【正文】 EW graphical programming language of the virtual instrument programming methods and technology. 1 Virtual Oscilloscope structure and position of The virtual digital oscilloscope PCI bus by a multifunction data acquisition card and the corresponding software. They are installed on a PC running the Windows95/98/NT machine (remended configuration in PENTIUM Ⅱ / 233 and above), which constitute a powerful digital oscilloscope can be stored. Data Acquisition Card PCI bus transfer rate of highdata throughput large future data acquisition board design mainstream. The design uses the PCI1200 data acquisition card is a better value for money products, support DMA mode and dualbuffer mode, ensuring the uninterrupted realtime signal acquisition and storage. It supports a unipolar and bipolar analog signal input, signal input in the range of 5 ~ +5 V and 0 ~ 10V. Provide 16 singleended / 8 differential analog input channels, 2 independent DA output channels, 24line TTL digital I / O, 3 16bit timer counters, such as multiple functions. These features allow us not only can use the card design virtual oscilloscope, but also can design a virtual function generator or virtual counter, to achieve a multipurpose card. Of course, limited to funding conditions, we chose the PCI1200 card sampling rate can only be reached 100kS / s, the actual Oscilloscopes, this much can not meet the signal bandwidth requirements. Currently on the market sampling rate up to 200MS / s of PCI data acquisition card has been a mature product, the technical realization of highbandwidth virtual oscilloscope problem does not exist. When the actual measurement input signal through the BNC connector from the input data acquisition card to enter the collection. Instrument Function The virtual digital oscilloscope design reference to HP39。 虛擬面板即用戶界面 , 是用戶與儀器交流 信息的橋梁。儀器硬件主要負責信號調理和模數(shù)轉換 , 通過 PC總線與計算機進行數(shù)據(jù)交換。TG8 文獻標識碼 A 文章編號 1009一 4334(2021)03一 0086一 03 一、引言 儀器儀表長期以來在實驗科學中占據(jù)著十分重要的地位 , 儀器儀表也是我們進行物理教學 ,開展物理實驗的一個重要基礎。s customers do not understand the acquisition card interface circuit and principles of the instrument can be modified or expanded features. Measuring the parameters of modular software structure, is a reasonable division of the measurement modules, and enhance the use of mon parts of the general, and to provide the parameters of the plex graphics and tables output. Calibration and error correction module, not only on the sensor can be calibrated to amend the source of error, but also the use of the average, and so on the relevant calculation of inhibition and to reduce interference and improve the measurement accuracy and increase the reliability of measurement. The apparatus of the software used NI39。 二、儀器構成和工作原理 用一臺儀器完成多個參數(shù)的測量一直是測試領域的一個實際問題 , 用傳統(tǒng)儀器往往很難實現(xiàn)。 16位的 A/D完全可滿足這一要求 。 digital oscilloscope。 in memory state, the maximum memory display A, B twochannel input signal 17 waveform (A memory channel can display 16 Group signal data, Bchannel memory can only show 1 signal data). In practice, memory display the main signal used to measure jitter or a parative analysis of two or more of the signal waveform. This article describes a virtual digital oscilloscope desktop not only has the general function of digital storage oscilloscope, and give full play to a powerful puter and software design flexibility, the main technical characteristics of the performance in the following: oriented programming techniques, software development, high efficiency, good operability and maintainability。一方面，目前我國高檔臺式儀器如數(shù)字示波器、頻譜分析儀、邏輯分析儀等還主要依賴進口，這些儀器加工工藝復雜、對制造水平要求高，生產突破有困難，采用虛 擬儀器技術可以通過只采購必要的通用數(shù)據(jù)采集硬件來設計自己的儀器系統(tǒng)；另一方面，用戶可以將一些先進的數(shù)字信號處理算法應用于虛擬儀器設計，提供傳統(tǒng)臺式儀器不具備的功能，而且完全可以通過軟件配置實現(xiàn)多功能集成的儀器設計。儀器主要功能包括：雙通道信號輸入、觸發(fā)控制、通道控制、時基控制、波形顯示、參數(shù)自動測量 、頻譜分析、波形存儲和回放等。 波形顯示模塊 軟件提供了三種波形顯示模式： 處于正常狀態(tài)時，最多只能顯示 A、 B 兩通道輸入的 2 個信號的波形；處于記憶狀態(tài)時，最多可以記憶顯示 A、 B 兩通 道輸入的 17 個信號的波形（ A 通道可記憶顯示 16 組信號數(shù)據(jù)， B 通道只能記憶顯示１組信號數(shù)據(jù)）。從軟盤或硬盤上讀取的數(shù)據(jù)同實時采集的數(shù)據(jù)一樣，能夠進行自動參數(shù)測量以及顯示波形并保留在顯示窗口（顯示模式可以設置為三種模式中的任意一種），還可以根據(jù)需要設置進行頻譜分析。其中： 當然，限于經(jīng)費條 件，我們選擇的 PCI－ 1200 卡的采樣速率只能達到 100kS／ s，對實際示波器而言，這遠不能滿足信號帶寬的要求。 傳統(tǒng)臺式儀器是由儀器廠家設計并定義好功能的一個封閉結構，它有固定的輸入／輸出接口和儀器操作面板，每種儀器實現(xiàn)一類特定的測量功能 ，并以確定的方式提供給用戶。 ? A + B AB model: When the two channels are in a gated state, use this mode to display twochannel signal algebraic sum, after the subtraction of the waveform. Parameter Measurement Module Parameter measurement module HP54603B the parameters of the main analog measurement functions, including Vrms, such as the pletion of 12 voltage and frequency parameters, cycle time parameter 7 measurement and display its results. Spectrum Analyzer Module Spectrum analysis module fast FFT algorithm, the pletion of the frequency domain signal analysis. The spectrum analyzer can be controlled include: ? Windows choice, provided the nine kinds of spectral analysis window。 五、結束語 用虛擬儀器實現(xiàn)多參數(shù)的測量能夠簡化硬件 , 極大地降低儀器的成本 , 增加測試的可靠性。 按照使用的計算機是臺式機還是便攜機 , 可選擇不同的數(shù)據(jù)采集板。 。 multiparameter measurement. Key words: TAB24。操作人員通過友好的圖形界面及圖形化編程語言控制儀器的運行 , 完成對被測試量的采集、分析、判斷、顯示、存儲及數(shù)據(jù)生成。為覆蓋較大測量范圍并滿足一定的測量精度 , 各參數(shù)選用不同測量范圍的多只傳感器。 各參數(shù)測量軟件采用模塊化結構 , 既合理劃分各測量模塊 , 又增強采用公用部分的通用性 , 并提供復雜參數(shù)的圖形和表格輸出功能。 ? Timebased control of the main control acquisition card scanning rate, each channel scanning frequency (sampling number). Waveform Display M