隨著電子技術和EDA技術的發展,大規模可編程邏輯器件PLD(Programmable Logic Device)、現場可編程門陣列FPGA(Field Programmable Gates Array)完全可以取代大規模集成電路芯片,實現計算機可編程接口芯片的功能,并可將若干接口電路的功能集成到一片PLD或FPGA中.基于大規模PLD或FPGA的計算機接口電路不僅具有集成度高、體積小和功耗低等優點,而且還具有獨特的用戶可編程能力,從而實現計算機系統的功能重構.該課題以Altera公司FPGA(FLEX10K)系列產品為載體,在MAX+PLUSⅡ開發環境下采用VHDL語言,設計并實現了計算機可編程并行接芯片8255的功能.設計采用VHDL的結構描述風格,依據芯片功能將系統劃分為內核和外圍邏輯兩大模塊,其中內核模塊又分為RORT A、RORT B、OROT C和Control模塊,每個底層模塊采用RTL(Registers Transfer Language)級描述,整體生成采用MAX+PLUSⅡ的圖形輸入法.通過波形仿真、下載芯片的測試,完成了計算機可編程并行接芯片8255的功能.
上傳時間： 2013-06-08
上傳用戶：asddsd
介紹了用單片機C 語言實現無功補償中電容組循環投切的基本原理和算法，并舉例說明。關鍵詞：循環投切;C51;無功補償中圖分類號： TM76 文獻標識碼： BAbstract: This paper introduces the aplication of C51 in the controlling of capacitorsuits cycle powered to be on and off in reactive compensation.it illustrate thefondamental principle and algorithm with example.Key words: cycle powered to be on and off; C51; reactive compensation 為提高功率因數，往往采用補償電容的方法來實現。而電容器的容量是由實時功率因數與標準值進行比較來決定的，實時功率因數小于標準值時，需投入電容組，實時功率因數大于標準值時，則需切除電容組。投切方式的不合理，會對電容器造成損壞，現有的控制器多采用“順序投切”方式，在這種投切方式下排序在前的電容器組，先投后切；而后面的卻后投先切。這不僅使處于前面的電容組經常處于運行狀態，積累熱量不易散失，影響其使用壽命，而且使后面的投切開關經常動作，同樣減少壽命。合理的投切方式應為“循環投切”。這種投切方式使先投入的運行的電容組先退出，后投的后切除，從而使各組電容及投切開關使用機率均等，降低了電容組的平均運行溫度，減少了投切開關的動作次數，延長了其使用壽命。
上傳時間： 2014-12-27
上傳用戶：hopy
All inputs of the C16x family have Schmitt-Trigger input characteristics. These Schmitt-Triggers are intended to always provide proper internal low and high levels, even if anundefined voltage level (between TTL-VIL and TTL-VIH) is externally applied to the pin.The hysteresis of these inputs, however, is very small, and can not be properly used in anapplication to suppress signal noise, and to shape slow rising/falling input transitions.Thus, it must be taken care that rising/falling input signals pass the undefined area of theTTL-specification between VIL and VIH with a sufficient rise/fall time, as generally usualand specified for TTL components (e.g. 74LS series: gates 1V/us, clock inputs 20V/us).The effect of the implemented Schmitt-Trigger is that even if the input signal remains inthe undefined area, well defined low/high levels are generated internally. Note that allinput signals are evaluated at specific sample points (depending on the input and theperipheral function connected to it), at that signal transitions are detected if twoconsecutive samples show different levels. Thus, only the current level of an input signalat these sample points is relevant, that means, the necessary rise/fall times of the inputsignal is only dependant on the sample rate, that is the distance in time between twoconsecutive evaluation time points. If an input signal, for instance, is sampled throughsoftware every 10us, it is irrelevant, which input level would be seen between thesamples. Thus, it would be allowable for the signal to take 10us to pass through theundefined area. Due to the sample rate of 10us, it is assured that only one sample canoccur while the signal is within the undefined area, and no incorrect transition will bedetected. For inputs which are connected to a peripheral function, e.g. capture inputs, thesample rate is determined by the clock cycle of the peripheral unit. In the case of theCAPCOM unit this means a sample rate of 400ns @ 20MHz CPU clock. This requiresinput signals to pass through the undefined area within these 400ns in order to avoidmultiple capture events.For input signals, which do not provide the required rise/fall times, external circuitry mustbe used to shape the signal transitions.In the attached diagram, the effect of the sample rate is shown. The numbers 1 to 5 in thediagram represent possible sample points. Waveform a) shows the result if the inputsignal transition time through the undefined TTL-level area is less than the time distancebetween the sample points (sampling at 1, 2, 3, and 4). Waveform b) can be the result ifthe sampling is performed more than once within the undefined area (sampling at 1, 2, 5,3, and 4).Sample points:1. Evaluation of the signal clearly results in a low level2. Either a low or a high level can be sampled here. If low is sampled, no transition willbe detected. If the sample results in a high level, a transition is detected, and anappropriate action (e.g. capture) might take place.3. Evaluation here clearly results in a high level. If the previous sample 2) had alreadydetected a high, there is no change. If the previous sample 2) showed a low, atransition from low to high is detected now.
上傳時間： 2013-10-23
上傳用戶：copu
mp3設計程序資料，采用c語言編寫。 README file for yampp-3 source code 2001-05-27 This is the current state of the yampp-3 source code, 2001-05-27. This code is intended to run on Rev. B of the yampp-3 PCB, but can ofcourse be used on compatible systems as well. It still uses the "old" song selection system as the yampp-2. However, the disk handling routines has improved a lot and the obviosly, the new VS1001 handling has been put in. The codesize is almost at it s maximum at 1F40 bytes. A .ROM file is included if you don t have the compiler set up. For now, the documentation is in the code
上傳時間： 2015-04-13
上傳用戶：小碼農lz
Implemented BFS, DFS and A* To compile this project, use the following command: g++ -o search main.cpp Then you can run it: ./search The input is loaded from a input file in.txt Here is the format of the input file: The first line of the input file shoud contain two chars indicate the source and destination city for breadth first and depth first algorithm. The second line of input file shoud be an integer m indicate the number of connections for the map. Following m lines describe the map, each line represents to one connection in this form: dist city1 city2, which means there is a connection between city1 and city2 with the distance dist. The following input are for A* The following line contains two chars indicate the source and destination city for A* algorithm. Then there is an integer h indicate the number of heuristic. The following h lines is in the form: city dist which means the straight-line distance from the city to B is dist.
標簽： Implemented following compile command
上傳時間： 2014-01-01
上傳用戶：lhc9102
acm HDOJ 1051WoodenSticks Description: There is a pile of n wooden sticks. The length and weight of each stick are known in advance. The sticks are to be processed by a woodworking machine in one by one fashion. It needs some time, called setup time, for the machine to prepare processing a stick. The setup times are associated with cleaning operations and changing tools and shapes in the machine. The setup times of the woodworking machine are given as follows: (a) The setup time for the first wooden stick is 1 minute. (b) Right after processing a stick of length l and weight w , the machine will need no setup time for a stick of length l and weight w if l<=l and w<=w . Otherwise, it will need 1 minute for setup.
標簽： WoodenSticks Description length wooden
上傳時間： 2014-03-08
上傳用戶：netwolf
This a vhdl programme for realise an electron watch by max-plus II. The function includes time showing and time setting. It may be extended to other functions like alarming clock and so forth.
標簽： programme electron max-plus function
上傳時間： 2013-12-26
上傳用戶：dbs012280
the calculator s usage! after you have inputed 2 operators,choose + - * / function! But the only situation I did t deal with is that when you choos + fuction ,and the operaters signs is like this -A+B,just turn it to B-A!
標簽： calculator the operators function
上傳時間： 2016-02-12
上傳用戶：lili123
DirectX not only provides fast access to the hardware and therefore incredibly speedy performance, but it also makes it much easier for hardware developers to produce new devices that work well in the Windows environment. The DirectX APIs take away the necessity of writing your own low-level, device-specific code to access hardware such as the display adapter and network card, making it much easier for you to write programs that take full advantage of the computer s multimedia capabilities.
標簽： performance incredibly therefore hardware
上傳時間： 2016-02-16
上傳用戶：秦莞爾w
Generate 100 samples of a zero-mean white noise sequence with variance , by using a uniform random number generator. a Compute the autocorrelation of for . b Compute the periodogram estimate and plot it. c Generate 10 different realizations of , and compute the corresponding sample autocorrelation sequences , and . Compute the average autocorrelation sequence as and the corresponding periodogram for . d Compute and plot the average periodogram using the Bartlett method. e Comment on the results in parts (a) through (d).
標簽： zero-mean Generate sequence variance
上傳時間： 2016-03-04
上傳用戶：朗朗乾坤
