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Parent Topic: Planning a Custom Device
Custom device item properties store and communicate state information about a custom device item, such as a section or channel. Use properties to transfer configuration and state information from the configuration to the engine one time, when an operator deploys the system definition file to the target. After deployment, the engine can read properties on the target, but it cannot write properties or exchange properties with the host computer.
For example, if you are creating a custom device for third-party hardware and you need to implement a range option for the channels you will use to communicate with the hardware, you should implement the range setting as a property. You can then customize the page VIs for those channels to accept a value for range, allowing you to define the value when configuring the channels in the System Explorer window. When the custom device is deployed, NI VeriStand will read the value for range and set the range of that channel when the system definition is deployed. After it is deployed, you can no longer change the value for range.
Unlike a channel, which must be a 64-bit floating point number, a property can be any standard LabVIEW data type. However, property names are case-sensitive strings.
NI VeriStand saves property names and values with the system definition file. If you save and close the file or project, NI VeriStand retains the properties the next time you access the system definition file.