摘要 本研究計劃之目的，在整合應(yīng)用以ARM為基礎(chǔ)的嵌入式多媒體實時操作系統(tǒng)于H.264/MPEG-4多媒體上。由于H.264是一種因應(yīng)實時系統(tǒng)(RTOS)所設(shè)計的可擴展性串流傳輸(scalability stream media communication)的編碼技術(shù)。H.264主要架構(gòu)于細(xì)細(xì)粒可擴展(Fine Granula Scalability,FGS)的壓縮編碼機制。細(xì)粒度可擴展壓縮編碼技術(shù)是最新MPEG-4串流式傳輸標(biāo)準(zhǔn)，能依頻寛的差異來調(diào)整傳輸?shù)姆绞健＜?xì)粒度擴展縮編碼技術(shù)以編入可選擇性的增強層(enhanced layers)于碼中，來提高影像傳輸?shù)馁|(zhì)量。本計劃主要在于設(shè)計一種簡單有效的實時階層可擴展的影像傳輸系統(tǒng)。在增強層編碼及H.264的基本層(base layer)編碼上使用漸進(jìn)的細(xì)粒度可擴展編碼(Progressive Fine Granularity Scalable,PFGS)能直接使用H.264的格式特色來實現(xiàn)FGS。同時加入了LB-LLF(Layer-Based Least-Laxity-Fir stscheduling algorithm)的排程算法，來增 進(jìn)網(wǎng)路傳輸影像的質(zhì)量。由實驗結(jié)果顯示本系統(tǒng)在串流影像質(zhì)量PSNR值上確有較佳的效能。
標(biāo)簽： 芯片系統(tǒng) 架構(gòu) 開發(fā)平臺
上傳時間： 2014-12-26
上傳用戶：mpquest
提出了一種以S3C2440A為核心處理器的銀行評價器的設(shè)計方案，并結(jié)合XILINX公司的XL95144XL型CPLD，輔助S3C2440A，實現(xiàn)該銀行評價器的各部分功能以及系統(tǒng)信號之間的相互協(xié)調(diào)。該評價器在系統(tǒng)設(shè)計上采用液晶屏顯示，代替了以往簡單的數(shù)碼管電路的顯示模式，在視覺上給人以全新的享受。同時，評價器增加了新的網(wǎng)絡(luò)供電方式，只要將評價器連接上網(wǎng)絡(luò)就可以正常工作，方便了客戶的使用。總之，此款銀行評價器采用了嵌入式系統(tǒng)的設(shè)計方案，大大豐富了系統(tǒng)功能，實現(xiàn)一個銀行評價器設(shè)計的新突破。 Abstract: S3C2440A of SamSung company is the core component of the embedded system. A design of bank assessor based on S3C2440A was provided in this paper. It used XL95144XL combined with S3C2440A to realize all the functions and coordination with system signals. This bank assessor used LCD to display instead of the former simple digital display and provided a new seusuous enjoment. Meanwhile，it provided a new method of network power supply，that the bank assessor could regularly work once it connected to the network，which is convenient for customers to use. In a word，this assessor takes embedded system，enriches the system’s functions and reclizes a new breakout.
標(biāo)簽： S3C2440A
上傳時間： 2013-11-03
上傳用戶：taa123456
為提高電容測量精度，針對電容式傳感器的工作原理設(shè)計了基于PIC16LF874單片機電容測量模塊。簡單闡述了電容測量電路的應(yīng)用背景和國內(nèi)外研究現(xiàn)狀，介紹了美國Microchip公司PIC16LF874單片機的特性。電容式傳感器輸出的動態(tài)微弱電容信號通過PS021型電容數(shù)字轉(zhuǎn)換器把模擬量數(shù)據(jù)轉(zhuǎn)換成數(shù)字量數(shù)據(jù)，所測數(shù)據(jù)由PIC16LF874單片機應(yīng)用程序進(jìn)行處理、顯示和保存。實驗結(jié)果表明，固定電容標(biāo)稱值為10~20 pF 的測量值相對誤差在1%以內(nèi)，同時也可知被測電容容值越大，測量值和標(biāo)稱值相對誤差越小。 Abstract: To improve the accuracy of capacitance measurement，aimed at the principle of work of mercury capacitance acceleration transducer，the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers，focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of weak PS021-chip capacitors （capacitancedigital converter） to convert analog data into digital data，the measured data from the PIC16LF874 microcontroller application process， display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%，but also it canbe seen the value of the measured capacitance larger，measuring value and the nominal value of relative error smaller.
上傳時間： 2013-10-29
上傳用戶：wojiaohs
生活中許多目標(biāo)的高度和水平距離需要進(jìn)行測量。目前主要的測量方法，仍以傳統(tǒng)的皮尺丈量為主，測量效率不高，有時還很不方便，沒有技術(shù)成熟的數(shù)字式測高測距產(chǎn)品。以基本的數(shù)學(xué)方法為理論依據(jù)，利用遙控小車做為載體，采用角度傳感器測量角度、霍爾傳感器測量水平距離等，通過單片機LM3S615進(jìn)行數(shù)據(jù)計算，實現(xiàn)了對待測目標(biāo)物體的高度、水平距離等數(shù)據(jù)的快速、精確和數(shù)字式的測量，高度測量精度可達(dá)99.06%，水平測量精度則可達(dá)98.06%。 Abstract: In our lives， the height and horizontal distance of some goals are needed to be measured. Because the currently used methods are still traditional tape-based measuring methods， and the measuring efficiency is low and inconvenient so some kinds of digital and portable measuring methods or instruments are needed. Based on the basic math theory， this paper designed and manufactured a portable， digital and remote controlled measuring mobile small vehicle， which assembled with angle measuring sensor for angle measurement and Hall sensor for horizontal distance measuring. MCU LM3S615 calculated the height and horizontal distance data gotten from these sensors. The measuring process is simple， the measuring results are more accurate and the measuring efficiency is higher than traditional measure instruments. The accuracy of height and distance measurement can reach 99.06% and 98.06%.
上傳時間： 2013-10-30
上傳用戶：jackandlee
以太網(wǎng)和CAN總線應(yīng)用廣泛，但由于其通信協(xié)議不同，兩種總線器件間無法進(jìn)行數(shù)據(jù)通信，因此，設(shè)計了基于CP2200與C8051F040的以太網(wǎng)總線與CAN總線接口轉(zhuǎn)換電路，并給出部分相關(guān)硬件電路與軟件設(shè)計分析。在保證數(shù)據(jù)完整和協(xié)議可靠的前提下，通過握手協(xié)議和簡化的以太網(wǎng)協(xié)議，不僅實現(xiàn)了以太網(wǎng)數(shù)據(jù)與CAN數(shù)據(jù)的轉(zhuǎn)發(fā)，同時還順利的解決了以太網(wǎng)的高速性與CAN的低速率沖突，以及兩者數(shù)據(jù)包之間的大小不同的矛盾。 Abstract: In the development of actual application， Ethernet and CAN bus are used very extensively. Owing to its various communication protocols， the communicating between two kinds of bus device can’t be carried out. Therefore， in order to solve this problem， the Ethernet-CAN bus interface circuit based on CP2200 and C8051F040 was designed in this paper， and part of the related hardware circuit and software design analysis were given. On the condition of data’s integrity and protocols’reliability， through the handshaking protocols and the simplified the Ethernet protocol， not only the data switching between CAN and Ethernet was realized， but also the differ in velocity and packet size was solved.
標(biāo)簽： C8051F040 CAN 以太網(wǎng) 轉(zhuǎn)換
上傳時間： 2013-10-15
上傳用戶：Ants
提出一種基于凌陽單片機的步進(jìn)電機加減速的控制方法。采用凌陽科技推出的16位結(jié)構(gòu)工控單片機SPMC75F2413A為控制器，由Allegro公司生產(chǎn)的兩相步進(jìn)電機專用驅(qū)動器件SLA7042M構(gòu)成步進(jìn)電機的驅(qū)動電路，在傳統(tǒng)的3段直線加減速控制算法基礎(chǔ)上增加至7段S形曲線加減速過程，控制步進(jìn)電機的啟動和停止。實驗結(jié)果表明，該控制方法克服了直線加減速中不連續(xù)、易造成系統(tǒng)沖擊的問題，整個系統(tǒng)實現(xiàn)柔性控制，電機啟動、停止連續(xù)性能提高30%。 Abstract: The method of controlled stepping motor is referred based on SPMC75F2413A MCU， which adopts the 16 knots SPMC75F2413A MCU as the controller. The special-purpose actuation chip SLA7042M of two stepping motor produced by Allegro Corporation constituted to actuation electric circuit. The purpose of increasing to seven section of S shape curve based on the traditional three sections of straight line is to control the start and stop process of stepping motor. The experimental results show that the control method solves easy to pull-out and overshot problems. The overall system realizes flexible control， and the performance of motor start or stop continuity is increased 30%
標(biāo)簽： 凌陽單片機 步進(jìn)電機 減 控制方法
上傳時間： 2013-12-08
上傳用戶：jiangfire
為提高太陽能的利用率，以ATmega8單片機為控制核心，設(shè)計了一套光電跟蹤與視日運動軌跡跟蹤互補控制的雙軸太陽跟蹤器。該跟蹤器在晴天時，利用光敏電阻采集光強判斷太陽位置,控制步進(jìn)電機實現(xiàn)光電跟蹤；在陰天時，采集時鐘器件PCF8583的時間信息,計算當(dāng)前太陽位置來實現(xiàn)視日運動軌跡跟蹤。實驗表明：該太陽跟蹤器能在不同天氣狀況下對太陽進(jìn)行較準(zhǔn)確地跟蹤，能量接收效率提高了30%，達(dá)到充分利用太陽能的目的。 Abstract: To improve the utilization rate of solar energy，a kind of solar tracking controller which effectively combined the sun angle tracking and photo electric tracking based on ATmega8is designed.In the sunny days，the solar tracking con-troller determines the sun's position by using photosensitive resistances to collect light intensity and control stepper motors to achieve photo electric tracking，n cloudy days，it collects clock chip PCF8583time information to calculate the current position of the sun and achieve the sun angle tracking.Experimental results show the solar tracking controller accurately tracks the sun in different weather conditions，improves received energy efficiency by30%and reaches the purpose of full use of solar energy.
上傳時間： 2013-10-15
上傳用戶：urgdil
設(shè)計一種基于ATmega16L單片機的溫度控制系統(tǒng)，闡述該系統(tǒng)的軟硬件設(shè)計方案。采用模塊化設(shè)計方法，利用增量式PID算法使被控對象的溫度值趨于給定值。實驗結(jié)果表明該系統(tǒng)具有良好的檢測和控制功能。 Abstract: This paper designs a temperature control system based on ATmega16L，describes the hardware and software de－sign scheme of the system，adopts the modularized design method and utilizes the incremental PID algorithm to realize the temperature of controlled device incline to the given value.The experiment result indicates that the system has good detec－tion and control function
上傳時間： 2013-10-09
上傳用戶：stvnash
設(shè)計一種基于P89V51RD2的功率因數(shù)測量儀，采用光電隔離器和專用數(shù)碼管驅(qū)動器。該測量儀是以增強型單片機P89V51RD2為核心，大大簡化系統(tǒng)硬件設(shè)計。而軟件部分采用模塊化設(shè)計思想，采用中值濾波和小數(shù)補償算法，實現(xiàn)功率因數(shù)的高精度測量。實驗測試表明，該功率因數(shù)測量儀測量精度高，運行穩(wěn)定可靠。 Abstract: A power－factor measurement instrument based on P89V51RD2is designed，which uses optical coupler and specific LED drive chip.The power factor measurement instrument uses P89V51RD2as a core of which greatly simplifies the system design.Furthermore，modularization software is developed in detail.The high precision power－factor measuring system is realized by the center value filter and fractional compensation algorithm.Experiments manifests that the power－ factor measurement instrument is high precision，steady and reliable.
上傳時間： 2014-12-27
上傳用戶：CHINA526
首先研究CAN總線和SAE J1939協(xié)議，提出一種基于MC9S12HZ256微控制器的總線式汽車數(shù)字儀表解決方案。詳細(xì)介紹SAE J1939協(xié)議的報文幀格式及應(yīng)用層協(xié)議中發(fā)動機相關(guān)參數(shù)的定義，以及步進(jìn)電機及其驅(qū)動和車速信號的處理方法。該數(shù)字儀表系統(tǒng)硬件平臺由微處理器和信號采集和信息處理及顯示等模塊組成。軟件設(shè)計部分編程實現(xiàn)了對CAN總線和各傳感器數(shù)據(jù)的讀取、處理。該系統(tǒng)能夠?qū)崟r反映車輛工況。 Abstract: In this paper，CAN bus and SAE J1939protocol are researched，and a vehicle digital instrument solution based on MC9S12HZ256MCU is proposed.The message frame format and some engine-related parameters’definition in SAE J1939application layer protocol are introduced in detail.Stepper motor and its driver，the methods of speed signal process-ing are also introduced.The hardware platform of vehicle digital instrument is composed by MCU，signal acquisition mod-ule，and signal processing and displaying module.Data receiving and processing from CAN bus and sensors are accom-plished by programming，and vehicle condition can be reflected in real-time.
上傳時間： 2013-10-20
上傳用戶：huannan88
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