rising free r ising fr
上傳時間: 2013-12-25
上傳用戶:zhangyigenius
/*SPI規范:Data is always clocked into the device on the rising edge of SCK a-*/ /* nd clocked out of the device on the falling edge of SCK.All instruction-*/ /* s,addresses and data are transferred with the most significant bit(MSB) */ /* first.
上傳時間: 2016-02-19
上傳用戶:遠遠ssad
使用時鐘PLL的源同步系統時序分析一)回顧源同步時序計算Setup Margin = Min Clock Etch Delay – Max Data Etch Delay – Max Delay Skew – Setup TimeHold Margin = Min Data Etch Delay – Max Clock Etch Delay + Min Delay Skew + Data Rate – Hold Time下面解釋以上公式中各參數的意義:Etch Delay:與常說的飛行時間(Flight Time)意義相同,其值并不是從仿真直接得到,而是通過仿真結果的后處理得來。請看下面圖示:圖一為實際電路,激勵源從輸出端,經過互連到達接收端,傳輸延時如圖示Rmin,Rmax,Fmin,Fmax。圖二為對應輸出端的測試負載電路,測試負載延時如圖示rising,Falling。通過這兩組值就可以計算得到Etch Delay 的最大和最小值。
上傳時間: 2013-11-05
上傳用戶:VRMMO
Low power standby requirements are typically associatedwith battery-powered systems. Automotive systems,for example, commonly require power supplies tomaintain output voltage regulation even under no-loadconditions—while drawing minimal quiescent current topreserve battery life. rising energy costs, however, haveextended the need for low current standby operation toline-powered systems, such as small plugged-in appliancesfor home and business.
上傳時間: 2013-11-20
上傳用戶:xinyuzhiqiwuwu
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
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.
上傳時間: 2014-04-02
上傳用戶:han_zh
Embest Arm EduKit II Evaluation Board External Interrupt Test Example Please Select the trigger: 1 - Falling trigger 2 - rising trigger 3 - Both Edge trigger 4 - Low level trigger 5 - High level trigger any key to exit... Press the buttons push buttons may have glitch noise problem EINT6 had been occured... LED1 (D1204) on
標簽: Evaluation Interrupt External Example
上傳時間: 2015-10-08
上傳用戶:Altman
電路仿真程序 Classic Ladder is coded 100% in C.It can be used for educational purposes or anything you want... The graphical user interface uses GTK. In the actual version, the following elements are implemented : * Booleans elements * rising / falling edges * Timers * Monostables * Compare of arithmetic expressions
標簽: educational anything purposes Classic
上傳時間: 2014-01-13
上傳用戶:xg262122
vhdl編寫,8b—10b 編解碼器設計 Encoder: 8b/10b Encoder (file: 8b10b_enc.vhd) Synchronous clocked inputs (latched on each clock rising edge) 8-bit parallel unencoded data input KI input selects data or control encoding Asynchronous active high reset initializes all logic Encoded data output 10-bit parallel encoded output valid 1 clock later Decoder: 8b/10b Decoder (file: 8b10b_dec.vhd) Synchronous clocked inputs (latched on each clock rising edge) 10-bit parallel encoded data input Asynchronous active high reset initializes all logic Decoded data, disparity and KO outputs 8-bit parallel unencoded output valid 1 clock later
上傳時間: 2016-05-05
上傳用戶:gundamwzc
Finally: a hands-on, Java-centric workbook companion for the classic Design Patterns! Workbook approach deepens your understanding, builds your confidence, and strengthens your skills. Covers all five categories of design pattern intent: interfaces, responsibility, construction, operations, and extensions. CD-ROM contains all code examples from the book -- plus bonus code examples not found in the book. About the Author: Steven John Metsker is a researcher and author focused on advanced techniques for magnifying the abilities of object-oriented software developers. A rising star in the patterns community, he was recently invited to join the acclaimed Hillside Group. He is author of Building Parsers with Java? (Addison-Wesley).
標簽: Java-centric companion hands-on Patterns
上傳時間: 2013-12-01
上傳用戶:1079836864