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  • Extension for LockBox for Delphi 7. This pack help for install the previous version of the LockBox f

    Extension for LockBox for Delphi 7. This pack help for install the previous version of the LockBox for Delphi 2007.

    标签: LockBox for Extension the

    上传时间: 2013-12-11

    上传用户:dapangxie

  • CSMA / CD simulation code, Gigabit Ethernet previous versions used to compete for a unified approach

    CSMA / CD simulation code, Gigabit Ethernet previous versions used to compete for a unified approach, in order to decide on the right of media access, which relates to the backoff algorithm. OPNET environment can be achieved through the experience card.

    标签: simulation Ethernet approach previous

    上传时间: 2014-01-05

    上传用户:yangbo69

  • 高效LCD液晶照明技术

    In August of 1992 LTC published Application Note 49, “Illumination Circuitry for Liquid Crystal Displays.” One notable aspect of this event is that it generated more response than all previous LTC application notes combined. This level of interest, along with significant performance advances since AN-49’s appearance, justifies further discussion of LCD backlighting circuitry.

    标签: LCD 液晶 照明技术

    上传时间: 2013-11-19

    上传用户:lanjisu111

  • USB Demonstration for DK3200 w

    The μPSD32xx family, from ST, consists of Flash programmable system devices with a 8032 MicrocontrollerCore. Of these, the μPSD3234A and μPSD3254A are notable for having a complete implementationof the USB hardware directly on the chip, complying with the Universal Serial Bus Specification, Revision1.1.This application note describes a demonstration program that has been written for the DK3200 hardwaredemonstration kit (incorporating a μPSD3234A device). It gives the user an idea of how simple it is to workwith the device, using the HID class as a ready-made device driver for the USB connection.IN-APPLICATION-PROGRAMMING (IAP) AND IN-SYSTEM-PROGRAMMING (ISP)Since the μPSD contains two independent Flash memory arrays, the Micro Controller Unit (MCU) can executecode from one memory while erasing and programming the other. Product firmware updates in thefield can be reliably performed over any communication channel (such as CAN, Ethernet, UART, J1850)using this unique architecture. For In-Application-Programming (IAP), all code is updated through theMCU. The main advantage for the user is that the firmware can be updated remotely. The target applicationruns and takes care on its own program code and data memory.IAP is not the only method to program the firmware in μPSD devices. They can also be programmed usingIn-System-Programming (ISP). A IEEE1149.1-compliant JTAG interface is included on the μPSD. Withthis, the entire device can be rapidly programmed while soldered to the circuit board (Main Flash memory,Secondary Boot Flash memory, the PLD, and all configuration areas). This requires no MCU participation.The MCU is completely bypassed. So, the μPSD can be programmed or reprogrammed any time, anywhere, even when completely uncommitted.Both methods take place with the device in its normal hardware environment, soldered to a printed circuitboard. The IAP method cannot be used without previous use of ISP, because IAP utilizes a small amountof resident code to receive the service commands, and to perform the desired operations.

    标签: Demonstration 3200 USB for

    上传时间: 2014-02-27

    上传用户:zhangzhenyu

  • 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

  • PL2303 USB to Serial Adapter

    The PL2303 USB to Serial adapter is your smart and convenient accessory forconnecting RS-232 serial devices to your USB-equipped Windows host computer. Itprovides a bridge connection with a standard DB 9-pin male serial port connector inone end and a standard Type-A USB plug connector on the other end. You simplyattach the serial device onto the serial port of the cable and plug the USB connectorinto your PC USB port. It allows a simple and easy way of adding serial connectionsto your PC without having to go thru inserting a serial card and traditional portconfiguration.This USB to Serial adapter is ideal for connecting modems, cellular phones, PDAs,digital cameras, card readers and other serial devices to your computer. It providesserial connections up to 1Mbps of data transfer rate. And since USB does not requireany IRQ resource, more devices can be attached to the system without the previoushassles of device and resource conflicts.Finally, the PL-2303 USB to Serial adapter is a fully USB Specification compliantdevice and therefore supports advanced power management such as suspend andresume operations as well as remote wakeup. The PL-2303 USB Serial cable adapteris designed to work on all Windows operating systems.

    标签: Adapter Serial 2303 USB

    上传时间: 2013-11-01

    上传用户:ghostparker

  • Locally weighted polynomial regression LWPR is a popular instance based al gorithm for learning c

    Locally weighted polynomial regression LWPR is a popular instance based al gorithm for learning continuous non linear mappings For more than two or three in puts and for more than a few thousand dat apoints the computational expense of pre dictions is daunting We discuss drawbacks with previous approaches to dealing with this problem

    标签: polynomial regression weighted instance

    上传时间: 2013-11-28

    上传用户:sunjet

  • Software Testing, Second Edition provides practical insight into the world of software testing and q

    Software Testing, Second Edition provides practical insight into the world of software testing and quality assurance. Learn how to find problems in any computer program, how to plan an effective test approach and how to tell when software is ready for release. Updated from the previous edition in 2000 to include a chapter that specifically deals with testing software for security bugs, the processes and techniques used throughout the book are timeless. This book is an excellent investment if you want to better understand what your Software Test team does or you want to write better software.

    标签: practical Software provides software

    上传时间: 2015-04-30

    上传用户:bjgaofei

  • Expert Choice represents a significant contribution to the decision making process 工t assists a deci

    Expert Choice represents a significant contribution to the decision making process 工t assists a decision maker in solving complex problems involving many criteria and several courses of action . An Expert Choice solution to a problem reflects the expertise of the decision maker , not the computer . Behavioral scientists have spent many years studying the human mind and how it makes decisions . They have found that humans are influenced by their previous experiences and this causes them to have biases . Basic instincts , preferences and environmental factors also play key roles in how we analyze data and make decisions . There 15 way to remove these factors from human decision making , nor would we necessarily want to , but as the problems of our world become more and more complex , it 15 necessary for us to employ a framework to help make more logical and less biased decisions while still taking our feelings and intuition into consideration .

    标签: contribution significant represents decision

    上传时间: 2015-06-02

    上传用户:gmh1314

  • This PNG Delphi version 1.56 documentation (this version is a major rewrite intended to replace the

    This PNG Delphi version 1.56 documentation (this version is a major rewrite intended to replace the previous version, 1.2). Improvements in this new version includes: This new version allows the programmer to not use Delphi heavy units which will greatly reduce the size of the final executable. Read more about this feature here. Most, if not all, Portable Network Graphics features as CRC checking are now fully performed. Error on broken images are now better handled using new exception classes. The images may be saved using interlaced mode also. Transparency information won t be discarted after the image is loaded any more. Most of the images are decoded much faster now. The images will be better encoded using fresh new algorithms. IMPORTANT! Now transparency information is used to display images.

    标签: version documentation intended rewrite

    上传时间: 2015-06-28

    上传用户:qiao8960