The Development Of Foods Pesticide Residues Detection Control System Based On ARM

This project is a part of "detecting methods and instrument development of pesticide residues in foods", and the aim is to make a set of instrument with reliability, low cost and small volume to work for the pre-processing of pesticide residues analyse, use it to separate and purify food samples, and provide high purificatory samples for chromatogram quantitative mensuration.The paper starts with the character of detecting and analysing pesticide residues in foods, introducing the separation principle of GPC, basic structure and craft flow of pesticide residues chromatogram detecting system. On the basis of craft character and control request, it makes a selection of scheme to the whole control system.Finally a scheme is chosen and described as follows: S3C44BOX is used as the control kernel, and LCD as the display module, the ARM control center communicate with AD sampling board and multiplex I/O control board through Master-Slave structure based on RS485 bus. The control system deals with the signal sampling and control of motors, pump, valve switch, probe, molecule concentration electric signal. Analog signals sample and each output I/O are illuminated, including the flow chart of the software and hardware, and some important circuit diagram of the AD/DA sampling board and multiplex I/O control board.The communication principle and realization in multiprocessor through RS485 bus is disscussed emphatically, and also, the flow chart of the Master based on ARM7 CPU and Slave on 8051 CPU are given. What's more, the transplantation uC/GUI onto S3C44BOX, the realized methods of LCD user interface based on uC/GUI, and the introduction of each practical interface on LCD are given.There is no instrument of detecting pesticide residues in foods in local, if the instrument can be successfully made, it will fully change the state of importing expensive instrument from abroad, and it will provide scientific proof to supervise and test the quantity of pesticide residues in foods, and to improve international fair trade of our national food, which have great significance for our food safety insurance and the pepole's healthy diet.