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  • Input Signal Rise and Fall Tim

    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.

    标签: Signal Input Fall Rise

    上传时间: 2013-10-23

    上传用户:copu

  • MPC7400l零件号码规范说明

    This document describes part number speciÞc changes to recommended operating conditions and revised electrical speciÞcations,as applicable, from those described in the generalMPC7400 Hardware SpeciÞcations.SpeciÞcations provided in this Part Number SpeciÞcation supersede those in theMPC7400 Hardware SpeciÞcationsdated 9/99(order #: MPC7400EC/D) for these part numbers only; speciÞcations not addressed herein are unchanged. This document isfrequently updated, refer to the website at http://www.mot.com/SPS/PowerPC/ for the latest version.Note that headings and table numbers in this data sheet are not consecutively numbered. They are intended to correspond to theheading or table affected in the general hardware speciÞcation.Part numbers addressed in this document are listed in Table A. For more detailed ordering information see Table B.

    标签: 7400l 7400 MPC 零件

    上传时间: 2013-11-19

    上传用户:qiaoyue

  • RT9018,RT9018AB-05 datasheet pdf

    The RT9018A/B is a high performance positive voltage regulator designed for use in applications requining very low Input voltage and very low dropout voltage at up to 3A(peak).

    标签: 9018 datasheet RT

    上传时间: 2013-10-10

    上传用户:geshaowei

  • dances Act now and you ll be given a free membership to a top Internet firm who is changing people s

    dances Act now and you ll be given a free membership to a top Internet firm who is changing people s lives for the better.Mary L. White of LA. stays at home with her children and works just 3 1/2 hours a day... she now earns twice as much money as she did before. Frank Herns Jr. of NY takes 2 vacations a year to the Caribbean and enjoys more time and freedom than ever before. Jane Kennedy of FL fired her boss after 5 months. She finally has the time and money she needs to complete her college education. Craig Garcia of CA tripled his income in just 90 days because took advantage of his free membership.

    标签: membership Internet changing dances

    上传时间: 2015-03-08

    上传用户:xhz1993

  • 最新的支持向量机工具箱

    最新的支持向量机工具箱,有了它会很方便 1. Find time to write a proper list of things to do! 2. Documentation. 3. Support Vector Regression. 4. Automated model selection. REFERENCES ========== [1] V.N. Vapnik, "The Nature of Statistical Learning Theory", Springer-Verlag, New York, ISBN 0-387-94559-8, 1995. [2] J. C. Platt, "Fast training of support vector machines using sequential minimal optimization", in Advances in Kernel Methods - Support Vector Learning, (Eds) B. Scholkopf, C. Burges, and A. J. Smola, MIT Press, Cambridge, Massachusetts, chapter 12, pp 185-208, 1999. [3] T. Joachims, "Estimating the Generalization Performance of a SVM Efficiently", LS-8 Report 25, Universitat Dortmund, Fachbereich Informatik, 1999.

    标签: 支持向量机 工具箱

    上传时间: 2013-12-16

    上传用户:亚亚娟娟123

  • The Kannel Open Source WAP and SMS gateway works as both an SMS gateway, for implementing keyword b

    The Kannel Open Source WAP and SMS gateway works as both an SMS gateway, for implementing keyword based services via GSM text messages, and a WAP gateway, via UDP. The SMS part is fairly mature, the WAP part is early in its development. In this release, the GET request for WML pages and WMLScript files via HTTP works, including compilation for WML and WMLScript to binary forms. Only the data call bearer (UDP) is supported, not SMS.

    标签: gateway implementing SMS keyword

    上传时间: 2014-01-11

    上传用户:2525775

  • USB Manager(usbmgr) 0.4.8 Shuu Yamaguchi <shuu@wondernetworkresources.com> Special Helper: Phi

    USB Manager(usbmgr) 0.4.8 Shuu Yamaguchi <shuu@wondernetworkresources.com> Special Helper: Philipp Thomas When USB devices connect to or disconnect from a USB hub, the usbmgr works as the following according to configuration. a) It loads and unloads files Linux kernel modules. b) It execute file to setup USB devices.

    标签: wondernetworkresources Yamaguchi Manager Special

    上传时间: 2014-01-27

    上传用户:zhaiyanzhong

  • 算法ebook(10部算法经典著作的合集) 算法ebook> 10部算法经典著作的合集 chm格式 (1)Fundamentals of Data Structures by Ellis Hor

    算法ebook(10部算法经典著作的合集) 算法ebook> 10部算法经典著作的合集 chm格式 (1)Fundamentals of Data Structures by Ellis Horowitz and Sartaj Sahni (2)Data Structures, Algorithms and Program Style Using C by James F. Korsh and Leonard J. Garrett (3)Data Structures and Algorithm Analysis in C by Mark Allen Weiss (4)Data Structures: From Arrays to Priority Queues by Wayne Amsbury (5)Information Retrieval: Data Structures & Algorithms edited by William B. Frakes and Ricardo Baeza-Yates (6)Introduction to Algorithms by Thomas H. Cormen, Charles E. Leiserson, and Ronald L. Rivest (7)Practical Data Structures in C++ by Bryan Flamig (8)Reliable Data Structures in C by Thomas Plum (9)Data Structures and Algorithms Alfred V. Aho, Bell Laboratories, Murray Hill, New Jersey John E. Hopcroft, Cornell University, Ithaca, New York Jeffrey D. Ullman, Stanford University, Stanford, California (10)DDJ Algorithms and Data Structures Articles

    标签: ebook Fundamentals Structures Ellis

    上传时间: 2015-04-04

    上传用户:tfyt

  • Description: FASBIR(Filtered Attribute Subspace based Bagging with Injected Randomness) is a variant

    Description: FASBIR(Filtered Attribute Subspace based Bagging with Injected Randomness) is a variant of Bagging algorithm, whose purpose is to improve accuracy of local learners, such as kNN, through multi-model perturbing ensemble. Reference: Z.-H. Zhou and Y. Yu. Ensembling local learners through multimodal perturbation. IEEE Transactions on Systems, Man, and Cybernetics - Part B: Cybernetics, 2005, vol.35, no.4, pp.725-735.

    标签: Description Randomness Attribute Filtered

    上传时间: 2015-04-10

    上传用户:ynzfm

  • mp3设计程序资料

    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

    标签: mp3 设计程序

    上传时间: 2015-04-13

    上传用户:小码农lz