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.
上传时间: 2013-10-23
上传用户:copu
WHAT MIME64 IS: MIME64 is an encoding described in RFC1341 as MIME base64.Its purpose is to encode binary files into ASCII so that they may be passedthrough e-mail gates. In this regard, MIME64 is similar to UUENCODE.Although most binaries these days are transmitted using UUENCODE, Ihave seen a few using MIME64, and I have had requests from friends thatI decode MIME64 files that have fallen into their hands. As long assome MIME64 continues to exist, a package such as this one is usefulto have.
标签: MIME described 64 encoding
上传时间: 2013-12-17
上传用户:maizezhen
A simple C program to strobe the LEDsvia Port D. The strobe rate is to be set by adjusting the voltage drop over a potentiometer that is sampled by an ADC.
上传时间: 2014-01-09
上传用户:lifangyuan12
mp3设计程序资料,采用c语言编写。 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
上传时间: 2015-04-13
上传用户:小码农lz
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
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.
标签: Implemented following compile command
上传时间: 2014-01-01
上传用户: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.
标签: WoodenSticks Description length wooden
上传时间: 2014-03-08
上传用户:netwolf
Swfdec still is development software, but has also followed a rigid no-crashes-allowed policy. I believe it s stable enough now to be installed as a default plugin for people that can live with occasional crashes of their browser. But don t blame me if it does crash. File a bug at https://bugs.freedesktop.org/enter_bug.cgi?product=swfdec
标签: no-crashes-allowed development followed software
上传时间: 2016-04-14
上传用户:franktu
segment,一个简单的中文分词程序,命令行如下: java -jar segmenter.jar [-b|-g|-8|-s|-t] inputfile.txt -b Big5, -g GB2312, -8 UTF-8, -s simp. chars, -t trad. chars Segmented text will be saved to inputfile.txt.seg
上传时间: 2014-01-04
上传用户:ynzfm
Accurate estimates of the autocorrelation or power spectrum can be obtained with a parametric model (AR, MA or ARMA). With automatic inference, not only the model parameters but also the model structure are determined from the data. It is assumed that the ARMASA toolbox is presen
标签: autocorrelation parametric estimates Accurate
上传时间: 2013-12-29
上传用户:3到15