Power over Ethernet (PoE) is a new development thatallows for the delivery of power to Ethernet-based devicesvia standard Ethernet CAT5 cable, precluding the need forwall adapters or other external power sources. The PoEspecification defines a hardware detection protocol wherePower Sourcing Equipment (PSE) is able to identify PoEPowered Devices (PDs), thus allowing full backwardscompatibility with non-PoE-aware (legacy) Ethernetdevices.
This ink marks LTC’s eighth circuit collection publication.1We are continually surprised, to the point of near mystification, by these circuit amalgams seemingly limitlessappeal. Reader requests ascend rapidly upon publication,remaining high for years, even decades. All LTC circuitcollections, despite diverse content, share this popularity,although just why remains an open question. Why isit? Perhaps the form; compact, complete, succinct andinsular. Perhaps the freedom of selection without commitment,akin to window shopping.
針對科研實驗中對拉壓千斤頂加載過程控制的需要，采用ATmega128單片機控制步進電機進而實現對執行系統的電動泵站實行自動控制。對力和位移的數據采集與處理及用步進電機控制電動泵站手柄的技術細節作了重點描述。通過單片機的A/D變換器對AMP放大模塊采集的電橋信號作量化處理，千斤頂的操控手柄位置依電動油泵閥門開啟的方向和大小作若干定位，單片機根據力或位移傳感器信號，實時控制步進電機驅動手柄旋轉到相應操控位置。
Abstract:
This article describes the use of ATmega128 AVR microcontroller series of DBS electric pumping stations and QF100/200 separate twoway hydraulic jack to automate the process of manipulating the work of the technical content. Articles on force and displacement data acquisition and processing， and stepper motor control electric pump with the handle of the key technical details were described. Through the MCU’s A / D converter module is collected on the AMP amplification quantify the signal bridge， jack handle position control valve opening according to the direction of electric pumps for a number of positioning and size of the microcontroller based on force or displacement sensor signals， real-time control stepper motor drive control handle rotate to the appropriate location.
在需要實時大量輸入漢字的顯示控制處理應用中，利用傳統單片機實現顯示控制的設計方法是較難實現的。帶漢字字庫的液晶模塊的使用使得小容量ROM單片機的大量漢字信息輸入與顯示成為可能。提出了針對漢字字庫編碼的二級索引拼音輸入檢索方法,介紹了以ST7920作為控制器的帶漢字字庫的液晶顯示模塊的接口方法及漢字顯示和控制原理，給出了通用計算機鍵盤在單片機中的串行接口，采用該技術可大大增強單片機的漢字輸入功能。為小容量ROM單片機的大批量漢字信息處理提供了一種漢字輸入解決方案。
Abstract:
It is difficult to realize Chinese characters input method based on the embedded system by using the traditional design method of display control. It is possible to input and display Chinese characters based on the embedded system with the ROM of small content by using the LCD module with Chinese characters.Chinese characters input method of the quadric index recall in allusion to Chinese characters code is brought forward.The interface and the principle of Chinese characters display control based on the LCD module controlled with the ST7920 is introduced too.The serial interface of the computer keyboard in common use and the embedded system is given at the same time. It can enhance the embedded system function of Chinese characters input by using this technology, and provide a kind of Chinese characters input scheme for the embedded system with small capacity ROM.
The Philips family of Multiplexers and Switches consists of bi-directional translating switches controlled via the I2C or SMBus to fan out an upstream SCL/SDA pair to 2, 4 or 8 downstream channels of SCx/SDx pairs. The Multiplexers allow only one downstream channel to be selected at a time, while the Switches allow any individual downstream channel or combination of downstream channels to be selected, depending on the content of the programmable control register. Once one or several channels have been selected, the device acts as a wire, allowing the master on the upstream channel to send commands to devices on all the active downstream channels, and devices on the active downstream channels to communicate with each other and the master. External pull-up resistors are used to pull each individual channel up to the desired voltage level. Combined interrupt output and hardware reset input are device options that are featured.
Agilent AN 154 S-Parameter Design Application Note S參數的設計與應用
The need for new high-frequency, solid-state circuitdesign techniques has been recognized both by microwaveengineers and circuit designers. These engineersare being asked to design solid state circuitsthat will operate at higher and higher frequencies.The development of microwave transistors andAgilent Technologies’ network analysis instrumentationsystems that permit complete network characterizationin the microwave frequency rangehave greatly assisted these engineers in their work.The Agilent Microwave Division’s lab staff hasdeveloped a high frequency circuit design seminarto assist their counterparts in R&D labs throughoutthe world. This seminar has been presentedin a number of locations in the United States andEurope.From the experience gained in presenting this originalseminar, we have developed a four-part videotape, S-Parameter Design Seminar. While the technologyof high frequency circuit design is everchanging, the concepts upon which this technologyhas been built are relatively invariant.The content of the S-Parameter Design Seminar isas follows:
PhpDig is a search engine written in PHP that uses a MySQL database backend. It features indexing of both static and dynamic pages, spidering of almost all links in HTML content, in hrefs, areamaps, and frames, and full text indexing. The search results appearence is skin-able, using a very simple templates system. PhpDig是一個用PHP編寫的搜索引擎，它使用MySQL數據庫后臺。它的功能有靜態和動態頁面索引，在HTML內容中用hrefs, areamaps，和frames以及全文本索引構成所有的鏈接網。搜索結果的外觀是可定制外觀的，使用一個非常簡單的模板系統。
ngrep strives to provide most of GNU grep s common features, applying them to the network layer. ngrep is a pcap-aware tool that will allow you to specify extended regular or hexadecimal expressions to match against data payloads of packets. It currently recognizes TCP, UDP and ICMP across Ethernet, PPP, SLIP, FDDI, Token Ring and null interfaces, and understands bpf filter logic in the same fashion as more common packet sniffing tools, such as tcpdump and snoop.
