Embedded System용 실시간 운영체제 설계 및 구현

柳晳 충남대학교 1999 국내석사

This paper deals with design and implementation of real time operating System for embedded system. Real time system is characterized by the severe consequences that result if logical as well as timing correctness properties of the system are not met real time operating system cover a wide range, but most real time operating are embedded. This means that the computer is built into a system and is not seen by the user as being a computer. On Real-time System, Real time operating system allows real-time applications to be designed and expanded easily; functions can be added without requiring major changes to the software. I design Real time operating system for preemptive kernel. and design kernel component such as Semaphore, Message Mail box, Message Queue, Timer, ISR mechanism has low interrupt latency.

네트웍 시각 동기를 위한 내장형 실시간 운영체제의 시각 관리 방안

전선미 부산대학교 일반대학원 2000 국내석사

The computer clocks have limits in accuracy and precision affected by their inherent instability, the environmental elements, the modification of users, and errors of the system. The purpose of synchronizing clocks in to provide a global time base throughout a distributed system. Two factors must be considered in designing a specific system for time synchronization. One is the clock model and the other is the kernel model. A clock model for time synchronization should keep stable time and provide accurate standard time and precise resolution. A kernel model for time synchronization should be preemptive and support the real-time processing of some important events such as network packet arrival. This paper presents an implementation of a clock management method of embedded real-time OSes for time synchronization and shows a design and an implementation of NTP on the embedded real-time OS such as pSOS. Most of the embedded real-time OSes have a proper kernel feature but the limited time synchronization power because these have the insufficient time management function. The time model should have a reading operation with more 10^(-6) leveled time resolution, a communication interfacing with external clocks. and a clock adjustment policy with monotone clock increasement. First, we design the I/O device drivers for the hardware component of clock model and then implement the time management module. Finally, the embedded time server prototype was tested. The performance evaluation shows the proposed method improves the stability and the precision of time of the target system.

실시간 운영체제 iRTOS 상에서의 TCP/IP 구현

片炫範 충남대학교 2000 국내석사

Embedded systems are facing a new requirement to put Internet connectivity in a wide variety of systems. Connectivity is required either to exchange billing information or business data, or to facilitate remote process and/or machine control. For almost everyone, the TCP/IP protocol suite is the core technology for this connectivity. For many, TCP/IP is now the technology of choice for all data transfers, including both video and voice. This paper deals with the implementation of TCP/IP on the small size real-time operating system, iRTOS(about 21k) on the target system like as a PC or Embedded systems. We implemented modified wattcp(Waterloo TOP/IP), to satisfy characteristics of real-time using both wattcp, it is DOS based free TCP/IP and a DOS packet driver. Also We implemented kernel scheduling data transmission. When a task is ready to transmit data through Networks, it hand the data transmission to kernel and execute next works continuously. Wattcp is developed for single task operation. Because our iRTOS is developed for multitasking, We modified wattcp for additional locking mechanism and priority-order data transmission scheduling.

실시간 운영체제를 위한 가상머신 설계

조희남 忠南大學校 大學院 2004 국내석사

This paper deals with the design of a virtual machine for real-time operating systems. A virtual machine is an abstact definition of a computing architecture that is independent of any particular hardware or operating system. A virtual machine described by this paper is specified specially for iRTOS which is designed and developed for small-memory embedded applications. Our VM considers size, portability, computing powers, memory consumption, and security. But these considerations have a trade-offs. For example, simple implies slow and fast implies more critical, less portable and larger memory consumption. Our VM has a five essential components ― class loading sytem, interpreter and excution stack, thread and thread system, internal structures, and memory system and garbage collector. It excludes verifier, compiler, and native interface which are designed and implemented soon by other laboratory collegues. We learns a lot of knowledges about networking, Java™ language, C language, RTOS, Java™ platform, principal of Java™ API, and graphic user interface through this study. But we have to suggest algorithms and mechanisms that raise computing powers and portabilities of VM, and also design and implement KNI, compile, and Jini for middle ware application programmers.

실시간 운영체제 환경에서 FAT 파일 시스템의 성능 분석

이호송 충남대학교 대학원 2005 국내석사

Due to the development of hand-held computers and the wide spread of personal information devices, the era of ubiquitous computing has come, and embedded system has become interesting among people all around the world. As embedded system has been applied to a variety of fields, several functions such as networking, multi-media processing, supporting various file systems, and so on have been demanded in it. In this thesis, Embedded FAT File System is implemented with the concept of virtual file system applied in order to support various file systems. Virtual file system enables this Embedded FAT File System to provide the same interfaces for the user layer, and all kinds of FAT file systems are also supported by Embedded FAT File System. The file system implemented in this thesis has been applied in the embedded system, which consists of ARM9™-based SAMSUNG™ S5H5002 DVD processor. The fact that the performance of this Embedded FAT File System is mainly influenced by disk I/O is identified through the performance analysis. Therefore, to improve the performance of this file system, it is most important to reduce the number of disk I/Os with an efficient buffering method. In this thesis, the method of separating a buffer into two parts, one for the file allocation table area and the other for the data area, is proposed for better performance of this file system. With this method, hit ratio can be raised when the total size of buffer is small. Consequently, the performance can be improved in the embedded system, which has the limited size of memory.

32-bit CPU를 기반으로 한 제어계측용 내장형 시스템 개발

全永南 단국대학교 2001 국내석사

정밀한 계측을 위해서는 우선 실험대상의 특성에 맞도록 제어계측 시스템을 구성하여야 한다. 또한 구축된 시스템이 실험의 특성을 정확하게 분석하고, 목적에 올바르게 활용될 수 있도록 운용되어야만 신뢰성 있는 시험이 가능하다. 본 논문에서 연구한 시스템은 각종 센서로부터 들어오는 신호의 고속처리 및 응답을 통하여 동적인 제어가 되도록 개발 되었다. 실험하는 목적에 따라 채널수가 가변적인 점을 고려하여 확장성 있는 하드웨어를 개발하고, 제어와 계측을 동시에 하기 위하여 이에 맞는 펌웨어를 개발했다. 개발된 시스템은 차축 부하시험기에 적용하여 우수한 결과를 확인했다. 기존의 16-bit 마이크로 프로세서는 처리속도가 늦어서 실시간 처리가 불가능하다. 이 문제를 해결하기 위하여 32-bit 마이크로 프로세서를 채택하고, 실시간 운영체재(Real Time Operating System ; RTOS)를 탑재하여 실시간 처리의 구현이 가능하게 되었다. 이러한 32-bit 내장형 시스템(embedded system)이 성공하기까지에는 본인이 근무하고 있는 회사연구팀과의 3 년여에 걸친 연구기간과 많은 개발예산이 투자되었다. 본 논문은 차축부하시험기에 적용된 사례를 통하여 내장형 하드웨어 장치의 개발방법을 제시한다. 특히 다중처리 기능을 이용한 펌웨어를 사례로 제어계측을 위한 32-bit 내장형 시스템의 개발방안을 모색하였다. In order to precise measuring, a control and measuring system should be suited with test specimen's characteristics. Also it is possible to precise testing under completely understanding by analyzing for specimen's characteristics and executed with accurate test object. In the thesis, the system has developed dynamic control through high speed processing and responding of input signal from variety sensors. Which have variable channel numbers according to testing purpose. And has developed firmware for control and measure at real time. We have confirmed good results that we applicants on Axle Dynamometer, which was accomplishment. It is impossible to do work on real time using 16-bit microprocessor, because of processing time is not enough fast. So, we have using 32-bit microprocessor to clear this trouble. And we can processing on real time using RTOS(Real Time Operating System). To get in success with 32-bit embedded system, Research and Development team's efforts and capital investments of my company during last 3 years. This thesis that represented developing of embedded system through application of Axle Dynamometer. Especially, we draw up a firmware using multi-tasking functions as developing example of 32-bit embedded system for control and measurement.

디지털 컨버전스 기기를 위한 파일 시스템 설계 및 구현

정근재 충남대학교 대학원 2008 국내석사

This paper deals with Design and Implementation of a File System for digital convergence devices. Due to the growth of embedded systems and the development of semi-conductor and storage devices, digital convergence devises is ever growing. Digital convergence devices are equipments into which various functions such as communication, playing movies and wave files and electronic dictionaries are integrated. Example are portable multimedia players(PMPs), personal digital assistants(PDAs), and smart phones. Therefore, these devices need an efficient file system which manages and controls various types of files. In designing such file systems, the size constraint for small embedded systems as well as performance and compatibility should be taken into account. In this paper, we suggest the partial buffer cache technique. Contrary to the traditional buffer cache, the partial buffer cache is used for only the FAT meta data and write-only data. And this paper, we also suggest using Flag for Light-weight File System and using FTL, FAT File System for compatibility. Simulation results show that we could enhance the write performance more than 30% when the file size is larger than about 100 KByte.

실시간 운영체제에 기초한 범용 로봇 제어 환경의 구현

이덕만 포항공과대학 1992 국내석사

TMO 모델 기반 무인자동차 제어 시스템 설계 및 구현

이근수 건국대학교 대학원 2008 국내석사

The accurate response time in a real-time system is necessity. Research on guaranteed response time is still an important issue. The TMO(Time-triggered Message-triggered Object) structuring scheme, invented by Professors Kane Kim and Hermann Kopetz, aims at supporting the guaranteed response time of a target real-time system in design stage. TMOSM/Linux has developed to support the execution of TMO structured programs on Linux at the RTSE lab. In the Konkuk University[1, 2, 3, 4]. The embedded system is applied today in various fields. Seeing as systems center to become actual common use, the system comes to divide into a signal process system, mission critical system, distributed control system. UGV(Unmanned Ground Vehicles) control system belongs in a mission critical system[10, 11, 12, 13]. TMO middleware with linux operating system based on open source instead of using the real-time operating system setup of the high price to control UGV in this paper. Design and implement the UGV control system which has the reliability and strength of a height performance.

전력감시 제어시스템의 유도전동기 고장진단 및 디지털계전기 고장 보호를 위한 지능형기법 연구

이성환 연세대학교 1997 국내박사