基于LabVIEW和单片机的称重信号采集

在称重方案设计中,为了避免单片机和PC机通信时必须采用串口线连接或USB转串口线连接的弊端,并且更好的适应USB接口正逐步成为PC机的标准接口这一大的趋势的要求。同时克服单片机的处理能力有限,难以满足控制的需求的缺点,采用处理能力强及人机交互好的PC机作为上位机,对采集到的数据进行进一步分析和处理,以达到更高的要求。方便采集信号和实时显示信号变化,更好地实现称重信号采集过程中的的人机交互界面的功能,实现仪器智能化。以STC89C52单片机为下位机、PC机为上位机,基于Lab VIEW2014编写上位机软件,通过USB数据线直接连接单片机USB口与PC机USB口,实现单片机与PC机的串行通信过程,使测试方便、简洁、人性化。包括下位机STC89C52单片机的最小系统设计、CH340通信电路设计、下位机单片机通信的软件设计、上位机Lab VIEW2014通信的软件设计。实现称重系统测试信号智能化。

Acquisition of Weighing Signal Based on LabVIEW and Single Chip Microcomputer

In the design of weighing schemes,PCs with strong processing ability and good man-machine interaction are used as upper computer for further analysis and processing of acquired data in confformity with higher requirement,so as to avoid the disadvantage that serial port line connection or USB plus serial port line connection has to be adopted for communication between the single chip computer and PC,to adapt to the general trend of USB interface becoming standard PC interface,and to overcome the shortcoming that limited processing ability of the single chip computer cannot meet control demand.Signal acquisition and real-time display of signal change are made easier,man-machine interaction is improved in the process of weighing signal acquisition,and instrument intellectualization is realized.Upper computer software is compiled by using STC89C52 single chip computer as lower computer,PC as upper computer and LabVIEW2014 as the base.The USB port of the single chip computer and USB port of the PC are connected directly through USB data line to realize serial communication between the single chip computer and PC for simple,easy and humanized testing.Following contents are included:minimum system design for STC89C52 single chip computer as lower computer,design of CH340 communication circuit,software design for communication of lower computer (single chip computer),and software design for the communication of upper computer LabVIEW2014.In this way,testing signals are intellectualized for the weighing system.