Laboratory Data Acquisition System Based On Single Chip Design

Laboratory construction and based on the working process of the curriculum development is the higher vocational education, two very important link. The project is to design and produce a laboratory data acquisition system, To achieve the testing laboratory signals collection, conversion, the processing function. These signals include temperature and smoke sensor output signal. This system combines the vocational college a variety of electrical automation technology professional course content. The course includes electrical and electronic technology, electrical measurement technology, sensing detection technology and instruments, microcomputer control technology and interface. The device production is completed, it can complement the school the experimental project and lab equipment. It also can be used as a comprehensive training programs to provide students with more based on process training opportunities.This is used in higher vocational college students the experimental setup. Therefore, laboratory equipment requires a certain security and openness, Be easy to operate, to help students understand and use. Based on the above considerations, system using AT89S51microcontroller, DB18B20digital temperature sensor, MQ-2analog smoke sensors, analog-digital conversion circuitry, keyboard input circuit and the LED display circuit, buzzer alarm circuit modules. About software, each module have flow chart, Using Assembly Language Programming, It can realize to the temperature, smoke detection, display, the alarm limit setting, delay alarm functions. Students can learn analog and digital two different types of sensors. DS18B20is the latest DALLAS semiconductor company an improved intelligent temperature sensor. Its input/output USES digital, through a single bus, realize the bidirectional communication with MCU. But it's program is complicated. For analog smoke sensor, after converting connected with MCU. Analog smoke sensor module can be divided into operational amplifier and A/D conversion circuit.This is a simple structure, stable performance, easy to use, inexpensive, intelligent experimental device. With the market of molding compared to products, not only greatly reduce the economic cost, but also to cultivate the students' practical ability and professional skills.