为改善营业窗口的服务质量和工作效率，解决枯燥无序的排队问题，采用STC89C52单片机控制语音芯片、打印机、LCD显示屏来模拟人工叫号过程，完成号码的打印、存储、显示及播报工作；采用MAX485扩展RS-485总线接口，实现分布式串行通信。该系统能满足简单的排队需求，具有开发成本低，占用空间小等优点，有较好的市场应用前景。
上传时间： 2013-10-19
上传用户：yinglimeng
中央空调的温湿度检测系统是空调系统的最基本最重要的控制系统，它的发展必将影响到中央空调性能的发展。文中主要分析并设计了温湿度数据采集电路，单总线接口电路以及液晶显示电路，采用MAX232与现场PC机通信。整个系统的控制器选用单片机AT89S52，温度传感器选用DS2438，湿度传感器选用HIH-4000。在软件设计部分，采用C51编写程序来实现系统各个功能模块的设计。整个系统具有实时性，快速性，稳定性、精确性等优点。
上传时间： 2013-11-04
上传用户：gmh1314
第一章 概述 第二章 微型测控系统常用器件 第三章 工业控制计算技术要点 第四章 单片机存储系统扩展 第五章 标准总线和串行通信 第六章微型机应用系统常用可编程接口芯片 ............................
上传时间： 2014-01-09
上传用户：dbs012280
首先研究CAN总线和SAE J1939协议，提出一种基于MC9S12HZ256微控制器的总线式汽车数字仪表解决方案。详细介绍SAE J1939协议的报文帧格式及应用层协议中发动机相关参数的定义，以及步进电机及其驱动和车速信号的处理方法。该数字仪表系统硬件平台由微处理器和信号采集和信息处理及显示等模块组成。软件设计部分编程实现了对CAN总线和各传感器数据的读取、处理。该系统能够实时反映车辆工况。 Abstract: In this paper，CAN bus and SAE J1939protocol are researched，and a vehicle digital instrument solution based on MC9S12HZ256MCU is proposed.The message frame format and some engine-related parameters’definition in SAE J1939application layer protocol are introduced in detail.Stepper motor and its driver，the methods of speed signal process-ing are also introduced.The hardware platform of vehicle digital instrument is composed by MCU，signal acquisition mod-ule，and signal processing and displaying module.Data receiving and processing from CAN bus and sensors are accom-plished by programming，and vehicle condition can be reflected in real-time.
上传时间： 2013-10-20
上传用户：huannan88
介绍一种基于CAN总线的牵引变电站自动化系统通讯规约的设计，CAN通讯规约采用标准帧，报文采用主动发送和发送查询两种处理形式。该设计在城市轻轨与地铁牵引变电站中的应用表明：可实现间隔层和通讯处理层的数据快速、可靠的交换，提高牵引变电站的安全性和稳定性 。 Abstract: This paper firstly presents a kind of design dealing with communicational protocol to the traction substation automation system based on CAN bus,and then comes up with the ideas that all frames of CAN communicational protocol should adopt the standard frame,and that messages be processed by two ways:sending initiatively and sending quiries.Subway and light rail application shows that the use of the CAN bus is possible to exchange data quickly and reliably between the layers of the middle and the communicational processing,hence to improve the safety and stability of traction substations.
上传时间： 2013-11-07
上传用户：bs2005
介绍基于ISA总线与KH-9300的数据采集板卡的设置，详细说明8254定时计数器及8259中断控制器的结构特点、工作方式、控制字等，探讨中断类型、中断处理程序、中断矢量表及其填写。重点讲述使用TorboC编写中断服务程序的方法，应注意的主要问题及程序测试的结果。 Abstract: The settings of KH-9300 data acquisition board based on the ISA bus is introduced,the structural characteristics,working methods,control characters of the timing counter 8254 and interruptioncontroller 8259 are explained in detail.The interruption type,interrupt handling programs,interruption vector table and its filling also are discussed.Further,great emphasis is put on the method of interrupt service program compiled by Torbo C,the main issues that should be noted,and the results of program testing.
上传时间： 2013-11-14
上传用户：qq527891923
在开放式数控系统结构模型的基础上，研究了基于ISA总线的DSP通信控制原理。采用中断方式完成了PC机和DSP之间的通信。介绍了以DriverWorks为工具开发ISA设备WDM驱动程序的方法，探讨了中断处理、驱动程序与应用程序之间的通信,简要说明了驱动程序的安装与调试。通过调试,系统设计运行稳定。 Abstract: The ISA bus and DSP correspondence control principle is investigated in the basis of the existing open architecture numerical control system.The interrupt method is used to realize the communication between PC and DSP based on the ISA bus.The methods of WDM driver exploitation for ISA device using Driver Works are introduced.The main process of driver program and the keys such as handle interrupt and the communication between the drivers and application are presented.And how to debug and install the drive is explained.
上传时间： 2013-11-04
上传用户：kang1923
对于传统的跑步机无法联机组网，保存历史数据，实时调试等问题，介绍了一个由多台跑步机通过RS-232串行总线与上位机相连组成的跑步机联网系统。系统采用W77E58作为下位机核心控制器件，它具有双串行通讯端口，其中一个串口用于与变频器通讯，另一个串口则与上位机相连，构成跑步机网络。 Abstract: The traditional running machine can not be connected to a network, saving historical data, real time debug etc.In this paper,a new network system which is composed of running machines connected by a RS-232 communication bus is introduced.In the system,W77E58 is used as a core control unit.W77E58 has two serial ports,one is connected to the inverter and the other is connected to the PC. Thus a network appears.
上传时间： 2014-12-27
上传用户：哇哇哇哇哇
针对船舶气象仪保障维修而设计的船舶气象仪测试系统，包括信息处理终端、主仪器检测模块、传感器检测模块，各个模块都采用基于AVR单片机的嵌入式系统，模块之间通过CAN总线进行通信。结果表明，船舶气象仪测试系统能够快速检测船舶气象仪故障，与单纯依靠人工方式排查故障相比，故障检测时间缩短了60%以上。 Abstract: The test system of ship meteorological instrument was developed to satisfy the maintenance of ship meteorological instruments，which composed of information processing terminal， testing module of main instrument and testing module of sensors. Each of these modules included an embedded system based on microcontroller of AVR series and communicated with other module by CAN bus. The results show that the test system can judge the fault of ship meteorological instrument quickly and shorten the fault detection time as much as 60% compared with simple manual troubleshooting.
上传时间： 2013-11-23
上传用户：stvnash
具有PCI总线等接口形式的采集卡虽然传输速率高，但安装麻烦,易受PC机插槽数量、地址、中断资源的限制。为了解决以上问题，设计了基于ISP1581的高速USB接口的多通道数据采集系统，介绍了系统硬件组成以及软件程序的开发过程。经验证，系统最高传输速率可达60 Mb/s。
上传时间： 2013-10-31
上传用户：ANRAN
