Table Of Contents

Open Installed Devices Session (G Dataflow)

Version:
    Last Modified: September 21, 2017

    Creates a handle to a list of installed devices supported by the specified driver. Call this node and select the name of a National Instruments instrument driver, such as NI-SCOPE, from the driver control. This node searches the system and constructs a list of all the installed devices that are supported by that driver, and returns both a handle and the number of devices found. The handle is used with other functions to query for attributes such as device name and model, and to safely discard the list when finished.

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    Note  

    This handle reflects the system state when the handle is created (that is, when you call this node). If you remove devices from the system or rename them in Measurement & Automation Explorer (MAX), this handle may not refer to an accurate list of devices. You should destroy the handle using niModInst Close Installed Devices Session and create a new handle using this node.

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    driver

    Specifies the driver whose supported devices you want to find. This string is not case-sensitive. For example, "NI-SCOPE" and "niscope" are both valid inputs.

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    Note  

    If you do not wire an input or an empty string for this parameter, session returns a list of all Modular Instruments devices installed in the system.

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    error in

    Error conditions that occur before this node runs.

    The node responds to this input according to standard error behavior.

    Standard Error Behavior

    Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

    error in does not contain an error error in contains an error
    If no error occurred before the node runs, the node begins execution normally.

    If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

    If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

    Default: No error

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    session out

    The opened NI-ModInst session. This acts as a handle to the list of installed devices and is used in other NI-ModInst functions.

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    device count

    Returns the number of devices found in the system that are supported by the driver specified in the driver parameter.

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    error out

    Error information.

    The node produces this output according to standard error behavior.

    Standard Error Behavior

    Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

    error in does not contain an error error in contains an error
    If no error occurred before the node runs, the node begins execution normally.

    If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

    If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

    Where This Node Can Run:

    Desktop OS: Windows

    FPGA: Not supported

    Web Server: Not supported in VIs that run in a web application


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