PCD3312及其IIC总线接口的驱动

文章介绍了带有IIC总线接口的DTMF编码芯片PCD331 2。通过设计虚拟IIC总线 ,实现了PCD331 2在不具备IIC总线接口功能的MCU控制下 ,产生DTMF信号的方法。     

基于软件模拟的51单片机IIC总线的实现

文章在简述IIC总线的基础上,介绍了通过软件模拟来实现IIC总线在MCS51系列单片机中的应用,从而使不带IIC总线接口的51单片机,也能扩展IIC总线接口器件。同时,以访问IIC总线接口芯片EEPROMAT24C02为例,并且给出具体程序来说明软件模拟的实现过程。     

基于ARM-Linux的IIC串行通信

随着计算机技术的不断发展,以ARM芯片为处理器的产品越来越多。外围芯片与ARM通信方式也多种多样,飞利浦公司推出IIC总线就是其中的一种。本文以AT24C02为例纤细介绍了IIC总线的通信方式,并着重介绍了基于ARM-Linux的IIC总线设备的驱动编写。     

基于IIC总线技术的视频信息采集系统

使用IIC总线技术实现视频信息的采集,系统的开发采用了CMOS图像传感芯片OV7620和可编程逻辑阵列器件。OV7620的内部寄存器是通过IIC接口访问的。两根IIC总线分别是串行时钟线和串行数据线。FPGA产生IIC总线时序、对OV7620系统上电初始化和同步输入,使OV7620输出的采集信号达到图像压缩的要求。     

基于IIC协议的计算机对芯片的控制

IIC协议广泛应用于计算机与芯片、芯片与芯片的通信中,通过芯片的IIC接口,计算机可以监测、控制芯片工作状况,本文分析了IIC总线及其协议规范,并设计了计算机与芯片IIC通信的接口电路,对实现计算机与芯片通信很有意义。     

IIC总线IP核的改进研究

针对IIC总线IP核的可复用性、鲁棒性要求,通过改进IIC总线控制器的组成模块与端口,设计用于SOPC的IIC总线IP核改进过程中,针对传统IIC总线页写操作存在的数据溢出隐患的问题,对读写模式进行了优化控制,并在保证IIC端口功能完整的前提下提高了端口配置性,改进的IP核进行了软件仿真验证和硬件验证,结果符合预期,研究过程与结果,为提高SOPC设计效率、增加数据传输的鲁棒性提供有益参考。     

基于FPGA的可配置IIC总线接口设计

针对传统IIC总线接口的FPGA设计可重用性不高的问题,提出了一种基于FPGA的可配置IIC总线接口设计方案。该方案采用同步有限状态机设计方法和硬件描述语言Verilog HDL, 对IIC总线的数据传输时序进行模块化设计,采用Signal Tap II对设计模块进行仿真验证。实验结果表明,该设计接口作为一种主控制器接口,可实现与具有IIC总线接口的从机器件100kb/s和400kb/s的可靠数据传输。该方案具有可重用度高、可配置性强、控制灵活等优点,并已成功运用于工程实践中。     

提供容性缓冲的双通道和四通道IIC多路复用器

凌特公司推出两线总线多路复用器LTC4305和LTC4306,这两款器件在上行IIC总线连接到所需的下行总线组合时提供了容性隔离。软件控制的LTC4305多路复用两个通道,而LTC4306将IIC总线分裂成四个子分支。IIC多路复用容许多个系统管理总线和多个IIC器件可靠切换。多路复用还允许地址扩展以及对多个相同器件之一寻址,因此解决了地址冲突问题。这些器件可应用在各种计算机中,包括工作站、服务器和台式PC。LTC4305和LTC4306不受电源限制,不论该集成电路的电源电压是多少,每个通道都可以拉高到2.2～5.5V的电源电压。这种电平转换无需第…     

基于Verilog HDL的IIC总线IP核设计

设计片上系统时往往需要各种数据接口,为了解决片上系统间的数据传输的实际需求,设计了一种更为简捷的IIC总线接口,并利用Verilog HDL 语言进行了IIC总线IP核的设计,使得所设计的IIC总线接口具有良好的移植性,实现了不同速率模式下的数据传输,可以方便地应用到片上系统、各类集成电路数据接口等设计中。     

基于LA76818A的彩电故障演示系统的设计

本文介绍的是采用单片集成电路 LA76818A 研制数码 IIC 总线遥控彩电原理及故障演示装置,在实践教学过程中,学员既可以直观地看到电视机内部电路,又可以设置各种故障现象。设计中引用了智能控制、IIC总线技术、遥控技术、图像加强等新技术,解决了电路原理和印刷电路在实际应用过程申经放大出现的干扰问题。     

基于单片机通用IO口的SPI接口模拟

IIC接口是一种同步串行通讯接口。为了扩展系统接口,有时必须要模拟出IIC串口。提出了基于TI的MSP430系列单片机利用通用I/O口软件模拟出了IIC串口的方法,提高了IIC的接口效率,简化了其使用方法,并且给出连接IIC接口的24C01型EEPROM的实例。     

新型多弧离子镀膜机自动控制系统

利用工控机(IIC)和PLC研制成了新型多弧离子镀膜机自动控制系统,该控制系统可以实现镀膜工艺过程的自动控制.工控机设定技术参数后进入监控状态,实时监测控制PLC的工作状态;PLC控制现场设备的运行,并将现场各泵阀等设备的工作状态传给工控机.系统可靠性高,人机交互好,实现了多弧离子镀膜的自动控制.     

数字温度传感器DS1621在Linux下的IIC接口驱动设计

针对目前IIC总线以及具有IIC接口的芯片在嵌入式系统中的广泛应用,设计了一种基于ARM9平台S3C2440的,Linux操作系统下的IIC接口设备驱动程序。通过IIC总线协议,驱动程序实现了在内核状态下对数字温度传感器DS1621的配置和获取其温度信息,并将其传回用户空间并打印显示。实验结果表明,工作时典型数据更新时间为1 s,精度为小数点后一位。且利用多片DS1621可扩展一个低电压、低功耗的多点数字测温系统,在嵌入式设备的温度监测方面将有着广泛应用。     

IIC总线在移动智能终端领域中的应用

本文介绍了IIC总线的优势,结合智能机设计的发展趋势,重点论述了如何使用IIC总线实现越来越多的传感器等IIC设备之间的正确区分和访问,IC厂商和手机设计者如何使用可配置地址解决设备地址冲突问题,以及在实际应用过程中,如果使用辅助中断来解决IIC总线一主多从模式下从机无法主动上报信息的问题.     

Symbolic large-signal simulation of switched circuits

To improve the simulation efficiency of switched circuits, it is advantageous to model their switching devices as short and open circuits. The disadvantage is that such models may cause inconsistent initial conditions (IIC), and Dirac impulses may appear. Conventional simulators do not handle such situations correctly. This paper introduces a new algorithm for analyzing circuits with IIC by a mixed numerical-symbolic method. The method detects the order of the Dirac impulse and also finds the correct initial conditions after switching. It is applicable to nonlinear circuits.     

Modeling of the hot electron subpopulation and its application toimpact ionization in submicron silicon devices-Part I: transportequations

Impact ionization (II) in three different n⁺-n^- -n⁺ device structures is investigated using self-consistent Monte Carlo simulations. A subset of electrons participating in II-referred to as the hot electron subpopulation (HES)-is identified. The data obtained from the Monte Carlo (MC) simulations indicate that the average energy of the HES (ω˜) is an appropriate variable for the macroscopic quantification of II in all the devices under consideration. In order to calculate ω˜, a set of macroscopic transport equations for the HES is derived from the Boltzmann transport equation and calibrated using data from the MC simulations. Numerical solutions to the proposed II model applied to the three devices considered here will be presented in Part II. Therein, values of the II coefficient (IIC) predicted by our model will be compared to those obtained from our MC simulations and also to IIC values predicted by models proposed earlier by other authors     

Development of an intravascular impedance catheter for detection offatty lesions in arteries

Recent studies show that the presence of fatty lesions in the atherosclerotic vessel wall is a risk factor for acute occlusion of blood vessels. Although fat has a high electrical resistivity, existing impedance catheter systems cannot be used for detection of these lesions because artifacts owing to impedance variations in the extravascular surroundings have a major and irretraceable effect on the measurement. Standard algorithms used in attempt to compensate for these artifacts suffer from severe instability problems. The authors defined design guidelines to be met by a new impedance catheter system in order to make a robust reconstruction algorithm possible and have built an experimental in travascular impedance catheter (IIC) system according to these guidelines, using a normalized differential measurement procedure. With this IIC, the authors performed experiments on human iliac arteries from the section ward (fixed specimens), showing that plastic models of arterial fatty lesions (8 mm³) can be detected reliably     

Successive interference cancellation algorithms for downlink W-CDMAcommunications

In this paper, successive intracell interference cancellation (IIC) of the wideband-code division multiple access (W-CDMA) signal at the mobile unit is considered. Three new interference cancellation techniques suitable for the downlink of any CDMA system with orthogonal spreading are proposed. No prior knowledge of users' spreading codes or even their spreading factors are required for interference cancellation. A new term, effective spreading code, has been introduced, which is defined as the interfering user physical code as seen by the desired user within the desired user symbol duration. The mobile receiver estimates the effective spreading codes of the interfering users regardless of their spreading factors using fast Walsh transform (FWT) correlators (instead of the regular correlators) and uses this information to suppress the intracell multiuser interference. Three different interference-suppressing techniques are studied: subtraction; combined interfering signal projection; and separate interfering signal subspace projection. The complexity of the proposed techniques is low compared to conventional interference cancellation techniques. For a W-CDMA system and the IMT-2000 vehicular channel model, a capacity increase of up to 150% of the original (without IIC) system capacity is shown