基于PIC单片机的永磁无刷直流电机控制系统

本文简要介绍了PIC16F877A单片机的基本性能,又以永磁无刷直流电机为控制的对象.分析了PIC16F877A单片机在电机控制中的应用,并给出了硬件设计方案、软件策略及最后结论.     

PIC单片机控制Modem的串行通信设计

本文简要介绍了PIC16F877A单片机的同步/异步串行接口USART模块基本性能,又以Modem为控制的对象,分析了PIC16F877A单片机在异步和同步串行通信的应用,并给出了硬件设计方案、软件策略及最后结论。     

基于PIC16F877的USB接口设计

本文首先介绍了Microchip公司的PIC16F877单片机和Philips公司的PDIUSBD12USB接口控制芯片,然后以PIC16F877单片机和PDIUSBD12接口控制芯片为例,介绍了USB接口的硬件设计和软件设计实现。     

JHD161A LCD显示器与PIC 16F877单片机的连接

较详细地介绍了JHD161A LCD显示器的功能结构及其应用过程中的注意事项，并给出了与单片机PIC16F877的连接方式。     

一款高性价比的PIC单片机学习开发器材

由于PIC功耗小,抗干扰性强,因此PIC的产品多用于一些环境恶劣、干扰复杂的应用领域。下面,我们来看一下学习PIC单片机需要准备哪些软硬件环境以及PIC单片机学习、开发的大致流程。我们需要准备的硬件设备有:计算机一台,PIC仿真烧写器一台,单片机芯片一片,如PIC16F877A芯片(它是PIC单片机家族中非常经典     

基子PIC16F877的汽车用车速表和里程表的设计

汽车的车速表和里程表用于指示汽车的行驶速度和行驶的里程数.目前的汽车仪表主要有以下几种形式:a:机械式(用软轴)b:动圈式(用动圈机芯)c:十字机芯(用8190、8191系列芯片).随着汽车技术和单片机技术的发展,越来越多的汽车仪表开始使用单片机来控制.本文介绍的是用PIC16F877单片机来控制步进马达指示行驶速度,控制步进马达驱动机械计数器显示行驶的里程数,同时还用PIC16F877单片机中的EEPROM保存行驶的里程数.     

基于PIC16F877A单片机的隔爆软起动器控制器

阐述了以PIC16F877A单片机为核心的软起动控制器的设计,硬件电路介绍了MCU的选型、电路的工作原理,并对单片机的管脚进行了分配.软件方面编写了控制器的程序结构流程图.     

基于PIC16F877和RA8835的液晶显示界面的设计

介绍了PIC16F877单片机和RA8835液晶控制器的主要功能和特点,提出了一种基于单片机和液晶控制架构的液晶显示界面的设计方案,并给出了具体的接口电路以及相关的驱动程序。     

基于PLC接口的智能数码显示表头的设计

本文以用PIC16F877加少量外围电路构成的LED数字显示表头为例,介绍PIC单片机智能表头的硬件电路原理和软件编程方法,并给出了用三菱公司的FX系列PLC编制的单表显示例程和PIC的控制显示流程图.     

电热水器智能化系统设计

本文主要介绍了电热水器的定时保温控制系统的设计.根据系统的特点,设计分为时钟定时部分、温度采集部分和电源控制部分.本设计的时钟设定及显示功能利用PIC16F877A芯片来完成,温度采集部分由温度传感器DS18B20来完成,电源控制部分由继电器来完成,同时利用PIC 16F877A的RB端口来控制电热水器开关及输入调整时间和温度.     

An improved immersed finite element particle-in-cell method for plasma simulation

The particle-in-cell (PIC) method has been widely used for plasma simulation, because of its noise-reduction capability and moderate computational cost. The immersed finite element (IFE) method is efficient for solving interface problems on Cartesian meshes, which is desirable for the PIC method. The combination of these two methods provides an effective tool for plasma simulation with complex interface/boundary. This paper introduces an improved IFE–PIC method that enhances the performance in both IFE and PIC aspects. For the electric field solver, we adopt the newly developed partially penalized IFE method with enhanced accuracy. For PIC implementation, we introduce a new interpolation technique to ensure the conservation of the charge. Numerical examples are provided to demonstrate the features of the improved IFE–PIC method.     

Analysing the convergence behaviour of the PIC detector

This paper analyses the convergence behaviour of the parallel interference cancellation (PIC) detector in code division multiple access (CDMA) systems. The paper introduces a general PIC detector model where it can be used to describe the interference cancellation process of the PIC detector with any type of tentative decision function. With this model, the PIC detector can be viewed as either a feedback system or an iterated-map neural network. Using the known results from previous stability analysis in these areas, the paper derives general conditions from which the sufficient condition for convergence of the PIC detector for a wide range of tentative decision functions can be calculated. As examples, the paper derives the sufficient condition for convergence of the PIC detector with linear decision, clip decision and hyperbolic tangent decision functions.     

Parallel particle simulation in high voltage diodes (Algorithms and concepts for implementation on SUPRENUM)

A two-dimensional Particle-In-Cell (PIC) code has been developed in order to support the experimental investigation of pulsed power ion diodes by numerical simulation. The PIC code serves to simulate the orbits of electrically charged particles in electro-magnetic fields. Most modules of the PIC code have been vectorized; for parallelization the logical structure of the code is being considered. In this paper we introduce the idea of a PIC code, outline the single modules, and present concepts for implementation on SUPRENUM.     

PIC16C74单片机应用与编程探讨

PIC系列单片机以其高性价比获得了日益广泛的应用,本文以PIC16C74为对象,对它的实际应用与编程中的一些具体问题做一探讨。     

基于Pcomm的PC机与单片机串行通信的实现

讨论了用Pcomm软件包实现PC机与PIC系列单片机串行通信的方法，从硬件设计，PIC单片机通信程序设计，C＋＋环境下使用PcommLibrary软件包的有关函数编制PC机的通信程序等方面进行论述，并简单介绍了PIC单片机串行通信的基本原理，给出了具体的通信程序。     

Estimating percent impervious cover from Landsat-based land cover with a simple and transferable regression model

Percent impervious cover (PIC) is a widely used metric in ecological and hydrological analyses because it is highly correlated with pollutant and storm water run-off. The moderate-resolution satellite data (e.g. Landsat), that are typically used to calculate PIC, tend to overestimate PIC for all but very rural and very urban landscapes. Existing models for calibrating PIC estimates (e.g. ISAT, ETIS) are limited in that they are applicable only for specific land cover datasets and may also require population data; furthermore, these models have not been tested for performance outside of the geographic locations in which they were developed. The goal of this study was to explore simple but widely applicable regression models as tools for calibrating PIC estimates based on moderate resolution satellite data. The regression models used impervious land cover, from Landsat-based datasets, as the sole predictor of actual PIC. PIC was calculated for analysis units, ranging in size from 2.25 ha to ≥100 ha, for locations in Connecticut, Massachusetts, and Ohio in the United States. Regression models were fit for each size class of analysis unit at each study location; generalized versions of the models were created by fitting a regression to all size classes of analysis units at a given study location. Calibrated PIC estimates had root mean square error (RMSE) values that ranged from 1.5–10.7%; these values were considerably better than RMSE values for uncalibrated PIC estimates which ranged from 10.1–23.3%. For both calibrated and uncalibrated PIC, the accuracy of the estimates improved with the increasing size of the analysis units. Model regression coefficients were similar regardless of the analysis unit size, geographic location, or land cover dataset; model performance declined only slightly when applied outside the area in which it was developed. The simple regression models developed in this study had similar performance to previous calibration models (i.e. ISAT, ETIS) but are easier to apply and more widely applicable.     

用VIS验证微处理器PIC

近年来,二叉判定图ＢＤＤ和符号模型检验在形式验证数字电路设计中取得了突破性进展,文中介绍了符号模型检验的基本原理和方法,重点介绍了如何用ＶＩＳ系统验证微处理器ＰＩＣ设计的正确性。利用ＶＩＳ证明了ＰＩＣ设计部分电路的等价性。发现了一个设计错误并证明了ＰＩＣ中一些重要模块的特性。     

An information age opportunity — Providing information for customers

Evolutionary growth of the use of information technology in business operations now provides a new information-age opportunity for managers, that of providing information for customers (PIC). In the PIC applications, information is a product not a resource and the product is information, not data. Pertinent examples of firms using PIC and steps to be taken by any firm that desires to implement this concept are explained in some detail. This application of computer technology usually can be implemented at minimal costs. PIC provide competitive advantages to the firm by tangibilizing various information services for customers.     

并行干扰抵消检测对数字窄带干扰的抑制

并行干扰抵消检测被认为是一种很有前途的多用户检测器。该文将其应用于直接序列扩频系统中的数字窄带干扰抑制问题。分析了这种并行干扰抵消检测器在抑制数字窄带干扰时的性能,并将其与部分并行干扰抵消检测的性能相比较。理论分析和仿真结果证明,将接收信号经过一次并行干扰抵消后的输出信号直接应用于数据判决,会得到较好的干扰抑制效果,其误码性能可以达到解相关检测的水平。同时。并行干扰抵消检测还具有抗远近效应的能力,其性能与干扰的能量无关。     

On parallel PIC versatility and the structure of parallel PIC approaches

We discuss insights gained from an effort to develop a versatile parallel PIC code (PICARD – PIC with arbitrary rebalancing and decompositions). Because of the highly dynamic nature of PIC, it is sometimes necessary to tailor decomposition strategies on a problem-by-problem basis instead of solely on the basis of the algorithm. The dynamics of a problem may dictate the particular strategy to be used. Thus, finding a general operational method for parallel PIC applications is important. We find approaches to partitioning the mesh and particle domains which provide some trade-off opportunities, but the relationship enforced between the partition layouts in addition to the way one chooses to manage the problem's dynamics defines categories of strategies which are independent of the partitioning technique used. The overall strategy enforced is as important as the individual techniques applied to partition the domains. Three strategy groups arise from the analysis and form the basis of widely disparate parallel PIC operational methods. These distinct solutions are obtained from rather simple parametric choices. We introduce the concept of rubber boundaries as a means to bring a compromise between what are commonly referred to as Lagrangian and Eulerian particle mappings. We show several parallel PIC strategies that are as yet unexplored. © 1997 John Wiley & Sons, Ltd.