What would happen if someone connected 24V to your12V circuits? If the power and ground lines were inadvertentlyreversed, would the circuits survive? Does yourapplication reside in a harsh environment, where the inputsupply can ring very high or even below ground? Evenif these Events are unlikely, it only takes one to destroya circuit board.
上传时间: 2013-10-26
上传用户:jackandlee
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
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.
上传时间: 2014-04-02
上传用户:han_zh
This article is a very simple introduction writing a Windows Form application for the Microsoft.NET framework using C#. The sample application demonstrates how to create and layout controls on a simple form and the handling of mouse click Events. The application displays a form showing attributes of a file. This form is similar to the properties dialog box of a file (Right click on a file and Click on Properties menu item). Since attributes of a file will be shown, the sample will show how to use File IO operations in .NET framework.
标签: introduction application Microsoft article
上传时间: 2015-04-09
上传用户:www240697738
JBoss, one of the leading java Open Source groups, integrates and develops these services for a full J2EE-based implementation. JBoss provides JBossServer, the basic EJB container, and Java Manage Preface 18 Great Events of the Twentieth Centuryment Extension (JMX) infrastructure. It also provides JBossMQ, for JMS messaging, JBossTX, for JTA/JTS transactions, JBossCMP for CMP persistence, JBossSX for JAAS based security, and JBossCX for JCA connectivity. Support for web components, such as servlets and JSP pages, is providedby an abstract integration layer. Implementations of the integration service are provided for third party servlet engines like Tomcat and Jetty. JBoss enables you to mix and match these components through JMX by replacing any component you want with a JMX compliant implementation for the same APIs.
标签: integrates develops services leading
上传时间: 2014-11-03
上传用户:wsf950131
一般会使用WINDOW API的情况,实在是因为VB本身不提供某些功能,但是,程式所 需又不得不然,例如:读取Registry内的资料,VB只提供SaveSetting、Getsetting 等 系列的指令,但是它只能读取特定地区的值,要读、删、更动其他区域的值时,就无法 使用。再如:仔细看一看Combo Box的Events,其中没有MouseMove,但这是我们经常用 上的一个Event,那该如何呢?是的,那只有透过Winodow API。而VB呼叫Window API一 般不都使用API检视员,直接将相对应的API COPY到我们的程式中就好,那还用什麽技 巧吗?其实不然,因为VB资料格式的问题,又加上VB本身没有指标,在许多地方需要一 些小技巧才能解决,而且我们经常因应不同的需求,将API 检视员的宣告COPY过来後再 做一些修改,最重要的,如果有一个.DLL档,它不在API 检视员中定义,那时,就只有 自己想办法啦。
上传时间: 2014-01-18
上传用户:sclyutian
Writing an Input Module The sample module introduced here is called idiom (Input Device for Intercepting Output of Mice), The sample module registers itself with the USB kernel subsystem as a mouse driver and with the input management subsystem as a keyboard driver. idiom translates mouse movement Events into keyboard input Events: it reports arrow Events to the input system according to how the physical mouse is moved.
标签: Input introduced Writing Device
上传时间: 2015-06-25
上传用户:731140412
Microsoft Press books are available through booksellers and distributors worldwide. For further information about international editions, contact your local Microsoft Corporation office or contact Microsoft Press International directly at fax (425) 936-7329. Visit our Web site at www.microsoft.com/mspress. Send comments to mspinput@microsoft.com. Microsoft, Microsoft Press, Visual Basic, Visual Studio, Windows, and Windows NT are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. Other product and company names mentioned herein may be the trademarks of their respective owners. The example companies, organizations, products, domain names, e-mail addresses, logos, people, places, and Events depicted herein are fictitious. No association with any real company, organization, product, domain name, e-mail address, logo, person, place, or event is intended or should be inferred.
标签: distributors booksellers Microsoft available
上传时间: 2013-12-27
上传用户:wuyuying
8点基二fft Fast Fourier Transform (FFT). Using 8 points, takes about 1.2 ms to execute one FFT. Sets up General Purpose Timer 1 to generate Events at 10 kHz. Will produce 10 kHz output on T1PWM and T1PWM pins.
标签: FFT Transform Fourier execute
上传时间: 2013-12-18
上传用户:Yukiseop
MODE_Switch1Processing multi-interrupt request needs to set the priority of these interrupt requests. The IRQ flags of the 7 interrupt are controlled by the interrupt event occurring. But the IRQ flag set doesn t mean the system to execute the interrupt vector. The IRQ flags can be triggered by the Events without interrupt enable. Just only any the event occurs and the IRQ will be logic "1".
标签: multi-interrupt MODE_Switch Processing interrupt
上传时间: 2013-12-04
上传用户:zhichenglu