MTConnect Device File is an XML file (XML as of v2.0) that provides the structure and semantics for any given device(s) complying with the MTConnect Information Model.
One of the configuration parameters for a C++ Agent is Devices where you specify the XML MTConnect Device File for your piece of equipment.
Any data source can be a device in the MTConnect. Common devices are CNC machines, 3d printers, robot arms, controls, sensors or sensor controllers, smart tools, etc.
Throughout the examples below, the content will be referred to the MTConnect SysML Model. So that the reader can explore and understand all the related properties which may or may not be mentioned in the examples below.
For the simplest possible device, we are modeling a linux CNC that has only Availability, AssetChanged and AssetRemoved dataitems. These are the minimum required set of dataitems for any given Device in MTConnect. See the definition in the MTConnect model here: Device
It is important to note that all the ids in a Device file MUST be unique. As a best practice, all the names are also kept unique. ids and names of the same element might be the same as can be seen below (example: for ASSET_CHANGED)
<Devices>
<Device uuid="linux-01" name="linuxCNC">
<DataItems>
<DataItem type="AVAILABILITY" id="a1" name="avail" category="EVENT"/>
<DataItem type="ASSET_CHANGED" id="asset_chg1" name="asset_chg1" category="EVENT"/>
<DataItem type="ASSET_REMOVED" id="asset_rem1" name="asset_rem1" category="EVENT"/>
</DataItems>
</Device>
</Devices>
As you can see in the example above, all devices in a device file are modeled under Devices and similarly all dataitems are modeled under DataItems. Other similar examples include Components, Compositions and References to name a few. These are called organizers and their main purpose is to organize similar element types within.
A Device is a Component type and inherits all the properties and adds/modifies a distinct few.
See the model here to learn about all properties that a Component may have here: Component and Component Diagram.
Learn about the properties of a DataItem here: DataItem.
If you are already familiar with XML and XML schemas, please find the latest MTConnectDevices schema here to write your Device File. As of 9th June 2022, MTConnectDevices_2.0.xsd are the latest schema for MTConnect Devices.
You can also validate your XML Device file online against the above mentioned or whatever is the latest MTConnectDevices schema. There are various free tools online where you can just upload your Device file and the schema for validation.