Download Digital Control Unit (DCU) Manual

Digital Control Unit
User’s Manual
The LabPro Palette is Located in the User Libraries Palette.
Express VIs and subVIs
The LabPro folder contains Express VIs and also subVIs. Express VIs were introduced in LabVIEW 7.0 to provide
an interactive means of configuring the inputs. Express VIs allow you to double click on them to bring up a dialog
box, providing you with an easy method for configuring your program. As you know, a standard subVI is configured
by the values that are wired into the subVIs connector nodes. An Express VI can also be configured in this manner.
This means Express VIs can be configured in two ways; wiring in a value or inputting a value in the Express VI’s
dialog box. If configuration values are wired, they will take precedent over values that are input into the Express
VI’s dialog box. In most cases, Express VIs will be configured in both ways, with the more important inputs
configured in the dialog box, and the less important inputs wired into the nodes. With our Express VIs you will
always be required to wire in Comm Port and the Error In, at a minimum.
The LabPro Express VIs were created by us using a special toolkit from National Instruments; you will not be able
to create your own Express VIs without having this toolkit installed. We have created a selection of Express VIs that
perform most of the major functions of the LabPro. It is possible to view the subVIs that were used to create the
Express VIs by right clicking (open-apple or command clicking on a Mac) on the Express VI and choosing Open
Front Panel. The sample DCU programs do not use all of our Express VIs. You may want to take the time to look at
the rest of these by going to the LabPro palette in the User Libraries function palette. In fact, in most examples we
have chosen not to use our Express VIs in order to keep the commands more transparent. If you are looking over our
examples, do not be confused when you see a section of code consisting of a handful of subVIs that could be
replaced by one of our Express VIs—we wanted you to see more of the details.
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