植保喷头综合性能测试专用数控系统的设计

为了研究新的施药方法及施药器械，研制了喷头综合性能测试专用数控系统，该系统能够精确采集总流量、压力、分流量与温度等参数。硬件设计中，选用MSP430F149单片机作为系统的CPU；接口电路设计中，选用74LVC4225作为电压转换芯片，用两片Intel 8255A作为接口扩展芯片，选用HCPL0601高速光电耦合器作为通讯接口电路中的隔离和电压转换芯片；温度的测量是用DS18820芯片实现的。软件设计中，键盘操作及通讯功能的实现是在中断子程序中完成的；算术平均值及比较取舍两种数字滤波技术的运用，提高了采集数据的精度。经过长时间的运行试验表明，系统工作稳定可靠，数据采集精度高，重复性好，具有良好的推广应用价值。

Design of Special Numeric Control System for Test Crop- protection Nozzle Integrative Performance

In order to study new pesticide measures and crop--protection mechanism, a special numeric control system for test crop--protection nozzle integrative performance accurately was designed. The microcomputer MSP430F149 was the CPU of the numeric control system for its outstanding performance. In the interface circuit, the chip 74LVC4225 was voltage shifter. Two Intel 8255A chips was the extended chip. High--speed phototube Hcplo0601 was used in the design of the serial communication circuit. Temperature was measured by DS18B20. In the software, the key and communication functions were realized in the interrupt sub--program. The actual result indicates that system has higher stability, higher acquisition data precision and higher repetition precision , the system has higher application values.