One of my project needs to save test results to different Access database files for different units to be tested. The database files’ name is automatic generated based on UUT’s serial number. Currently, I’m using the LabVIEW Database Connectivity Toolset, and the default method to access a database file by it is UDL file. The UDL file contains only one static database file and it is quite hard to change it programmly without manually select a database file and click the confirm button. And it will be a nightmare to create each UDL file for each UUT before the test is taken.
To change the UDL file’s content in LabVIEW programmly is not easy too. Because UDL file is unicode-formatted, and LabVIEW is quite limited in support to unicode. I had tried several ways to change the database file name in UDL file and save the UDL file to hard disk. And when I open the changed UDL again, I got “File corrupted” message. It seemed that it is not a good way. Read more…
LabVIEW
Access, Database Connectivity Toolset, LabVIEW, UDL file
LabVIEW 8.x comes with the User Interface Event Handler template by default to process user interface events. But in some complicated applications, there will be so many jobs to do at the same time, and this default template is not enough. For example, in one of my projects, UUT’s power supply monitor and serial communication with UUT is running all the time while some tests are performed. If only with the default template in this case, the user interface will freeze when the application is performing some time-consuming jobs like serial communication or DAQ.
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LabVIEW
LabVIEW, Program Structure, Queue, State Machine, Template, User Interface
In one of my project, I’ll use a bar graph to display a 1D array. In the plot legend, I changed the plot properties and set one of the bar plots. But when I finished, the graph showed as bar plot but it joined the values of the plot with lines. I did not want the lines, after tried for a few times, I got what I want. The detail of how-to is as follows:
First, click on the Plot Legend, select ‘Common Plots’ and then the bottom right option from the drop down list.
Second, select ‘Bar Plots’ lower down in the plot menu, make the appearance change.
Last, in the ‘Interpolation’ menu specifically select the first item(the top-left one, which has no lines).
And after that, job get done.
LabVIEW
Array, Bar Graph, LabVIEW