Study On Intelligent Control And Detection System Of IC Card Gas Meter

With the coming of the information age, technology of integrated circuit card (IC card) has become mature, and safe and reliable control system based on IC card emerges as the times require. The technology of IC card, together with its wide application and its large market, has become a most outstanding representative for economic informationization of our country. Meanwhile, a systematic research on IC intelligent gas meter which can realize self-measure and automatic control has bright future, important scientific significance and huge socioeconomic value. Besides, it is of great importance for solving problems and disadvantages of charge personally. Combined with the developing situation and status quo of IC intelligent gas meter at home and abroad, this paper puts forward a new systematic structure with MCS-51 chip microcomputer as its control core, with IC card as its information carrier and with CPLD as its alarming control module. At the same time, this paper establishes, designs and triturates the detection and control system of IC intelligent gas meters.Meanwhile, software of the detection and control system, along with that of the management system of the uppwe machine, is designed.This paper replaces sampling of single-channel measurement with sampling of two-channel measurement aiming at improving accuracy and sensitivity of the whole detection and control system and replaces peripheral devices of microprocessor with programmable logic devices, which simplify the detection and control system structure and cut the cost. Meanwhile, IP cores, such as serial port communication and LED reading scan are developed with VHDL hardware descriptive language, which relieve the work of microprocessor. As a result, the detection and control system can detect quickly and reliably, which adds the system's expandability and flexibility of upgrading the system.This paper mainly accomplishes the following aspects:1. After a detailed discussion on characteristics of detection and control objects of the IC intelligent gas meter, the gross structure of integrated detection and control systems are designed.2. The chip AT89C4051, which is taken as CPU of the detection and control system, is used to design a detecting system with high resolution, strong real time and accurate measurement. High accurate voltage monitoring chips are used to assure the stability of the system's current supply and valve closure.3. Memorizers and IC interface circuit based on I2C bus are designed. Through the interface, high-speed digital communication is implemented. Meanwhile, read-write devices of IC card with RS-232 interface is designed, and communication of IC card with PC and other devices is realized.4. Hardware circuit design of serial digital receipt, storage and display of received information is realized with CPLD, and corresponding IP core is developed with VHDL language.5. Software concerned in the system is programmed with assemble language. Management system of charge in advance of IC card gas meters is designed to realize charge in advance and gas sale. The system has good man-machine interface, which can store gas users'information into a designed database and can analyze correlative matters according to gas information of customers.