The STWD100 watchdog timer circuits are self-contained devices which prevent systemfailures that are caused by certain types of hardware errors (non-responding peripherals,bus contention, etc.) or software errors (bad code jump, code stuck in loop, etc.).The STWD100 watchdog timer has an input, WDI, and an output, WDO (see Figure 2). Theinput is used to clear the internal watchdog timer periodically within the specified timeoutperiod, twd (see Section 3: Watchdog timing). While the system is operating correctly, itperiodically toggles the watchdog input, WDI. If the system fails, the watchdog timer is notreset, a system alert is generated and the watchdog output, WDO, is asserted (seeSection 3: Watchdog timing).The STWD100 circuit also has an enable pin, EN (see Figure 2), which can enable ordisable the watchdog functionality. The EN pin is connected to the internal pull-downresistor. The device is enabled if the EN pin is left floating.
上傳時間: 2013-10-22
上傳用戶:taiyang250072
本軟件是關于MAX338, MAX339的英文數據手冊:MAX338, MAX339 8通道/雙4通道、低泄漏、CMOS模擬多路復用器 The MAX338/MAX339 are monolithic, CMOS analog multiplexers (muxes). The 8-channel MAX338 is designed to connect one of eight inputs to a common output by control of a 3-bit binary address. The dual, 4-channel MAX339 is designed to connect one of four inputs to a common output by control of a 2-bit binary address. Both devices can be used as either a mux or a demux. On-resistance is 400Ω max, and the devices conduct current equally well in both directions. These muxes feature extremely low off leakages (less than 20pA at +25°C), and extremely low on-channel leakages (less than 50pA at +25°C). The new design offers guaranteed low charge injection (1.5pC typ) and electrostatic discharge (ESD) protection greater than 2000V, per method 3015.7. These improved muxes are pin-compatible upgrades for the industry-standard DG508A and DG509A. For similar Maxim devices with lower leakage and charge injection but higher on-resistance, see the MAX328 and MAX329.
上傳時間: 2013-11-12
上傳用戶:18711024007
PCB 被動組件的隱藏特性解析 傳統上,EMC一直被視為「黑色魔術(black magic)」。其實,EMC是可以藉由數學公式來理解的。不過,縱使有數學分析方法可以利用,但那些數學方程式對實際的EMC電路設計而言,仍然太過復雜了。幸運的是,在大多數的實務工作中,工程師并不需要完全理解那些復雜的數學公式和存在于EMC規范中的學理依據,只要藉由簡單的數學模型,就能夠明白要如何達到EMC的要求。本文藉由簡單的數學公式和電磁理論,來說明在印刷電路板(PCB)上被動組件(passivecomponent)的隱藏行為和特性,這些都是工程師想讓所設計的電子產品通過EMC標準時,事先所必須具備的基本知識。導線和PCB走線導線(wire)、走線(trace)、固定架……等看似不起眼的組件,卻經常成為射頻能量的最佳發射器(亦即,EMI的來源)。每一種組件都具有電感,這包含硅芯片的焊線(bond wire)、以及電阻、電容、電感的接腳。每根導線或走線都包含有隱藏的寄生電容和電感。這些寄生性組件會影響導線的阻抗大小,而且對頻率很敏感。依據LC 的值(決定自共振頻率)和PCB走線的長度,在某組件和PCB走線之間,可以產生自共振(self-resonance),因此,形成一根有效率的輻射天線。在低頻時,導線大致上只具有電阻的特性。但在高頻時,導線就具有電感的特性。因為變成高頻后,會造成阻抗大小的變化,進而改變導線或PCB 走線與接地之間的EMC 設計,這時必需使用接地面(ground plane)和接地網格(ground grid)。導線和PCB 走線的最主要差別只在于,導線是圓形的,走線是長方形的。導線或走線的阻抗包含電阻R和感抗XL = 2πfL,在高頻時,此阻抗定義為Z = R + j XL j2πfL,沒有容抗Xc = 1/2πfC存在。頻率高于100 kHz以上時,感抗大于電阻,此時導線或走線不再是低電阻的連接線,而是電感。一般而言,在音頻以上工作的導線或走線應該視為電感,不能再看成電阻,而且可以是射頻天線。
上傳時間: 2013-11-16
上傳用戶:極客
There are many manufacturers of dot matrix LCD modules. However, most of these displaysare similar. They all have on-board controllers and drivers capable of displaying alpha numericsand a wide variety of other symbols (including Japanese "Katakana" characters). The internaloperation of LCD controller devices is determined by signals sent from a central processing unit(in this case, a CoolRunner-II CPLD).
標簽: CoolRunner-II XAPP 904 LCD
上傳時間: 2013-12-17
上傳用戶:haiya2000
國外游戲開發者雜志2003年第二期配套代碼,包含了Jon Blow的交互工具的版本更新,使用了一個Kohonen Self-Organizing Feature Map來區分系統的行為
上傳時間: 2014-01-19
上傳用戶:拔絲土豆
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.
標簽: MIME described 64 encoding
上傳時間: 2013-12-17
上傳用戶:maizezhen
The flpydisk sample is a floppy driver that resides in the directory \\Ntddk\Src\Storage\Fdc\Flpydsk. It is similar to a class driver in that it sits a level above the floppy disk controller in the driver stack, and brokers communication between the application level and the low-level driver. The floppy driver takes commands from the application and then calls routines in the controller which will in turn perform the actual interaction with the device. The sample compiles in 64-bit, but has not been tested in this environment. It is compatible with x86 and Alpha platforms.
標簽: NtddkSrcStorageFdcFlpydsk directory flpydisk resides
上傳時間: 2015-03-30
上傳用戶:龍飛艇
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.
標簽: introduction application Microsoft article
上傳時間: 2015-04-09
上傳用戶:www240697738
We demonstrate a method for encoding and decoding the [24,12,8] extended binary Golay code using a simple apparatus. We also present several generalizations of this construction which admit similar decoding algorithms.
標簽: demonstrate decoding encoding extended
上傳時間: 2013-12-20
上傳用戶:moshushi0009
Abbrevia is a compression toolkit for Borland Delphi, C++Builder, & Kylix. It supports PKZIP 4, Microsoft CAB, TAR, & gzip formats & the creation of self-extracting archives. It includes visual components that simplify the manipulation of ZIP files.
標簽: compression Abbrevia supports Borland
上傳時間: 2014-01-13
上傳用戶:來茴