1.1MCS51實驗系統安裝與啟動1.DVCC系列實驗系統在出廠時均為51狀態對DVCC—52196JH機型:SK1位1—5置ON位置,位6—10置OFF對DVCC—5286JH和DVCC—598JH機型:a.SK1位1—5置ON,位6—10置OFF;b.SK2位1—2置ON;c.SK3置ON;d.SK4置OFFe.臥式KBB置51、96位置,立式KBB1開關置51、88位置(只對DVCC—598JH/JH+);f.DL1—DL4連1、22.如果系統用于仿真外接用戶系統,將40芯仿真電纜一頭插入系統中J6插座,另一頭插入用戶系統的8051CPU位置,注意插入方向,仿真頭上小紅點表示第一腳,對應用戶8051CPU第一腳。3.接上+5V電源,將隨機配備的2芯電源線,紅線接入外置電源的+5V插孔,黑線接入外置電源地插座。上電后,DVCC系列實驗系統上顯示“P.”閃動。如果是獨立運行,按DVCC系列用戶手冊進入鍵盤管理監控,就能馬上做實驗。鍵盤管理監控操作詳見第一分冊第四章。如果連上位機工作,必須將隨機配備的D型9芯插頭一端插入DVCC系統J2插座,另一端插入上位機串行口COM1—COM2任選。然后按DVCC實驗系統PCDBG鍵,再運行上位機上的DVCC聯機軟件,雙方建立通信,往后詳細操作見用戶手冊第五章。如果電源內置,只需打開~220V電源開關即可。
上傳時間: 2013-10-12
上傳用戶:xc216
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.
上傳時間: 2014-11-22
上傳用戶: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.
上傳時間: 2013-10-23
上傳用戶:copu
基于USB接口的數據采集模塊的設計與實現Design and Implementation of USB-Based Data Acquisition Module路 永 伸(天津科技大學電子信息與自動化學院,天津300222)摘要文中給出基于USB接口的數據采集模塊的設計與實現。硬件設計采用以Adpc831與PDIUSBDI2為主的器件進行硬件設計,采用Windriver開發USB驅動,并用Visual C十十6.0對主機軟件中硬件接口操作部分進行動態鏈接庫封裝。關鍵詞USB 數據采集Adpc831 PDNSBDI2 Windriver動態鏈接庫Abstract T hed esigna ndim plementaitono fU SB-BasedD ataA cquisiitonM oduleis g iven.Th ec hips oluitonm ainlyw ithA dpc831a ndP DTUSBD12i sused for hardware design. The USB drive is developed場Wmdriver, and the operation on the hardware interface is packaged into Dynamic Link Libraries場Visual C++6.0. Keywords USB DataA cquisition Adttc831 PDfUSBD12 Windriver0 引言US B總 線 是新一代接口總線,最初推出的目的是為了統一取代PC機的各類外設接口,迄今經歷了1.0,1.1與2.0版本3個標準。在國內基于USB總線的相關設計與開發也得到了快速的發展,很多設計者從各自的應用領域,用不同方案設計出了相應的裝置[1,2]。數據采集是工業控制中一個普遍而重要的環節,因此開發基于USB接口的數據采集模塊具有很強的現實應用意義。雖然 US B總線標準已經發展到2.0版本,但由于工業控制現場干擾信號的情況比較復雜,高速數據傳輸的可靠性不容易被保證,并且很多場合對數據采集的實時性要求并不高,開發2.0標準產品的成本又較1.1標準產品高,所以筆者認為,在工業控制領域,目前開發基于USB總線1.1標準實現的數據采集模塊的實用意義大于相應2.0標準模塊。
上傳時間: 2013-10-23
上傳用戶:q3290766
磁芯電感器的諧波失真分析 摘 要:簡述了改進鐵氧體軟磁材料比損耗系數和磁滯常數ηB,從而降低總諧波失真THD的歷史過程,分析了諸多因數對諧波測量的影響,提出了磁心性能的調控方向。 關鍵詞:比損耗系數, 磁滯常數ηB ,直流偏置特性DC-Bias,總諧波失真THD Analysis on THD of the fer rite co res u se d i n i nductancShi Yan Nanjing Finemag Technology Co. Ltd., Nanjing 210033 Abstract: Histrory of decreasing THD by improving the ratio loss coefficient and hysteresis constant of soft magnetic ferrite is briefly narrated. The effect of many factors which affect the harmonic wave testing is analysed. The way of improving the performance of ferrite cores is put forward. Key words: ratio loss coefficient,hysteresis constant,DC-Bias,THD 近年來,變壓器生產廠家和軟磁鐵氧體生產廠家,在電感器和變壓器產品的總諧波失真指標控制上,進行了深入的探討和廣泛的合作,逐步弄清了一些似是而非的問題。從工藝技術上采取了不少有效措施,促進了質量問題的迅速解決。本文將就此熱門話題作一些粗淺探討。 一、 歷史回顧 總諧波失真(Total harmonic distortion) ,簡稱THD,并不是什么新的概念,早在幾十年前的載波通信技術中就已有嚴格要求<1>。1978年郵電部公布的標準YD/Z17-78“載波用鐵氧體罐形磁心”中,規定了高μQ材料制作的無中心柱配對罐形磁心詳細的測試電路和方法。如圖一電路所示,利用LC組成的150KHz低通濾波器在高電平輸入的情況下測量磁心產生的非線性失真。這種相對比較的實用方法,專用于無中心柱配對罐形磁心的諧波衰耗測試。 這種磁心主要用于載波電報、電話設備的遙測振蕩器和線路放大器系統,其非線性失真有很嚴格的要求。 圖中 ZD —— QF867 型阻容式載頻振蕩器,輸出阻抗 150Ω, Ld47 —— 47KHz 低通濾波器,阻抗 150Ω,阻帶衰耗大于61dB, Lg88 ——并聯高低通濾波器,阻抗 150Ω,三次諧波衰耗大于61dB Ld88 ——并聯高低通濾波器,阻抗 150Ω,三次諧波衰耗大于61dB FD —— 30~50KHz 放大器, 阻抗 150Ω, 增益不小于 43 dB,三次諧波衰耗b3(0)≥91 dB, DP —— Qp373 選頻電平表,輸入高阻抗, L ——被測無心罐形磁心及線圈, C ——聚苯乙烯薄膜電容器CMO-100V-707APF±0.5%,二只。 測量時,所配用線圈應用絲包銅電磁線SQJ9×0.12(JB661-75)在直徑為16.1mm的線架上繞制 120 匝, (線架為一格) , 其空心電感值為 318μH(誤差1%) 被測磁心配對安裝好后,先調節振蕩器頻率為 36.6~40KHz, 使輸出電平值為+17.4 dB, 即選頻表在 22′端子測得的主波電平 (P2)為+17.4 dB,然后在33′端子處測得輸出的三次諧波電平(P3), 則三次諧波衰耗值為:b3(+2)= P2+S+ P3 式中:S 為放大器增益dB 從以往的資料引證, 就可以發現諧波失真的測量是一項很精細的工作,其中測量系統的高、低通濾波器,信號源和放大器本身的三次諧波衰耗控制很嚴,阻抗必須匹配,薄膜電容器的非線性也有相應要求。濾波器的電感全由不帶任何磁介質的大空心線圈繞成,以保證本身的“潔凈” ,不至于造成對磁心分選的誤判。 為了滿足多路通信整機的小型化和穩定性要求, 必須生產低損耗高穩定磁心。上世紀 70 年代初,1409 所和四機部、郵電部各廠,從工藝上改變了推板空氣窯燒結,出窯后經真空罐冷卻的落后方式,改用真空爐,并控制燒結、冷卻氣氛。技術上采用共沉淀法攻關試制出了μQ乘積 60 萬和 100 萬的低損耗高穩定材料,在此基礎上,還實現了高μ7000~10000材料的突破,從而大大縮短了與國外企業的技術差異。當時正處于通信技術由FDM(頻率劃分調制)向PCM(脈沖編碼調制) 轉換時期, 日本人明石雅夫發表了μQ乘積125 萬為 0.8×10 ,100KHz)的超優鐵氧體材料<3>,其磁滯系數降為優鐵
上傳時間: 2013-12-15
上傳用戶:天空說我在
Addfilter is a command-line application which adds and removes filter drivers for a given drive or volume. It is intended to demonstrate how to insert a filter driver into the driver stack of a device. The sample illustrates how to do this by using the SetupDi APIs. The sample works on both x86 and Alpha platforms. It has only been tested in a 32-bit environment. Since Addfilter is not a driver, it does not deal with Plug and Play or Power Management.
標簽: command-line application Addfilter drivers
上傳時間: 2013-12-30
上傳用戶:天誠24
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.
標簽: Description Randomness Attribute Filtered
上傳時間: 2015-04-10
上傳用戶:ynzfm
Description: S-ISOMAP is a manifold learning algorithm, which is a supervised variant of ISOMAP. Reference: X. Geng, D.-C. Zhan, and Z.-H. Zhou. Supervised nonlinear dimensionality reduction for visualization and classification. IEEE Transactions on Systems, Man, and Cybernetics - Part B: Cybernetics, 2005, vol.35, no.6, pp.1098-1107.
標簽: Description supervised algorithm S-ISOMAP
上傳時間: 2015-04-10
上傳用戶:wfeel
mp3設計程序資料,采用c語言編寫。 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
上傳時間: 2015-04-13
上傳用戶:小碼農lz
A command-line file compression utility for Windows NT. It allows you to select files for NTFS file compression based on file name (with wild- cards), minimum file size, and/or a minimum compression ratio. You can also specify file extensions of files to be ignored. With C++ src
標簽: command-line compression for Windows
上傳時間: 2015-08-27
上傳用戶:xjz632