1、外文资料（一）： Labview programming The pressure switch test system, involving an important concept: the virtual instrument. Virtual instrument is the United States National Instruments Corporation (NI) out of the concept of modern computer technology and instrumentation technology in-depth integration of
2、the product. Virtual Instrument virtual There are two levels of meaning: 1. A virtual control panel, two virtual test and measurement and analysis. Virtual instrument is characterized by high-performance, scalability strong little development time, seamless integration. NIs withdrawal from a profess
3、ional graphical programming software to design and development of virtual instruments, that is, Labiew. LabVIEW, short for Laboratory Virtual Instrument Engineering Workbench, is a programming environment in which you create programs using a graphical notation (connecting functional nodes via wires
4、through which data flows)； in this regard, it differs from traditional programming languages like C, C+, or Java, in which you program with text. However, LabVIEW is much more than a programming language. It is an interactive program development and execution system designed for people, like scienti
5、sts and engineers, who need to program as part of their jobs. The LabVIEW development environment works on computers running Windows, Mac OS X, or Linux. LabVIEW can create programs that run on those platforms, as well as Microsoft Pocket PC, Microsoft Windows CE, Palm OS, and a variety of embedded
6、platforms, including Field Programmable Gate Arrays (FPGAs), Digital Signal Processors (DSPs), and microprocessors. Using the very powerful graphical programming language that many LabVIEW users affectionately call G (for graphical), LabVIEW can increase your productivity by orders of magnitude. Pro
7、grams that take weeks or months to write using conventional programming languages can be completed in hours using LabVIEW because it is specifically designed to take measurements, analyze data, and present results to the user. And because LabVIEW has such a versatile graphical user interface and is
8、so easy to program with, it is also ideal for simulations, presentation of ideas, general programming, or even teaching basic programming concepts. Labiew feature continuously enriched and powerful, Labiew used for data acquisition and control, data analysis and data representation, so that engineer
9、s and scientists to take full advantage of PC functions, quickly and easily complete their own power to make. Labview main features can be summarized as follows: a graphical environment for two instruments into a built-in program compiler, so that run faster three flexible means of four supports mul
10、tiple debugging platform 5 supports DDE functions. Labiew years of development from 1986 to now, has launched a number of different versions that can support multiple popular operating systems, Labview main course of development are as follows: 1.1983 years in April, Labview Development System in th
11、e United States Austin, Texas, the successful development of 2.1985-year in May, NI introduced the Labview Beta test version 3.1986-year in October, NI company officially released the Labview1.0 for Macintosh version of the 4.1990-year in January, Labview2.0 came 5.1992-year in August in support of
12、SUN Solaris workstation and PC-Labview version available 6.1993-year in January, Labview3.0 version is developed 7.1998-year in February, Labview5.0 version available, this version is a milestone in the history of Labview 8.2003 years, Labview7Express and Labview 7 Series start into the market, in t
13、he Labview 7 series, introduced a new data type - Dynamic Data Types 9.2005 years, Labview 8 version of the interview, the version of the specific distributed, intelligent outstanding features 10.2006, the 20th anniversary edition of Labview 8.20 an interview. 8.21 is the Chinese version of 11.2007-
14、year in August, Labview8.5 available 12.2008-year in August, Labview8.6 version available After 20 years of continuous innovation, development, Labview to rely on the concept of a new and unique advantages, and has maintained an efficient and powerful, and open the three basic characteristics, and g
15、radually become the industry standard. The above describes the characteristics of Labview and development, described below how the kind of virtual instrument design Typically, a virtual instrument design steps are as follows: (1). In the design window, place the front panel controls, front panel usi
16、ng the tool template development window, the corresponding tools, from the control template and place a good access control is needed to carry out parameter setting control properties, stickers text description tag. (2). In the flow chart editing window, place the nodes, frame, in the flow chart edi
17、ting window, use the tool template corresponding tools, from a functional template and put a good access to the required icon, they are the flow chart in the nodes , frame. (3). The data flow programming, data flow using the connection tool according to the direction of the port, node, frame in turn
18、 connected to data from the source sent to the prescribed purpose terminal operating mode. (4). Run test, when the completion of step (a), (2), (3), the front panel procedure and flow chart graphic design program is completed, a virtual instrument has been basically established, whether to achieve t
19、he desired functionality, need to run the test. There are two kinds of test methods. a. Simulation Test: do not use I / O interface hardware. I needed to run tests on the signal data is from array or signal-generating function, resulting emulation signal. b. Measured test: it is through the I / O in
20、terface to hardware devices, gathering input standard signal, to test the virtual instrument capabilities. Simulation test in experimental tests carried out prior to the virtual instrument unique advantage because of its repeated testing, debugging, and constantly improve the improvement of virtual
21、instrument is extremely convenient, is a traditional instrument can not be used in test methods. (5).debugging techniques, use the toolbar shortcut Run, highlight the implementation of, Step, Breakpoint set to the following steps to program debugging. a. to identify grammatical errors, if there is a
22、 syntax error, then when start the Shortcut Bar Run button, the button becomes a broken arrow, the program can not perform. Mouse click on the button, a list will pop up an error window, the window listed in the wrong item, and then click any one of the listed errors, click the Find function button,
23、 then the error object, or the port will be changed bright. b. slow tracking program running, use the shortcut in the toolbars highlight the implementation of button, click the button, the button icon becomes highlighted form, and then click Run button, the program on a slower speed. The implementat
24、ion of the code was not grayed out after the implementation of the code highlighting, and display data on the value of the data stream. This allows the data flow, and track the implementation of the procedures. c. breakpoints and single-step, in order to check the program logic error, you may want t
25、o program a block diagram node in a node implementation. Breakpoint tool to use a certain location in the program to suspend program execution, using probes or single-step ways to view the data. d. set the probe, you can view the block diagram by setting the probe to open a connection procedure by a data value. (6). data observed, when the inspection observations were found to have an error, the mouse click Highlight Execution button, and observe the various nodes in the data stream values. (7). named Save, save the designed I.
