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Water is one of the valuable natural resources of the earth. With the rapid economic development, the increasing demand for water, growing water scarcity. Groundwater as a human can use one of the fresh water resources, its reasonable protection and development in order to achieve sustainable development of water resources. Paper groundwater level data acquisition system analysis and design, has important practical significance. Designed according to the characteristics and needs of the groundwater level data acquisition system, based on the AVR microcontroller groundwater level data acquisition system, the detailed design of the hardware and software of the system. The system can real-time acquisition groundwater level to the U disk or SD card via a single-chip processing storage, and through PC software waveform display. The paper analyzes the characteristics and needs of the groundwater level acquisition system, the groundwater level data needs to be collected for a long time, and the need to work long hours in the field, which requires reliable data storage and large data storage capacity. Therefore, the system selects powerful ATmega128 microprocessor, 16-bit low-cost, high-resolution AD7705 as A / D converter, as well as U disk or SD card as a data storage tool. Based on the needs analysis, the overall design of the groundwater level data acquisition system. The design of the sensor circuit, the amplifying and filtering circuits, A / D conversion circuit, keyboard operation circuit, the real-time clock chip interface circuit, USB interface, SD card interface and the interface circuit. Multisim software for data acquisition part of the circuit simulation testing, analysis and simulation results. Using Altium Designer software for circuit schematic drawing and PCB board production. Part of the development and design of the system software the the completed system hardware circuit based on the high-level language C language. Designed data acquisition, data storage, keys, temperature processing, and I2C procedures. In order to facilitate the observation and testing, development of LabVIEW graphical programming language-based PC software, the design of the serial port initialization, data acquisition, data display and save the data of four modules. Modular debugging, and LabVIEW software serial debugging software on the system overall test results show that the system to complete the data acquisition, processing, display and storage, with small size, low power consumption, low cost, reliable and other advantages.
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