Abstract
The hardware layout and software development for single chip microprocessor intelligent micro-irrigation system and system programming are presented in detail in this paper. Based on the AT89S51 single chip microcomputer, the micro-irrigation system consists of humidity moisture sensors, signal gathering circuit, keyboard and monitor display circuit, out port control circuit, serial communication circuit,E2PROM reading-writing circuit and irrigating equipments and so on. The system is able to automatically detect the humidity of environment and control the irrigating equipment. Thus, the setting humidity can be modified. The humidity modified will be saved to prevent from that the data is lost when the power is cut off .Then, the gathering humidity of environment and setting humidity will be sent serially to the computer . On the other hand, the computer can modify the setting humidity of the micro-irrigation system by the serial communication. So we can use the computer to manage the micro-irrigation system.
As far as the design of the hardware is concerned, here chose the S302H5V5 capacitive humidity sensor as the humidity sensor, ADC0809 as the A/D conversion, the touching style key as the keyboard, LCD as the monitor display. The out port circuit is consists of triode, NOR gate, relay, light-emitting diode and so on. The development of software adopts the popular modularized structure and the modularized debug facilities. The design of software adopts assembly language entirely. The primary program is composed of main program, keyboard scanning subroutine, A/D sampling subroutine, serial transmit and receive subroutine, displaying subroutine of LCD and so on.
The successive debug experiments prove that the system is characterized by high reliability, capable control function, controlling by automation and simple operations. In addition, there are some suggestions about the further development and improvement of the micro-irrigation system in this paper.
Key words: intelligence, micro-irrigation, single chip microcomputer