【作者】 包秀荣；

【导师】 白凤山；

【作者基本信息】 内蒙古大学 ， 信号与信息处理， 2005， 硕士

【摘要】 随着信息化及网络化的发展,越来越多的工业现场过程参数的传输控制采用现场总线技术,其中CAN总线由于其优越的性能已被广泛地采用。 本文根据泵站水池液位连锁问题,提出并设计了一种采用CAN协议总线作为数据传输手段,对泵站水池液位进行实时采样和显示,超出水位上下限时发出报警信号,从而达到对水泵电机进行控制目的。本设计为一个分布式CAN网络中现场数据采集、监控节点,利用CAN可以很容易扩充以实现分布式数据采集传输系统,为企业进一步实现网络化管理奠定了基础。 该系统在结构上主要包括现场液位数据采集、单片机、数据显示及报警、CAN总线协议转换等单元。液位数据经A/D转换送单片机处理,并实时显示。若超出设定的液位安全限,则产生报警信号,同时对采集数据进行CAN协议格式转换,经CAN驱动送到CAN总线上传输。CAN网络上其它节点可以接收本节点发出的数据,同时本节点也可以接收其它节点送来的数据,即在CAN网络上实现多主传送方式。 为了减小体积,提高运行的稳定性和可靠性,本系统在电路设计、器件类型、制版方面都做了精心的考虑,如采用“看门狗”对系统运行监控,软件上采用了数字滤波等方法。系统软件用C编写,采用模块化结构,在减小软件体更多还原

【Abstract】 With the development of information and network, the more and more parameters of process control in industry use the Field Bus technique, one of that, CAN-bus has come into wide use because of its superiority properties.According to an actual problem of monitoring water level at a pump station, this thesis proposes and designs a system used the CAN-bus as the mean of data transmission. The system can do real-time collect and display water level of a pool in pump station and also give an alarm signal if the water level exceeds the upper or lower safety limit of water level, so that electric pump at pump station can be controlled on or off. This system is used as a node of local data acquisition and monitoring in a distributed CAN network, and it is easy to be expanded by using CAN-bus for composing distributed data acquisition, transmission system. This builds the basis of realizing further networking management for enterprises.This system consists mainly of local water level data acquisition, single chip computer, data display, alarm, CAN-bus protocol node unit, etc. The water level data is processed in microcontroller AT89C52 through 12 bits serial A/D conversion anddisplayed in real-time by LED. If water level exceeds the safety limit of water level, the system gives an alarm signal and then sampled data will be transmitted on CAN-bus when converted in format using CAN protocol conversion chip SJAlOOO.In CAN network other nodes can receive data sent from this node and this node can receive data from other nodes also. So multi-host transmit mode is realized in CAN network.In order to decrease volume of system hardware and improve stability and reliability of system operation, the circuit structure, devices and PCB design used in this system are considered carefully, such as "watchdog" monitoring and digital filter in software. The software programmed by C language adopts a modular structure for decreasing volume of software, improving code efficiency and reliability of operation.更多还原