从结构上来说，实时多任务操作系统包括两部分，一部分为操作系统内核(kernel)，即实时执行程序(Real Time Executive:RTX)，另一部分是输入输出部分(I/O)(注意开发系统不属于操作系统的范畴)；嵌入式系统对I/O的需求通常比较小(无文件系统需求)，因此很多实时多任务操作系统本质上就是一个实时执行程序，如AMX(Kadak)，VRTX(Microtec)，iRMX(Intel)等(这里的X即:eXecutive)，如果纯粹从kernel的角度来考察目前流行的各种实时多任务操作系统的性能，它们的效率差别都不大。 在市面上可以得到一些RTX的源代码(有用C实现的，有用汇编实现的，还有用PL/M语言实现的)，从internet上也可以荡一些下来(我介绍一个站点www.eg3.com，堪称世界电子工程师资源宝库)，下面我要介绍的一个RTX版本(我命名为SRTX:short RTX)，可以说是RTX中的元老级产品了，来自某研究所，九十年代初他们到美国考察，从美国某公司购得。五年以前，SRTX在国内有售，许多搞工控的研究所利用SRTX开发了一些大型或小型的产品,这里介绍的SRTX我作了一些简化和改动.
标签：
上传时间： 2015-12-09
上传用户：wang5829
Abstract: By using gateway systems on large 32-bit platforms, networks of small, 8- and 16-bit microcontrollers can be monitored and controlled over the Internet. With embedded Linux, these gateways are easily moved from full-blown host PCs to embedded platforms like the PC104. In this class you will learn about hardware platforms that support embedded Linux, Linux kernel configuration, feature selection, installation, booting and tuning.
标签： bit platforms Abstract networks
上传时间： 2014-01-05
上传用户：kytqcool
In a preemptive priority based RTOS, priority inversion problem is among the major sources of deadline violations. Priority inheritance protocol is one of the approaches to reduce priority inversion. Unfortunately, RTOS like uC/OS can’t support priority inheritance protocol since it does not allow kernel to have multiple tasks at the same priority. Although it has different ways to avoid priority inversion such as priority ceiling protocol, developers still have some difficulties in programming real time applications with it. In this paper, we redesign the uC/OS kernel to provide the ability to support round robin scheduling and implement priority inheritance semaphore on the modified kernel. As result, we port new kernel with priority inheritance semaphore to evaluation board, and evaluate the execution time of each of the kernel service as well as verify the operations of our implementation.
标签： priority preemptive inversion problem
上传时间： 2015-12-14
上传用户：气温达上千万的
基于ecos的redboot，该包支持多种处理器。用户可以根据自己硬件平台，通过ecosconfig来配置，配置界面和编译linux kernel差不多。本包已经正对Intel IXP2400平台做了相应配置，硬件平台为双CUP架构。压缩文件中有更为详细的说明。
上传时间： 2014-01-09
上传用户：siguazgb
java语言开发的P2P流媒体系统，“Stream-2-Stream implements multicast+, a next generation streaming protocol. Multicast+ is more efficient and requires less bandwidth than direct streaming (e.g. shoutcast/icecast). Stream-2-Stream (abbreviated "s2s" or "S2S") stations have no user limit stations can be set up without paying a fortune for bandwidth. Stream-2-Stream saves bandwidth by passing streams from one peer to another through multicast and unicast p2p, rather than everyone getting a stream from one central server (Shoutcast/Icecast). ”更多：http://s2s.sourceforge.net/about.php
上传时间： 2016-01-09
上传用户：ikemada
嵌入式Linux 内核移植相关代码分析 本文通过整理之前研发的一个项目(ARM7TDMI +uCLinux)，分析内核启动过程及需要修改的文件，以供 内核移植者参考。整理过程中也同时参考了众多网友的帖子，在此谢过。由于整理过程匆忙，难免错误 及讲解的不够清楚之处，请各位网友指正，这里提前谢过。本文分以下部分进行介绍： 1. Bootloader 及内核解压 2. 内核启动方式介绍 3. 内核启动地址的确定 4. arch/armnommu/kernel/head-armv.S 分析 5. start_kernel()函数分析
标签： ARM7TDMI uCLinux Linux 嵌入式
上传时间： 2016-01-12
上传用户：xzt
Linux 2.4.18 s3c2440 led driver 使用dev-C++撰寫，需要linux 2.4.18 kernel include，編譯完成後產生led module。 insmod main.o //安裝模組 mknod /dev/leds c 221 0 使用方法： int main(int argc, char *argv[]) { int testdev //led test... testdev = open("/dev/QuickMarkLed",O_RDWR) ioctl(testdev, 2, 1) //ioctl(device, led number, open/close) open=1 ioctl(testdev, argv[1][0]- 0 , argv[2][0]- 0 ) //ioctl(device, led number, open/close) open=1 close(testdev) return 0 }
标签： s3c2440 driver Linux dev-C
上传时间： 2014-01-01
上传用户：qlpqlq
This m-file simulates MPSK (BPSK,QPSK,8PSK)with theoretical and simulated results using Gray coding. Numerical examples of a satellite link design are shown using QPSK and/or 8PSK when the bit rate(Rb)is greater than the channel bandwidth Wc (Band-limited channel).
标签： theoretical simulates simulated results
上传时间： 2016-01-19
上传用户：pompey
FIST可堆叠文件系统，linux文件系统修改相关的开源软件，使得对linux文件系统功能的改进很简单了 The FiST (File System Translator) system combines two methods to solve the above problems in a novel way: a set of stackable file system templates for each operating system, and a high-level language that can describe stackable file systems in a cross-platform portable fashion. Using FiST, stackable file systems need only be described once. FiST s code generation tool, fistgen, compiles a single file system description into loadable kernel modules for several operating systems (currently Solaris, Linux, and FreeBSD). The project demonstrates that with FiST, code size and development time are reduced significantly, while imposing a small performance overhead of only 1-2％. These benefits are achieved, as well as portability, without changing existing operating systems or file system.
上传时间： 2014-01-10
上传用户：xsnjzljj
from wangkj@yahoo.com 电路原理图和详细说明： amd.9966.org或者 arm.9966.org 都是原创,包括boot, loader,u-boot,linux 和测试程序 这些都是针对那个网站板子的配套程序，板子可以按照该网站提供的联系方式联系获取 这是和boot,loader,配套的u-boot程序。 关于kernel，超过100M，不能上传。
上传时间： 2016-01-31
上传用户：我干你啊
