基于Keil时序逻辑和Proteus的电路仿真

针对Proteus仿真液晶LCD1602出现的问题,对LCD1602技术手册中的读写操作时序图进行LCD1602相关引脚时序逻辑电平分析,通过Keil4的逻辑分析仪对程序中LCD1602的读写时序进行查看,根据逻辑分析仪的时序波型对液晶显示程序代码进行修改使程序符合LCD1602的读写时序要求,并使用Proteus的图表分析对电路程序代码执行时的电平进行查看,直观显示了程序在电路执行的过程。在嵌入式系统开发中使用Keil4时序逻辑及Proteus图表仿真,可以对软件及电路中出现的问题有针对性的分析,探索了使用Keil4的逻辑分析仪和Proteus的图表分析对程序执行时序进行分析的新方法。     

单片机扩展8255控制LED数码管动态显示仿真教学

高校机电一体化专业单片机教学过程中,扩展8255和LED数码管动态显示两部分内容学生普遍反映难以掌握.对此给出单片机扩展8255控制LED数码管动态显示仿真教学案例,通过程序单步调试和时序图分析,把难点形象直观地展现在学生面前,利于学生掌握8255和LED数码管的使用.     

PLC程序的时序分析编程法

介绍了时序分析法的基本原理及注意事项,编程步骤为前期处理、分析问题、绘制时序图、资源分配、程序编制和调试优化.举例说明了此方法的具体应用过程.     

基于Proteus的单片机模数转换电路的设计与仿真

以单片机控制A/D转换器TLC549为例,对A/D转换器的主要技术指标进行了分析研究,在Proteus平台下,完成了A/D转换电路的构建,采用器件工作时序方式进行程序编写,借助仿真图表、虚拟仪器等工具对A/D转换的数据进行测量并对失调误差、增益误差、微分非线性、积分非线性和转换时间等重要参数进行了详细分析。结果表明:使用Proteus软件可对A/D转换过程进行定性分析,将抽象的A/D转换器技术指标直观化、形象化展现出来,有助于学生更好地理解A/D转换过程。     

次态卡诺图在时序逻辑电路分析和设计中的运用

通过实际例子 ,阐述了次态卡诺图在分析和设计时序逻辑电路中的使用方法。该方法的使用可以使时序逻辑电路的分析和设计得到一定的简化 ,过程中思路清晰 ,状态转换直观。     

次态卡诺图在时序逻辑电路分析和设计中的运用

通过实际例子,阐述了次态卡诺图在分析和设计时序逻辑电路中的使用方法。该方法的使用可以使时序逻辑电路的分析和设计得到一定的简化,过程中思路清晰,状态转换直观。     

基于USB2.0和FPGA的高速数据采集卡

介绍一种采用USB2.0接口与PC机进行数据传输的高速数据采集卡的设计。采集卡由可变增益放大器对采样信号进行预处理,使用异步并行的A/D转换技术实现40 Msps的数据采集,由FPGA实现时序控制和数据高速FIFO,由内嵌MCU的USB控制器实现USB2.0接口功能。文章给出了硬件的基本结构和软件固件设计的基本方法,并对用FPGA设计FIFO作了重点阐述,同时对使用异步并行A/D转换与使用采样率为40 Msps的ADC器件的采样数据在FIFO内的数据传输进行了时序仿真,分析了仿真结果。     

Siemens 200仿真软件在PLC控制系统设计中的应用

介绍了Siemens仿真软件对Siemens200系列可编程控制器的常用编程方法、继电器电路设计梯形图的经验设计法和顺序功能图设计法所设计出的程序进行了仿真验证,并对相应时序变量实时监测。结果表明,该方法效果完全与硬件调试一致,为教学和工程实际实践提供了一种非常有用的方法。     

LSI功能测试与仿真模型的研究

在实际实验教学过程中,提出了一种基于指令与时序级的LSI功能测试与仿真模型的原理,根据仿真库模型实现对LSI的功能测试。主要包括外部模型、内部驱动模型、时序模型、功能模型等测试模型,测试结果通过静态功能、时序、波形等方法进行逻辑综合。系统可以实现电平测试、时序测试、指令测试等测试方法,达到对不同芯片的功能测试要求。     

基于Proteus的单片机中断电路的设计与仿真

针对单片机中断程序执行中异常状态多、偶发性和隐蔽性比较突出等问题,设计了由AT89C51单片机、外部中断电路、串行口中断电路和中断指示电路组成的基于Proteus的单片机中断电路。在Proteus仿真平台下完成硬件电路的搭建,对Keil C与Proteus软件进行联合调试,借助Proteus提供的虚拟仪器、激励源和仿真图表等仿真工具对电路运行情况进行实时观测和精确分析。该单片机中断电路可分析多中断源共同作用下的动态执行过程,可将抽象的中断过程直观化,有助于分析调试过程中存在的问题。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.