# MTCMS Library Enumerations and Structures

The MTCMS Library uses the following constants and data structures.

#### MTConnectionType Values <a href="#id-6.1_mtconnectiontype_values" id="id-6.1_mtconnectiontype_values"></a>

Device connection types:

```
enum MTConnectionType
{
        USB, IP,
                Serial
};
```

#### MTConnectionState Values

Device connection states:

<pre><code>enum MTConnectionState
{
<strong>    Disconnected, 
</strong><strong>    Connecting,
</strong><strong>    Error, 
</strong><strong>    Connected, 
</strong><strong>    Disconnecting
</strong>};
</code></pre>

#### MTDeviceInformation

Device information structure:

```
struct MTDeviceInformation
{
    const char* Id; 
    const char* Name; 
    const char* Address;
    const char* ProductId;
};
```

#### MTCMSMessage

MTCMSMessage structure:

```
struct MTCMSMessage
{
    int messageType; 
    int applicationID; 
    int commandID;
    int resultCode; 
    int dataTag;
    const unsigned char* data; 
    int dataLength;
    const unsigned char* messageBytes; 
    int messageBytesLength;
};
```


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