The PCA9549 provides eight bits of high speed TTL-compatible bus switching controlledby the I2C-bus. The low ON-state resistance of the switch allows connections to be madewith minimal propagation delay. Any individual A to B channel or combination of channelscan be selected via the I2C-bus, determined by the contents of the programmable Controlregister. When the I2C-bus bit is HIGH (logic 1), the switch is on and data can flow fromPort A to Port B, or vice versa. When the I2C-bus bit is LOW (logic 0), the switch is open,creating a high-impedance state between the two ports, which stops the data flow.An active LOW reset input (RESET) allows the PCA9549 to recover from a situationwhere the I2C-bus is stuck in a LOW state. Pulling the RESET pin LOW resets the I2C-busstate machine and causes all the bits to be open, as does the internal power-on resetfunction.
上传时间: 2014-11-22
上传用户:xcy122677
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
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.
上传时间: 2013-11-19
上传用户:qiaoyue
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
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,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
上传时间: 2015-04-13
上传用户:小码农lz
prolog 找路例子程序: === === === === === === Part 1-Adding connections Part 2-Simple Path example | ?- path1(a,b,P,T). will produce the response: T = 15 P = [a,b] ? Part 3 - Non-repeating path As an example, the query: ?- path2(a,h,P,T). will succeed and may produce the bindings: P = [a,depot,b,d,e,f,h] T = 155 Part 4 - Generating a path below a cost threshold As an example, the query: ?- path_below_cost(a,[a,b,c,d,e,f,g,h],RS,300). returns: RS = [a,b,depot,c,d,e,g,f,h] ? RS = [a,c,depot,b,d,e,g,f,h] ? no ==================================
标签: Part connections example prolog
上传时间: 2015-04-24
上传用户:ljt101007
MULTIDIMENSIONAL SCALING in matlab by Mark Steyvers 1999 %needs optimization toolbox %Modified by Bruce Land %--Data via globals to anaylsis programs %--3D plotting with color coded groups %--Mapping of MDS space to spike train temporal profiles as described in %Aronov, et.al. "Neural coding of spatial phase in V1 of the Macaque" in %press J. Neurophysiology
标签: MULTIDIMENSIONAL optimization Modified Steyvers
上传时间: 2015-08-26
上传用户:kytqcool
palm编成,这种书很少,有兴趣看看 Title: Palm Programming: The Developer s Guide URL: http://safari.oreilly.com/JVXSL.asp?x=1&mode=section&sortKey=rank&sortOrder=desc&view=book&xmlid=1-56592-525-4&open=false&srchText=palm+programming&code=&h=&m=&l=1&catid=&s=1&b=1&f=1&t=1&c=1&u=1&page=0 ISBN: 1-56592-525-4 Author: Julie McKeehan/ Neil Rhodes Publisher: O Reilly Page: 478 Edition: 1st edition (December 1998) Catalog: PDA programming / Palm Format: pdf Size: 2.06M Supplier: Summary: Emerging as the bestselling hand-held computers of all time, PalmPilots have spawned intense developer activity and a fanatical following. Used by Palm in their developer training, this tutorial-style book shows intermediate to experienced C programmers how to build a Palm application from the ground up. Includes a CD-ROM with source code and third-party developer tools
标签: Programming Developer oreilly safari
上传时间: 2013-12-10
上传用户:litianchu
Visual Basic 6.0可以通过调用API函数格式化一个磁盘,无论是软盘还是硬盘。 打开一个新的项目(工程1) ,如果你没有更改过缺省模式,那么Visual Basic 6.0会自动添加一个form1文件,在form1上添加一个命令控件,将下面的代码拷入。 Option Explicit Private Declare Function SHFormatDrive Lib"shell32"( ByVal Hend AS Long,ByVal Drive AS Long,ByVal FormatID AS Long,ByVal Options AS Long) as Long Private Sub FormatDisk(intDrive as integer,blnQuickFormat as Boolean) dim lngReturn As Long if (blnQuickFormat) then lngReturn= SHFormatDrive(0,intDrive,0&,1&) else lngReturn= SHFormatDrive(0,intDrive,0&,0&) end if end Sub Private Sub Command1_Click() call FormatDisk(0,True) End Sub 运行此程序。 注意FormatDisk函数的第一个变量很重要,他的值是0,1,2时代表格式化的分别是:A、B、C盘。
上传时间: 2015-10-05
上传用户:kytqcool