IviSwtch Class Driver Overview
This instrument driver provides programming support for the IviSwtch Class. The IviSwtch class driver conceptualizes a switch as an instrument that can establish a connection between two I/O channels. The IviSwtch class driver can support instruments that can perform triggered scanning (trigger-synchronized establishing or breaking of the paths). The driver contains all the functions required in IviSwtch specification defined by the IVI Foundation and VXIplug&play Systems Alliance. This driver requires NI-VISA and the IVI Compliance Package to be installed.
An IviSwtch is a vendor-defined switch module with a series of I/O capable channels. These channels can then be connected through the internals of the switch module, where not all connections are necessarily valid. Refer to the following example figure. The IviSwtch class driver is designed to support the typical switch as well as common extended functionality found in more complex switch instruments. The IviSwtch class driver conceptualizes the switch as an instrument that can establish paths between its I/O channels.
Use this driver to develop programs that are independent of a particular switch. You can use this class driver with any switch that has an IVI instrument specific driver that is compliant with the IviSwtch class. The IviSwtch class driver accesses the specific driver for your instrument using the configuration information you supply in MAX.
The IviSwtch class driver divides instrument capabilities into a base capability group and multiple extension capability groups. The IviSwtchBase capability group supports switches able to connect and disconnect paths on the instrument, determine the connectivity of two switches, and query the state of the switch module. The functions and attributes of this group are implemented by all switch instrument drivers that are compliant with the IviSwitch class.
Extension Capability Groups
The IviSwtch class driver identifies functions and attributes that belong to an extension group with the following abbreviations. Instrument specific drivers are not required to implement any of the extension capability groups. If you use functions and attributes that belong to extension capability groups, every instrument specific driver that you use must implement those extensions.
| Group Name | Description |
|---|---|
| IviSwtchScanner | Defines extensions for instruments capable of scanning channels. |
| IviSwtchSoftwareTrigger | Defines instruments capable of receiving software triggers and implements the IviSwtchScanner extension group. |
IviSwtchScanner defines extended capabilities for switches that can wait for the trigger to establish or break paths on the switch module, and assert a trigger upon completed task. The switches that can perform such tasks are the part of the IviSwtchScanner extension group.
IviSwtchSoftwareTrigger defines extended capabilities for switches that can support IviSwtchScanner extension group and receive software triggers. The following figure illustrates a series of I/O channels connected through the switch module internals.
