Lecroy Xi series vi's

[RTSLVU]

I used to have a project style "driver" for the Lecroy Xi series, but now I can not find it...

I went to the Lecroy site and all they have for download now is an IVI driver

I do not understand how to use the IVI driver, from the looks of the examples it is something you would use in C not LabView....

Anyway does anyone have a copy of the old project style Lecroy drivers that had the vi's in it?

[RTSLVU]

Nevermind I found them...

So what is the deal with IVI drivers?

They seem insainly difficult to use for even a simple task.

Message Edited by RTSLVU on 06-08-2010 12:59 PM

[Dennis_Knutson]

Why do you think that? The IVI Scope functions on the IVI Class palette are organized much like any other specific driver. The only thing different is configuring the driver in MAX. I'll admit that I'll use a native LabVIEW driver when given a choice however, just because it's easier to edit the source code.

[RTSLVU]

I guess I do not understand how to use IVI drivers. I went to the help file that comes with it and this is the example they gave.

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This section provides step-by-step instructions for building a simple LabVIEW application with the LeCroyScope IVI-COM driver.

Accessing the LeCroyScope Driver from the Class Browser

The first step in building a LabVIEW application using an IVI-COM driver is to access the Class Browser and direct it to load the LeCroyScope IVI-COM driver. From LabVIEW's perspective, the LeCroyScope driver is simply a COM (aka "ActiveX") component. As such, it can be loaded via the ActiveX feature of the Class Browser.

To load the LeCroyScope into the Class Browser

1. From the View menu, choose Class Browser. The Class Browser window appears.
2. From the Object Library combo box at the top, choose ActiveX and then Select Type Libraries... The system will likely pause for several seconds as LabVIEW scans your system for all installed COM components.
3. From the Select Type Libraries dialog box that appears, check the checkbox labeled "IVI LeCroyScope 3.2 Type Library Version 3.2" and click OK.
4. From the Class combo box, select LeCroyScopeLib.ILeCroyScope.
5. The Properties and Methods window now displays the hierarchy of methods and properties available in the LeCroyScope driver. The items with small blue dots are interface reference properties and allow you to navigate to sub-interfaces on the driver. Double-click on one of these, such as the System interface and the Properties and Methods window is updated to display the methods and properties of the sub-interface. To navigate back to the root of the hierarchy, click on the System hyperlink in the Selected property or method textbox near the bottom.

Initializing the Driver

The two main LabVIEW primitives required to access IVI-COM driver methods and properties are the Invoke Node (for methods) and the Property Node (for properties). Conveniently, the Class Browser automatically creates and configures these nodes for you.

Before any Invoke Node or Property Node can execute on the IVI-COM driver, it must be instantiated. This is accomplished using the Automation Open VI from the ActiveX palette. The following procedure explains how to instantiate and initialize the driver.

To instantiate and initialize the the LeCroyScope driver

1. From the Class Browser, choose the Initialize node from the hierarchy displayed in the Properties and Methods window. Drag-n-drop the node onto the block diagram.
2. The Automation Open VI is used to instantiate the IVI-COM driver before executing the Initialize function. Right-click on the Initialize Invoke Node just at the top left corner at the reference input, and select ActiveX Palette and then Automation Open. This creates the Automation Open VI. Make sure the Automation Refnum output of the Automation Open VI is wired to the reference input of the Initialize Invoke Node. Also, make sure the error clusters of the two VIs are wired together.
3. The Automation Open VI requires an input control. Right-click on the Automation Refnum input of the Automation Open VI and choose Select ActiveX Class and then choose Browse.
4. From the Type Library combo box at the top, choose "LeCroyScope Version 3.2". Expand the LeCroyScope node and choose ILeCroyScope (the first interface under the expanded node). Click OK.
5. LabVIEW creates an Automation Refnum input control and wires it to the Automation Open VI. Make sure the error clusters of the two VIs are wired together.
6. At this point, the VI will not compile since some of the required inputs of the Initialize Invoke Node have not be supplied. Right-click on the ResourceName input of the Initialize Invoke Node and choose Create and then Constant. LabVIEW places a constant string on the diagram and wires it to the ResourceName input. In the string constant created, enter the appropriate VISA resource descriptor for connecting to the instrument.
7. Right-click on the IdQuery input of the Initialize Invoke Node, choose Create and then Constant. LabVIEW creates a constant boolean wired to the IdQuery input. Repeat this process with the Reset input.
8. At this point, the application is executable. LabVIEW will instantiate the LeCroyScope IVI-COM driver and call the Initialize function. However, we must properly close the IVI-COM driver. We must also have the ability to read and write driver properties. These final tasks are convered in the next sections.

[RTSLVU]

Continued....

Reading and Writing Properties

Once the driver has been instantiated with the Automation Open VI and the Initialize function executes, any method or property on the LeCroyScope driver can be invoked. The previous sections explained how to call the Initialize method. Other driver methods are accessed in precisely the same fashion.

This section explains how to read and write driver properties.

To access properties on the LeCroyScope driver

1. From the Class Browser, choose any property from the hierarchy displayed in the Properties and Methods window. Drag-n-drop the node onto the block diagram.
2. LabVIEW creates a Property Node for that property on the diagram. Wire the reference out terminal of the Initialize Invoke Node to the reference input terminal of the Property Node. Also, wire the error clusters together.
3. By default, the Property Node is configured to read a driver property, as indicated by the small arrow on the right side of the node's terminal. Right-click on the Property Node terminal and select Create and then choose Indicator. This places an output indicator on the diagram and wires it to the Property Node. This reads the value of the selected property from the driver and present it in the indicator.
4. To use a Property Node to write a property value to the driver, simply right-click on the Property Node and choose Change to Write. This reconfigures the Property Node to be a "setter" node, as indicated by the re-positioning of the small arrow to the left side of the node terminal.
5. A single Property Node can be used to read and write multiple properties. This is accomplished by resizing the Property Node vertically. Move the cursor over the node and resizing handles appear at the top and bottom of the node. Use the resizing handles to drag the border of the node down to display additional terminals.
6. To configure a specific terminal to access a particular property, right-click on a terminal and choose Select Property.... This brings up an additional Class Browser window, from which you can select the desired property. You can configure individual terminals to read or write by right-clicking the specific terminal and choosing Change To Read or Change To Write as appropriate. Note that multi-terminal Property Nodes execute in order from top to bottom.

Closing the Driver

To complete a LabVIEW application using the LeCroyScope driver, it is important to properly close the driver. If the driver is not properly closed, unexpected behavior and resource leaks could result. Moreover, it is important to understand when to close the driver. If multiple VIs within an LabVIEW application need to access the driver, the instantion and initialization of the driver is typically done in a dedicated VI as is the close operation described in this section. You generally do not open, access, and close an IVI-COM driver within a single LabVIEW VI. Nevertheless, the procedure described here applies to a single VI application and to applications that share a driver instance.

To close the LeCroyScope driver

1. From the Class Browser, choose the Close node from the hierarchy displayed in the Properties and Methods window. Drag-n-drop the node onto the block diagram.
2. Wire the reference out terminal of the last Invoke Node or Property Node in your VI to the reference input of the Close Invoke Node. Also, wire the error clusters togther.
3. Executing the Close method on the driver instructs the driver to release any resouces it is holding. It does not, however, tell LabVIEW to dispose of the driver instance. This is accomplished with the Close Reference VI.
4. Right-click on the reference out terminal of the Close Invoke Node and choose ActiveX Palette and then select Reference Close.
5. Wire the reference out terminal of the Close Invoke Node to the reference input of the Close Reference VI.
6. Your simple LabVIEW application using the LeCroyScope driver is now complete.

[Dennis_Knutson]

There are aqctually two types of IVI drivers. There are IVI-C and IVI-COM. IVI-C drivers are created with LabWindows/CVI and that is what the functions on the IVI Class Drivers palette use. The IVI-COM drivers are a standard generated by certain vendors that wanted something more comfortable to VB, etc. users. IVI-COM is no different than using the ActiveX interface of Excel for example and yes, they are a pita. Look at this about using IVI-C class drivers with IVI-COM.

[mentalstormtrooper]

I see that you already located the drivers for the LeCroy Scopes but I thought I would post a link to them anyways.

http://www.lecroy.com/Support/SoftwareDownload/LabView.aspx?capid=106&mid=533&smid=

The link takes you to a list of LabVIEW drivers for LeCroy Scopes.  The first section contains links to the IVI drivers.  The second section has the link (goes to NI site) for the "Plug n Play" drivers (not IVI). The rest of the page has links for drivers for different scope models.