine-pin 232 interface and is mainly responsible for communication with the central station PC host.
Keywords: wireless data transmission