he LPC932 can be used to create a Pulse Width Modulated PWM signal. That s an analog signal, with only 2 discrete levels, for example 0V and 5V and a constant period. The current value of this signal at a certain poiTnt of time is proportional to its Duty Cycle. That s the High Time during one period divided by the period. It can also be calculated as the average value during a particular period. That means after low pass filtering, (e.g. RC circuit) the signal becomes analog, with an actual value controlled by the microcontroller. The PWM functionality enables the LPC932 to control for example the speed of DC motors or the brightness of electric lighting.
标签： signal Modulated analog create
上传时间： 2015-05-14
上传用户：CHINA526
10分钟学会SQl第三版 Sams Teach Yourself SQL in 10 Minutes has established itself as the gold standard for introductory SQL books, offering a fast-paced accessible tutorial to the major themes and techniques involved in applying the SQL language. Forta s examples are clear and his writing style is crisp and concise. As with earlier editions, this revision includes coverage of current versions of all major commercial SQL platforms. New this time around is coverage of MySQL, and PostgreSQL. All examples have been tested against each SQL platform, with incompatibilities or platform distinctives called out and explained.
标签： established Yourself standard Minutes
上传时间： 2014-07-07
上传用户：Pzj
解决时钟问题，acm竞赛题 A weird clock marked from 0 to 59 has only a minute hand. It won t move until a special coin is thrown into its box. There are different kinds of coins as your options. However once you make your choice, you cannot use any other kind. There are infinite number of coins of each kind, each marked with a number d ( 0 <= 1000 ), meaning that this coin will make the minute hand move d times clockwise the current time. For example, if the current time is 45, and d = 2. Then the minute hand will move clockwise 90 minutes and will be pointing to 15. Now you are given the initial time s ( 0 <= s <= 59 ) and the coin s type d. Write a program to find the minimum number of d-coins needed to turn the minute hand back to 0.
标签： 时钟
上传时间： 2015-05-21
上传用户：rishian
linux操作系统下运行，print current directory s files
上传时间： 2014-01-13
上传用户：shawvi
The government of a small but important country has decided that the alphabet needs to be streamlined and reordered. Uppercase letters will be eliminated. They will issue a royal decree in the form of a String of B and A characters. The first character in the decree specifies whether a must come ( B )Before b in the new alphabet or ( A )After b . The second character determines the relative placement of b and c , etc. So, for example, "BAA" means that a must come Before b , b must come After c , and c must come After d . Any letters beyond these requirements are to be excluded, so if the decree specifies k comparisons then the new alphabet will contain the first k+1 lowercase letters of the current alphabet. Create a class Alphabet that contains the method choices that takes the decree as input and returns the number of possible new alphabets that conform to the decree. If more than 1,000,000,000 are possible, return -1. Definition
标签： government streamline important alphabet
上传时间： 2015-06-09
上传用户：weixiao99
Rotating shafts experience a an elliptical motion called whirl. It is important to decompose this motion into a forward and backward whil orbits. The current function makes use of two sensors to generate a bi-directional spectrogram. The method can be extended to any time-frequency distribution ％ ％ compute the forward/backward Campbell/specgtrogram ％ ％ INPUT: ％ y (n x 2) each column is measured from a different sensor ％ /////// ％ __ ％ |s1| y(:,1) ％ |__| ％ __ ％ / \ ________|/ ％ | | | s2 |/ y(:,2) ％ \____/ --------|/ ％ ％ Fs Sampling frequnecy ％ ％ OUTPUT: ％ B spectrogram/Campbel diagram ％ x x-axis coordinate vector (time or Speed) ％ y y-axis coordinate vector (frequency [Hz])
标签： experience elliptical decompose important
上传时间： 2015-06-23
上传用户：372825274
This demo develops the steady-state characteristics of an induction motor First start the simulation, then Double click the <PLOTS> block to view torque-speed and current-speed curves and the current circle diagram
标签： characteristics steady-state simulation the
上传时间： 2013-11-29
上传用户：daguda
c8051f020 实时时钟模块程序 内含IIC模块程序/********************** SYSTEM CLOCK 8M********************************/ extern unsigned char xdata currenttime[16]={0} extern unsigned char xdata settime[16]={ 0x00, // control regesiter 1 0x00, // control regesiter 2 0x01, //current second 0x19, //current minute 0x20, //current hour 0x29, //current data 0x04, //current week 0x07, //current month 0x05, //current year 0x00, // alarm value reset 0x00, // alarm value reset 0x00, // alarm value reset 0x00, // alarm value reset 0x00, // clk out disable 0x00, // close timer 0x00, } /*********************************************************************/ extern void current_Time ( void ) extern void Set_Time ( void )
标签： c8051f020 SYSTEM CLOCK IIC
上传时间： 2015-06-30
上传用户：edisonfather
Wavelets have widely been used in many signal and image processing applications. In this paper, a new serial-parallel architecture for wavelet-based image compression is introduced. It is based on a 4-tap wavelet transform, which is realised using some FIFO memory modules implementing a pixel-level pipeline architecture to compress and decompress images. The real filter calculation over 4 · 4 window blocks is done using a tree of carry save adders to ensure the high speed processing required for many applications. The details of implementing both compressor and decompressor sub-systems are given. The primarily analysis reveals that the proposed architecture, implemented using current VLSI technologies, can process a video stream in real time.
标签： applications processing Wavelets widely
上传时间： 2014-01-22
上传用户：hongmo
RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating system designed for embedded systems. The acronym RTEMS initially stood for Real-Time Executive for Missile Systems, then became Real-Time Executive for Military Systems before changing to its current meaning. RTEMS development began in the late 1980s with early versions of RTEMS available via ftp as early as 1993. OAR Corporation is currently managing the RTEMS project in cooperation with a Steering Committee which includes user representatives.
标签： Multiprocessor Executive Real-Time real-time
上传时间： 2015-08-09
上传用户：D&L37
