双步进电动机等幅摆动单片机控制

在光纤编码成像系统中，为了实现图像编码和解码，需要两套能精确同步摆动的机构。在本文中，我们选择了单片机控制的双步进电动机驱动方案，并论述了这一方案系统的组成、各部分电路和连接线路。     

Field-Oriented Control of a Standard AC Motor Using Microprocessors

Field orientation has emerged as a powerful tool for controlling ac machines such as inverter-supplied induction motors. The dynamic performance of such a drive is comparable to that of a converterfed four quadrant dc drive. The complex functions required by filed-oriented control may be executed by microprocessors on line, thus greatly reducing the necessary control hardware. It is shown that the flux signals may be derived from sensing coils or, with some compromise in performance, from the stator voltages and currents. The speed signal is obtained from a digital tachometer. Results from a 2-kW experimental drive are given.     

Microprocessors in Preengineering

The use of microcomputer systems for an elective sequence in our preengineering program at a liberal arts college was motivated by student requests for assembly language programming and for computer courses oriented more toward the sciences. We describe a very modestly priced system and two courses which are based on the Intel 8080A.     

A Digital Control Laboratory

A laboratory facility is described that provides for the experimental study of digital control systems. The activities of the laboratory are designed to permit experiments in data conversion, data acquisition, hybrid system simulation, computer control of typical physical processes, and binary and decimal data transfer between a digital computer and peripheral equipment. The main facility of the laboratory is a PDP-8 computer, a small general-purpose computer. The laboratory program is part of an educational program in the study of discrete systems and computer control system. This program is also briefly described.     

Microprocessors in electric power systems

The present status of microprocessor applications in various fields of electric power systems is summarized. Special attention is directed towards development trends in the protection field where microprocessor applications are expected to cope with the increasingly stringent requirements for electric power supply reliability. Also discussed are the history, roles, design philosophy and basic schemes of microprocessor-based protective relaying systems. Only recently has their application reached a practical stage after long-term study and repeated field tests.     

Teaching Microprocessors to Exceptional Students

Recognizing the industry demand for students who are knowledgeable about microprocessors on the one hand and student curiosity about the topic on the other, the author was caught between a saturated curriculum and a total lack of financial support. With a number of enthusiastic students and some privately owned equipment, a club was started to give students an opportunity to work with the available hardware and software. As the club solidified, a low key teaching/learning style developed which produced a highly knowledgeable student in computer hardware and programming languages with surprising programming skill. The club is an important part of the Department of Electrical Engineering now, where microcomputer-related topics are taught effortlessly to interested and motivated students without the performance/time pressure of the classroom.     

Microprocessors: Problems of Getting Started

Microprocessors, being new, require courage and determination to investigate. A methodical approach to the study of microprocessors is essential. To understand microprocessors it is necessary to familiarize oneself with digital techniques. Then one can start to read some simple literature on microprocessors. Magazines should also be consulted; and to crown one's effort, one needs a microprocessor development kit. Jumping straight to manufacturers' manuals may be discouraging to a beginner because of their highly technical nature. After acquiring some confidence with the kit, one can choose a particular microprocessor and attempt a simple design. Some microprocessors are more complex than others, so starting with a simple one like the M6800 or the Intel 8080 is advised. Effort should continue in this manner.     

A Design Oriented Feedback Control Laboratory

A set of six laboratory experiments has been developed and successfully used in a senior level feedback control course. In addition to reinforcing the lecture material, the experiments are used to expose the students to a variety of physical systems so they can better appreciate the applications of control theory. The major laboratories are run as design projects in which the students are given a system to be controlled and a set of desired performance specifications, and are asked to design a controller to meet those requirements.     

When Should We Teach Microprocessors?

We all agree that tomorrow's engineer must have a working knowledge of microprocessors/microcomputers, especially as related to a myriad of applications. But there appear to be two schools of thought on how this should be done. Spokesmen for these schools might state their positions as follows: (A) We have a real opportunity to teach the subject to freshmen, making use of it to motivate students and give them engineering early. Such working knowledge will make it easier to understand later courses in operating systems, computer architecture, computer languages. (B) Sure, housewives and grade school kids can understand microprocessors, but our engineers deserve better. Give the EE's a strong background in computer fundamentals, and then show them the beauty and simplicity of the microprocessor when they can really understand it. Besides, the make-shift and sloppy ideas and techniques introduced in a "baby " source will surely inhibit a strong educational program which is to come later. What do you recommend?     

Microprocessors: The Key to Cost-Effective Instrumentation

Recent instrumentation developments, paralleling the advances of the microelectronics revolution, have changed the basic character of instruments. Most significant has been the substitution of microprocessors and software for hardware to produce virtual instrumentation. An experimenter using virtual instrumentation communicates with a microcomputer and software via a keyboard to electronically configure the system hardware to meet his measurement needs. Versatile, cost-effective prototype systems have been developed for undergraduate laboratories. The encouraging results of these prototypes and further technological advances suggest a bright future for virtual instrumentation.     

An Introductory Course in Microprocessors for Freshmen

Suggestions for faculty who wish to "retrain" and develop their own course in microprocessors are presented along with the author's ideas about selecting a particular microcomputer system for such a course. (The AIM-65 in this case.) Class format and the number of students/unit are also discussed. Course structure and content are described in detail. A week-by-week breakdown of the course topics, in class exercises, and home assignments is given. The overal philosophy underlying the course is that to keep the interest of freshmen, it is necessary to have a "hands-on" approach. This has proven to be correct.     

基于ARM微处理器的嵌入式以太网接口

在电子设备日趋网络化的背景下,作为目前广泛使用的以太网以及TCP/IP协议已经成为事实上最常用的网络标准之一,它以高速、可靠、分层以及可扩充性使得它在各个领域的应用越来越灵活,很多情况下运用以太网和TCP/IP,能够简化结构和降低成本。但是,目前关于嵌入式以太网的设计方案不是很多,在这不多的方案中,大多是基于单片机或DSP的。两者都存在要外扩很多外设的问题,并且前者速度太慢,后者成本又太高,这在一些对设备尺寸要求很小的场合是不行的。本设计中,采用了基于ARM内核的微处理器S3C44BOX为基础的嵌入式系统与10　MB以太网控…     

New Experiments for a Control System Laboratory

Traditionally automatic control laboratories are mainly devoted to study of the classical servoposition control system and rely heavily on electromechanical components. The purpose of this paper is to present two unusual experiments (a light control system and a temperature control system) which have been designed to illustrate the application of control theory to a wider class of problems.     

Virtual Laboratory for Creative Control Design Experiments

This paper proposes a two-step strategy for the computer-aided learning of control. A virtual Web-based laboratory for control design experiments (http://www.hl1.uni-mb.si), which supports a two-step strategy, is based on the MATLAB Web server (MWS) and consists of two virtual laboratories. The first virtual laboratory, called ldquoWeb sisotool,rdquo supports computer-aided control design and structured hands-on experiments. Computer-aided control design is welcome as a design tool while structured hands-on experiments are welcome for the visualization of hard-to-grasp concepts. The second virtual laboratory offers students an unstructured MATLAB-like environment, called ldquoM-file application,rdquo that allows students to create and design control design experiments by writing MATLAB M-files of their own and executing them on MWS. The presented virtual laboratory for control design experiments is cost effective and has already been successfully used for the learning of control. Student feedback is also presented.     

校准实验室内部质量控制的实施

文章对实验室内部质量控制方法及实施进行了探讨,通过具体实例说明内部质量控制方法的选择使用.     

用VB实现PC机与MCS-51单片机的主从式通信

主要针对多台ＬＥＤ 显示屏系统数据传送问题, 提出一种用Ｖｉｓｕａｌ Ｂａｓｉｃ 语言实现的ＰＣ机与多台ＭＣＳ—５１ 单片机主从式通信方法, 给出硬件电路图、通信协议及软件流程图