stevenliyong 的专栏

原创 stack type, full-ascending, full-descending, empty-ascending, empty-descending

Stack Types. Since it is left to the software to implement a stack, different implemenation choices result different types of stacks. There are two types of stack depending on how the stack grows.

原创 ARM GCC linker 脚本介绍

1. Referencearm-2011.03/share/doc/arm-arm-none-eabi/pdf/ld.pdf2. An exampleOUTPUT_FORMAT ("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")/* Use OUTPUT_FORMAT with three arg

转载 Setting up a GCC Development Environment for the Cortex M0/M3

http://www.microbuilder.eu/projects/LPC1343ReferenceDesign/LPC1343Toolchain.aspxSetting up a GCC Development Environment for the Cortex M0/M3Tutorial on installing all everything needed

原创 P4 使用

p4 loginp4 -p 10.21.0.3:1999 sync -f //depot/sw/branches/olca/...#headp4 edit xxxx.cmodify or patch -p4 p4 diff -du  p4 revert ...

原创 windows 环境下 scons 交叉编译 （RVCT4.1）

1. Install python2.7 和 scons将环境变量 c:/Python2.7 和 c:/python2.7/scripts 加到 PATH2. sconstruct 文件 显示继承 所有windows 环境变量Or you may expl

转载 调频 预加重 和 去加重 （FM Pre-emphasis/De-emphasis）

理论已经证明,鉴频器的输出噪声功率谱按频率的平方规律增加。但是，许多实际的消息信号，例如语言、音乐等，它们的功率谱随频率的增加而减小，其大部分能量集中在低频范围内。这就造成消息信号高频端的信噪比可能降到不能容许的程度。但是由于消息信号中较高频率分量的能量小，很少有足以产生最大频偏

原创 dash 和 bash

1.Bash is the shell, or command language interpreter, that will appear in the GNU operating system. Bash is an sh-compatible shell that in

转载 使用 SCons 轻松建造程序

转自 http://www.ibm.com/developerworks/cn/linux/l-cn-scons/index.html?ca=drs-简介： 在软件项目开发过程中，make 工具通常被用来建造程序。make 工具通过一个被称为 Ma

转载 what is difference between IRQ and FRQ

http://www.allinterview.com/showanswers/96317.htmlCPU is a sequentially executing machine. It will execute theinstructions fr

转载 I2C Bus

http://baike.baidu.com/view/751581.html?goodTagLemma

转载 There's Much More than Intel/AMD Inside

http://www.tensilica.com/markets/pcs-ntbks-printers.htmThere's Much More than Intel/AMD InsideWhile the main CPU in a personal or notebook c

转载 集成电路 RTL 设计

转载 TI DaVinci(达芬奇)入门

（转载来自 德州仪器半导体技术（上海）有限公司 通用DSP 技术应用工程师 崔晶    德州仪器（TI）的第一颗达芬奇（DaVinci）芯片（处理器）DM6446已经问世快三年了。继DM644x之后，TI又陆续推出了DM643x，DM35x，DM6467，OMAP353x等一系列

转载 Network Analysis With Wireshark On Ubuntu 9.10

http://www.howtoforge.com/network-analysis-with-wireshark-on-ubuntu-9.10

原创 802.11 Four-way handshake Messages

1.  4-way handshake sequence2. Key HeirarchyThe EAPOL encryption key is the middle 128 bits of the PTK value.  And the first 128 bits of the

转载 AES算法分析与实现

AUTHOR:   Jeffrey.zhu                                    BLOG：http://blog.csdn.net/gueter/       AES算法的主要数学基础是抽象代数，其中算法中的许多运算是按单字节（8bits）和4字

原创 IEEE 802 LAN/MAN Standards Committee

http://www.ieee802.org/

转载 802.11ac and 802.11ad

IEEE正在全面制定802.11ac标准工作。IEEE预测，将会在2011年11月完成对802.11ac和802.11ad标准的制定，而到2012年12月将会放出正式的版本。802.11ac项目早在2008年上半年就已经着手开始，当时被称为“Very High

原创 Wireless Ad-Hoc Network – Linux

转自 http://mohan43u.wordpress.com/2010/01/31/wireless-ad-hoc-network-linux/  Long time back, I actually did peer-to-peer with RJ232 connector using mine and my friend’s laptops. Its really

原创 RTS/CTS协议 （Both wlan and com are using it）

　　RTS/CTS协议(Request To Send/Clear To Send)即请求发送/允许发送协议，相当于一种握手协议，主要用来解决"隐藏终端"问题。"隐藏终端"（Hidden Stations）是指，基站A向基站B发送信息，基站C未侦测到A也向B发送，故A和C同时将信号发送至B，引起信号冲突，最终导致发送至B的信号都丢失了。"隐藏终端"多发生在大型单元中（一般在室外环境），这将

原创 802.11 Scan and Discovery

 802.11MAC层负责客户端与AP之间的通讯。主要功能包括：扫描、接入、认证、加密、漫游和同步。802.11MAC报文分类：   ---数据帧      用户的数据报文   ---控制帧       协助发送数据帧的控制报文，例如：RTS、CTS，ACK等   ---管理帧       负责STA和AP之间的能力级的交互，认证、关联等管理工作，例如：  

转载 Wifi Connection

1. Connection Establishment using WEP  2. Connection establishment using WPA3. Connection establishment using 802.11i (WPA2)  

转载 Wireless Operating Modes

http://linuxwireless.org/en/users/Documentation/modes A wireless interface always operates in one of the following operating modes. The mode sets the main functionality of the wireless link. 

转载 Open System authentication

Open System authenticationOpen System authentication is a null authentication algorithm. Any STA requesting Open Systemauthentication may be authenticated if dot11AuthenticationAlgorithm at the

转载 802.11 Authentication and Association

The 802.11 standard provides a method for supplying different levels of access to different nodes in a wireless local area network (WLAN). This is handled through authentication and association. Eac

转载 The Four-Way Handshake

 The authentication process leaves two considerations: the access point (AP) still needs to authenticate itself to the client station (STA), and keys to encrypt the traffic need to be derived. The e

原创 Use ADB to connect phone with Windows 7 over tcp

<br /><br />> adb.exe connect 192.168.0.12:5555<br />* daemon not running. starting it now on port 5037 *<br />* daemon started successfully *<br />connected to 192.168.0.12:5555<br /> <br />> adb.exe shell<br /> <br />Ps: adb.exe is under android-sdk-wind

转载 A successful Git branching model

<br />By http://nvie.com/posts/a-successful-git-branching-model/<br /> <br /><br />In this post I present the development model that I’ve introduced for all of my projects (both at work and private) about a year ago, and which has turned out to be very suc

原创 Increase the android VM heap size.

<br /> <br /> <br />It is very easy , in init.rc<br />add line<br />setprop dalvik.vm.heapsize 48m

原创 file lock in the Linux system

<br /> <br />1. Use the flock in the shell script,<br /> <br />http://linux.die.net/man/1/flock<br /> <br />2. Use flock in code<br />http://linux.die.net/man/2/flock<br /> <br />My sample.<br /> <br /> int fd = open("/data/misc/wifi_lock", O_RDWR|O_CREAT,

转载 Timestamping Linux kernel printk output in dmesg for fun and profit

<br />转自：<br />http://www.digitalprognosis.com/linuxtips/timestamping-linux-kernel-printk-output-in-dmesg-for-fun-and-profit/<br /> <br /> <br /> <br /><br />Timestamps are a wonderful thing. When you have systems with an uptime of hundreds of days or more

原创 ANDROID LINUX KERNEL ADDITIONS

<br />http://www.lindusembedded.com/blog/2010/12/07/android-linux-kernel-additions/

原创 ANDROID LINUX KERNEL ADDITIONS

<br />http://www.lindusembedded.com/blog/2010/12/07/android-linux-kernel-additions/

转载 HOWTO: Booting from SD card using U-Boot

<br />转自：http://bill.station51.net/index.php?post/2010/01/30/HOWTO%3A-Booting-from-SD-card-using-U-Boot<br /> <br /><br />Many many people want to know how to boot their Mini2440 or Micro2440 off of an SD card and I'm going to show you how.<br />For this t

转载 HOWTO: Booting from SD card using U-Boot

<br />转自：http://bill.station51.net/index.php?post/2010/01/30/HOWTO%3A-Booting-from-SD-card-using-U-Boot<br /> <br /><br />Many many people want to know how to boot their Mini2440 or Micro2440 off of an SD card and I'm going to show you how.<br />For this t

转载 Linux initial RAM disk (initrd) overview

<br />http://www.ibm.com/developerworks/linux/library/l-initrd.html<br /> <br /> <br /><br />What's an initial RAM disk?<br />The initial RAM disk (initrd) is an initial root file system that is mounted prior to when the real root file system is available.

转载 Detecting Memory Leaks in Kernel

<br /> <br />This doc is from<br />http://psankar.blogspot.com/2010/11/detecting-memory-leaks-in-kernel.html<br /> <br /> <br />A memory leak is a behavior of a program when it consumes memory but never releases it. In user-space, these days, new applicati

原创 How to make SD Card world wide writable

<br /> <br /><br />Add the followling property to the init.rc<br /> <br /> <br /># Make SD Card world wide writable<br />    setprop persist.sampling_profiler 1

转载 Build GingerBread on 32 bit machine.

I tried and it works http://forum.xda-developers.com/showpost.php?p=9998281&postcount=12A quick and brutal fix is to:1) go to gingerbread/prebuilt/linux-x86/toolchain2) rename arm-eabi-4.4.3 to arm-eabi-4.4.3.old3) link arm-eabi-4.4.0 to arm-eabi-4.4.3Code

原创 Netconsole to capture the log

<br />1. Netconsole Server Machine <br />#export TARGET_IP_ADDR=XX:XX:XX:XX<br />#export TARGET_MAC_ADDR=XX:XX:XX:XX<br />#modprobe netconsole netconsole=@/eth0,9999@$IP_ADDR/$MAC_ADDR<br />#nc -l -p 6777 -c "hcidump -i hci0 -X" &<br />#nc -l -p 6888 -c "h