ACPI介紹

http://blog.csdn.net/celiaqianhj/article/details/6742852

介紹了ACPI的RSDP, RSDT, XSDT ...等等的關係.
整理的很不錯喔.

C-states and P-states are very different

C-states and P-states are very different

C-states are idle states and P-states are operational states. This difference, though obvious once you know, can be initially confusing. 

With the exception of C0, where the CPU is active and busy doing something, a C-state is an idle state. Since an idle CPU isn't doing anything (i.e. any useful work), why not shut it down? No one is going to notice since there's no one using it. (Letting a Penryn run at full bore when idle is like driving in circles very fast; all you're doing is going nowhere quickly.)

A P-state is an operational state, meaning that the core / processor can be doing useful work in any P-state. The most obvious example is when your laptop is using a low power profile and operating on battery. The OS will lower the C0 operating frequency and voltage, i.e. enter a higher P-state. Reducing the operating frequency reduces the speed at which the processor operates, and so the energy usage per second (i.e. power). Reducing the voltage decreases the leakage current from the CPU's transistors, making the processor more energy efficient resulting in further gains. The net result is a significant reduction in the energy usage per second of the processor. On the flip side, an application will take longer to run. This may or may not be a problem from a power perspective. I'll talk about this issue in some depth in a later blog.

C-states and P-states are also orthogonal. This is a fancy mathematical term meaning that each can vary independently of the other. This doesn't mean that in the higher C-states, the voltage doesn't change. It only means that when you resume C0, you go back to the operating frequency and voltage defined by that P-state. 

Linux Plumbers Conference

突然發現這個, 記錄一下 http://www.linuxplumbersconf.org

Linux Plumbers Conference 2012 Videos & Slides
http://www.linuxplumbersconf.org/2012/

USB Port Power Off Kernel/User Space
http://linuxplumbers.ubicast.tv/videos/usb-port-power-off-kerneluserspace-api/

有趣的專利

今天看到2個專利的討論, 記錄一下

(1)電子工程專輯的 醬也行？－－有趣“瘋狂專利”分享
原始來源:What were they thinking: Confessing to an apparition

(2)Cash's Blog的UIBC小註解
UIBC 是指 User Input Back Channel，用在 WIFI Display 的情境之下. 由於顯示裝置 (AV sink device) 和發送裝置 (AV source device) 只能透過無線傳輸，所以從顯示裝置反過來操作發送裝置的話，就叫做 UIBC。
Samsung的專利 Method and apparatus for providing user input back channel in audio/video system
專利公開:US20110107388 A1

ctags在vim裏的常用操作

最近又開始想用vim+ctags功能了, 紀錄一下常用的快速指令囉!

ctags in vim

Keyboard	Command Action
Ctrl-] 或是 Ctrl-Left_MouseClick	跳到tag所定義的地方
Ctrl-t 或是 Ctrl-Right_MouseClick	返回
:ts <tag>  <RET>	Search for a particular tag
:tn	Go to the next definition for the last tag
:tp	Go to the previous definition for the last tag
:ts	List all of the definitions of the last tag

cscope_maps.vim plugin

這邊的用法是Ctrl+\按完後, 全放開, 再去按後面的字母

ctrl+\ s    "s表Symbol，列出所有參考到游標所在字串的地方，包含定義和呼叫。

ctrl+\ g    "g表Global，與ctags的Ctrl+]相同。

ctrl+\ c    "c表Caller，列出所有會呼叫到以游標所在字串當函數名的地方。

ctrl+\ t     "t表Text，列出專案中所有出現游標所在字串的地方。

ctrl+\ f     "f表File，以游標所在字串當檔名，開啟之。

ctrl+\ i     "i表Include，以游標所在字串當檔名，列出所有include此檔的檔案。

ctrl+\ d    "d表calleD，以游標所在字串當函式名，列出所有此函式內呼叫的函式。

在使用cscope時，需注意，cscope.out這個資料庫是否有被connect起來，如果沒有connect那搜尋功能當然就會失效。
發現一件事情，ctags的關聯都是用絕對路徑的，所以就算我任意切目錄，只要database有認到就沒問題。
但是cscope看起來是不行的，它用相對路徑的，一切目錄，就算database認到了，看起來也開不了檔案。

Vim 快速指令
在command mode底下(不用打:)
gf (goto file)
  比如:當你的游標停在#include , 此時直接打gf, 就會自動幫你開啟該header file
  先決條件是,你必需先指定好path, 參考方法是":set path=include;/usr/include"
  當你要返回時,使用ctrl+o返回
* 搜尋字串
  游標停在你要尋找的字串上,直接按shift+8(相當於按*),
  然後就可以用n往下搜尋,按N往上搜尋了
gd 查區域變數, gD查全域變數
  追蹤某個變數宣告時,可以用gd或gD去跳轉
% 括號跳轉
  有時function非常的長, 每次都要用page up/down一直換頁, 還要擔心跳過頭
  %可以幫你直接跳到左括號或右括號上, 也適用於C的#def喔.
  當然, 同樣的你要先把游標移到括號上喔.
mx及'x   標記及返回
          你可以在任意地方標記該行, 然後亂跑後, 再打'x來返回剛剛標記的地方

Linux Trace Tool Introduction

OpenPCR 開放原始碼的基因定序儀

OpenPCR 開放原始碼的基因定序儀 - 
OpenPCR is a low-cost, yet accurate thermocycler you build yourself, capable of reliably controlling PCR reactions for DNA detection, sequencing, and other applications.
一台美金599元

PCR (Polymerase chain reaction聚合酶鏈鎖反應), 複製已知的DNA片斷來作相關的基因研究。
因此OpenPCR 是一台便宜用來複製 DNA 的機器，我們可以將採集到微量DNA，用OepnPCR複製之後，拿來診斷疾病，也可以用來判斷食品是否有受污染，或者檢查食品是否有使用基因改造作物。

新潮玩法：家庭基因实验室

論壇 不過這個論壇似乎很久沒更新了.

GitHub OpenPCR Source Code Project 

基隆米克斯公司的PCR說明

[試劑耗材]基本分生技術介紹 PCR Cloning - 分生實驗的必經之路

簡伯容 博士 - PCR 技術簡介
長庚微免所 劉世東 教授 - 進行 PCR 反應時的注意事項

Hate Brussels Sprouts? It's Genetic - Pearl Biotech's Open PCR Project

How to do a PCR

PCR Procedure

PCR介紹

看日記學Git

看日記學Git from stenly ho