Extract interface numbers into enums.
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                        dfuMANIFEST                  = 7,
                        dfuMANIFEST_WAIT_RESET       = 8,
                        dfuUPLOAD_IDLE               = 9,
-                       dfuERROR                         = 10
+                       dfuERROR                     = 10
                };
 
                /** DFU command status error codes. Refer to the DFU class specification for information on each error code. */
                        errUSBR                      = 12,
                        errPOR                       = 13,
                        errUNKNOWN                   = 14,
-                       errSTALLEDPKT                = 15
+                       errSTALLEDPKT                = 15
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_DFU,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 0,
 
                        USB_Descriptor_DFU_Functional_t       DFU_Functional;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_DFU = 0, /**< DFU interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Printer,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Generic HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_VendorHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Printer = 0, /**< Printer interface descriptor ID */
+               };
+
        /* Macros: */
                /** Endpoint address of the HID data IN endpoint. */
                #define HID_IN_EPADDR                (ENDPOINT_DIR_IN | 1)
 
        {
                .Config =
                        {
-                               .InterfaceNumber           = 0,
+                               .InterfaceNumber           = INTERFACE_ID_MassStorage,
                                .DataINEndpoint            =
                                        {
                                                .Address           = MASS_STORAGE_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             MS_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MassStorage = 0, /**< Mass storage interface descriptor ID */
+               };
+
        /* Function Prototypes: */
                uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
                                                    const uint8_t wIndex,
 
        {
                .Config =
                        {
-                               .InterfaceNumber          = 0,
+                               .InterfaceNumber          = INTERFACE_ID_Printer,
                                .DataINEndpoint           =
                                        {
                                                .Address          = PRINTER_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_Printer,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             Printer_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each string descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Printer      = 0, /**< Printer interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
-                               .StreamingInterfaceNumber = 1,
+                               .ControlInterfaceNumber   = INTERFACE_ID_AudioControl,
+                               .StreamingInterfaceNumber = INTERFACE_ID_AudioStream,
                                .DataINEndpoint           =
                                        {
                                                .Address          = AUDIO_STREAM_EPADDR,
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 1,
 
                        .TotalEndpoints           = 1,
 
                        USB_Audio_Descriptor_StreamEndpoint_Spc_t Audio_StreamEndpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
-                               .StreamingInterfaceNumber = 1,
+                               .ControlInterfaceNumber   = INTERFACE_ID_AudioControl,
+                               .StreamingInterfaceNumber = INTERFACE_ID_AudioStream,
                                .DataOUTEndpoint          =
                                        {
                                                .Address          = AUDIO_STREAM_EPADDR,
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 1,
 
                        .TotalEndpoints           = 1,
 
                        USB_Audio_Descriptor_StreamEndpoint_Spc_t Audio_StreamEndpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC1_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC1_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 2,
+                       .InterfaceNumber        = INTERFACE_ID_CDC2_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 3,
+                       .InterfaceNumber        = INTERFACE_ID_CDC2_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC2_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC1_CCI = 0, /**< CDC1 CCI interface descriptor ID */
+                       INTERFACE_ID_CDC1_DCI = 1, /**< CDC1 DCI interface descriptor ID */
+                       INTERFACE_ID_CDC2_CCI = 2, /**< CDC2 CCI interface descriptor ID */
+                       INTERFACE_ID_CDC2_DCI = 3, /**< CDC2 DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC1_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC1_TX_EPADDR,
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 2,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC2_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC2_TX_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_GenericHID,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Generic HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_GenericHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_GenericHID = 0, /**< GenericHID interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_GenericHID,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = GENERIC_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Joystick,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Joystick = 0, /**< Joystick interface desciptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_Joystick,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = JOYSTICK_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Keyboard = 0, /**< Keyboard interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_Keyboard,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = KEYBOARD_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x01,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        break;
                case HID_DTYPE_HID:
-                       if (!(wIndex))
+                       switch (wIndex)
                        {
-                               Address = &ConfigurationDescriptor.HID1_KeyboardHID;
-                               Size    = sizeof(USB_HID_Descriptor_HID_t);
-                       }
-                       else
-                       {
-                               Address = &ConfigurationDescriptor.HID2_MouseHID;
-                               Size    = sizeof(USB_HID_Descriptor_HID_t);
+                               case INTERFACE_ID_Keyboard:
+                                       Address = &ConfigurationDescriptor.HID1_KeyboardHID;
+                                       Size    = sizeof(USB_HID_Descriptor_HID_t);
+                                       break;
+                               case INTERFACE_ID_Mouse:
+                                       Address = &ConfigurationDescriptor.HID2_MouseHID;
+                                       Size    = sizeof(USB_HID_Descriptor_HID_t);
+                                       break;
                        }
 
                        break;
                case HID_DTYPE_Report:
-                       if (!(wIndex))
+                       switch (wIndex)
                        {
-                               Address = &KeyboardReport;
-                               Size    = sizeof(KeyboardReport);
-                       }
-                       else
-                       {
-                               Address = &MouseReport;
-                               Size    = sizeof(MouseReport);
+                               case INTERFACE_ID_Keyboard:
+                                       Address = &KeyboardReport;
+                                       Size    = sizeof(KeyboardReport);
+                                       break;
+                               case INTERFACE_ID_Mouse:
+                                       Address = &MouseReport;
+                                       Size    = sizeof(MouseReport);
+                                       break;
                        }
 
                        break;
 
                        USB_Descriptor_Endpoint_t             HID2_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Keyboard = 0, /**< Keyboard interface descriptor ID */
+                       INTERFACE_ID_Mouse    = 1, /**< Mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_Keyboard,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = KEYBOARD_IN_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber              = 1,
+                               .InterfaceNumber              = INTERFACE_ID_Mouse,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = MOUSE_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_KeyboardAndMouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_KeyboardAndMouse = 0, /**< Combined keyboard and mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_KeyboardAndMouse,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = HID_IN_EPADDR,
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_MidiAudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_MidiAudioStreaming,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 2,
 
                        USB_MIDI_Descriptor_Jack_Endpoint_t       MIDI_Out_Jack_Endpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MidiAudioControl   = 0, /**< MIDI audio control interface descriptor ID */
+                       INTERFACE_ID_MidiAudioStreaming = 1, /**< MIDI audio streaming interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .StreamingInterfaceNumber = 1,
+                               .StreamingInterfaceNumber = INTERFACE_ID_MidiAudioStreaming,
                                .DataINEndpoint           =
                                        {
                                                .Address          = MIDI_STREAM_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             MS_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MassStorage = 0, /**< Mass storage interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber           = 0,
+                               .InterfaceNumber           = INTERFACE_ID_MassStorage,
                                .DataINEndpoint            =
                                        {
                                                .Address           = MASS_STORAGE_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
 
                USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MassStorage = 0, /**< Mass storage interface descriptor ID */
+                       INTERFACE_ID_Keyboard    = 1, /**< Keyboard interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber           = 0,
+                               .InterfaceNumber           = INTERFACE_ID_MassStorage,
                                .DataINEndpoint            =
                                        {
                                                .Address           = MASS_STORAGE_IN_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber              = 1,
+                               .InterfaceNumber              = INTERFACE_ID_Keyboard,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = KEYBOARD_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Mouse HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_MouseHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Mouse = 0, /**< Mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_Mouse,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = MOUSE_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             RNDIS_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC_TX_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 2,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                MS_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI     = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI     = 1, /**< CDC DCI interface descriptor ID */
+                       INTERFACE_ID_MassStorage = 2, /**< Mass storage interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber                = 2,
+                               .InterfaceNumber                = INTERFACE_ID_MassStorage,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = MASS_STORAGE_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 2,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
 
                USB_Descriptor_Endpoint_t                HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+                       INTERFACE_ID_Mouse   = 2, /**< Mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber                = 2,
+                               .InterfaceNumber                = INTERFACE_ID_Mouse,
                                .ReportINEndpoint               =
                                        {
                                                .Address                = MOUSE_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_TestAndMeasurement,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 3,
 
                        USB_Descriptor_Endpoint_t             TM_NotificationEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_TestAndMeasurement = 0, /**< Test and measurement interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 1,
 
                        .TotalEndpoints           = 1,
 
                        USB_Audio_Descriptor_StreamEndpoint_Spc_t Audio_StreamEndpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 1,
 
                        .TotalEndpoints           = 1,
 
                        USB_Audio_Descriptor_StreamEndpoint_Spc_t Audio_StreamEndpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC1_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC1_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 2,
+                       .InterfaceNumber        = INTERFACE_ID_CDC2_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 3,
+                       .InterfaceNumber        = INTERFACE_ID_CDC2_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC2_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC1_CCI = 0, /**< CDC1 CCI interface descriptor ID */
+                       INTERFACE_ID_CDC1_DCI = 1, /**< CDC1 DCI interface descriptor ID */
+                       INTERFACE_ID_CDC2_CCI = 2, /**< CDC2 CCI interface descriptor ID */
+                       INTERFACE_ID_CDC2_DCI = 3, /**< CDC2 DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_GenericHID,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 2,
 
                        // Generic HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_GenericHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
-               USB_Descriptor_Endpoint_t             HID_ReportOUTEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportOUTEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_GenericHID = 0, /**< GenericHID interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Joystick,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Joystick HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_JoystickHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Joystick = 0, /**< Joystick interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 2,
 
                        // Keyboard HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_KeyboardHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
-               USB_Descriptor_Endpoint_t             HID_ReportOUTEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportOUTEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Keyboard = 0, /**< Keyboard interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x01,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        break;
                case HID_DTYPE_HID:
-                       if (!(wIndex))
+                       switch (wIndex)
                        {
-                               Address = &ConfigurationDescriptor.HID1_KeyboardHID;
-                               Size    = sizeof(USB_HID_Descriptor_HID_t);
-                       }
-                       else
-                       {
-                               Address = &ConfigurationDescriptor.HID2_MouseHID;
-                               Size    = sizeof(USB_HID_Descriptor_HID_t);
+                               case (INTERFACE_ID_Keyboard):
+                                       Address = &ConfigurationDescriptor.HID1_KeyboardHID;
+                                       Size    = sizeof(USB_HID_Descriptor_HID_t);
+                                       break;
+                               case (INTERFACE_ID_Mouse):
+                                       Address = &ConfigurationDescriptor.HID2_MouseHID;
+                                       Size    = sizeof(USB_HID_Descriptor_HID_t);
+                                       break;
                        }
                        break;
                case HID_DTYPE_Report:
-                       if (!(wIndex))
+                       switch (wIndex)
                        {
-                               Address = &KeyboardReport;
-                               Size    = sizeof(KeyboardReport);
-                       }
-                       else
-                       {
-                               Address = &MouseReport;
-                               Size    = sizeof(MouseReport);
+                               case INTERFACE_ID_Keyboard:
+                                       Address = &KeyboardReport;
+                                       Size    = sizeof(KeyboardReport);
+                                       break;
+                               case INTERFACE_ID_Mouse:
+                                       Address = &MouseReport;
+                                       Size    = sizeof(MouseReport);
+                                       break;
                        }
 
                        break;
 
                        USB_Descriptor_Endpoint_t             HID2_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Keyboard = 0, /**< Keyboard interface descriptor ID */
+                       INTERFACE_ID_Mouse    = 1, /**< Mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 2,
 
                        USB_MIDI_Descriptor_Jack_Endpoint_t       MIDI_Out_Jack_Endpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             MS_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MassStorage = 0, /**< Mass storage interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Mouse HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_MouseHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Mouse = 0, /**< Mouse interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t             RNDIS_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Mouse,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Mouse HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_MouseHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Mouse = 0, /**< Mouse interface descriptor ID (must be zero) */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber            = 0,
+                               .InterfaceNumber            = INTERFACE_ID_Mouse,
                                .ReportINEndpoint           =
                                        {
                                                .Address            = MOUSE_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_AVRISP,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                AVRISP_DataOutEndpoint;
                } AVRISP_USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AVRISP = 0, /**< AVRISP interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum AVRISP_StringDescriptors_t
                {
-                   AVRISP_STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   AVRISP_STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   AVRISP_STRING_ID_Product       = 2, /**< Product string ID */
-                   AVRISP_STRING_ID_Serial        = 3, /**< Serial number string ID */
+                       AVRISP_STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       AVRISP_STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       AVRISP_STRING_ID_Product      = 2, /**< Product string ID */
+                       AVRISP_STRING_ID_Serial       = 3, /**< Serial number string ID */
                };
 
        /* External Variables: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC_TX_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC_TX_EPADDR,
 
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 0,
+                       .InterfaceNumber          = INTERFACE_ID_AudioControl,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 0,
                {
                        .Header                   = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber          = 1,
+                       .InterfaceNumber          = INTERFACE_ID_AudioStream,
                        .AlternateSetting         = 0,
 
                        .TotalEndpoints           = 2,
 
                        USB_MIDI_Descriptor_Jack_Endpoint_t       MIDI_Out_Jack_Endpoint_SPC;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_AudioControl = 0, /**< Audio control interface descriptor ID */
+                       INTERFACE_ID_AudioStream  = 1, /**< Audio stream interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .StreamingInterfaceNumber = 1,
+                               .StreamingInterfaceNumber = INTERFACE_ID_AudioStream,
                                .DataINEndpoint           =
                                        {
                                                .Address          = MIDI_STREAM_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_Keyboard,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Keyboard HID Interface
                        USB_Descriptor_Interface_t            HID_Interface; /**< Keyboard interface descriptor */
                        USB_HID_Descriptor_HID_t              HID_KeyboardHID; /**< Keyboard HID descriptor */
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint; /**< Keyboard key report endpoint descriptor */
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint; /**< Keyboard key report endpoint descriptor */
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_Keyboard = 0, /**< Keyboard interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber            = 0,
+                               .InterfaceNumber            = INTERFACE_ID_Keyboard,
                                .ReportINEndpoint           =
                                        {
                                                .Address            = KEYBOARD_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0x00,
+                       .InterfaceNumber        = INTERFACE_ID_HID,
                        .AlternateSetting       = 0x00,
 
                        .TotalEndpoints         = 1,
 
                        // Media Controller HID Interface
                        USB_Descriptor_Interface_t            HID_Interface;
                        USB_HID_Descriptor_HID_t              HID_MediaControlHID;
-               USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
+                       USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_HID = 0, /**< HID interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Macros: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber              = 0,
+                               .InterfaceNumber              = INTERFACE_ID_HID,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = MEDIACONTROL_HID_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_RelayBoard,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 0,
 
                        USB_Descriptor_Interface_t            RelayBoardInterface;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_RelayBoard = 0, /**< Relay board interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
-                   STRING_ID_Serial        = 3, /**< Serial number string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
+                       STRING_ID_Serial       = 3, /**< Serial number string ID */
                };
 
        /* Function Prototypes: */
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber   = 0,
+                               .ControlInterfaceNumber   = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint           =
                                        {
                                                .Address          = CDC_TX_EPADDR,
 
 #ifndef _SERIALTOLCD_H_
 #define _SERIALTOLCD_H_
 
-    /* Includes: */
-        #include <avr/io.h>
-        #include <avr/wdt.h>
-        #include <avr/interrupt.h>
-        #include <avr/power.h>
+       /* Includes: */
+               #include <avr/io.h>
+               #include <avr/wdt.h>
+               #include <avr/interrupt.h>
+               #include <avr/power.h>
 
-        #include "Descriptors.h"
+               #include "Descriptors.h"
                #include "Lib/HD44780.h"
 
-        #include <LUFA/Version.h>
-        #include <LUFA/Drivers/Misc/RingBuffer.h>
-        #include <LUFA/Drivers/USB/USB.h>
+               #include <LUFA/Version.h>
+               #include <LUFA/Drivers/Misc/RingBuffer.h>
+               #include <LUFA/Drivers/USB/USB.h>
                #include <LUFA/Platform/Platform.h>
 
        /* Macros: */
                #define COMMAND_ESCAPE     0x1B
 
-    /* Function Prototypes: */
-        void SetupHardware(void);
+       /* Function Prototypes: */
+               void SetupHardware(void);
 
-        void EVENT_USB_Device_ConfigurationChanged(void);
-        void EVENT_USB_Device_ControlRequest(void);
+               void EVENT_USB_Device_ConfigurationChanged(void);
+               void EVENT_USB_Device_ControlRequest(void);
 
 #endif
 
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_HID,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
 
                        USB_Descriptor_Endpoint_t             HID_ReportINEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_MassStorage = 0, /**< Mass storage interface descriptor ID */
+                       INTERFACE_ID_HID         = 1, /**< HID interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .InterfaceNumber           = 0,
+                               .InterfaceNumber           = INTERFACE_ID_MassStorage,
                                .DataINEndpoint            =
                                        {
                                                .Address           = MASS_STORAGE_IN_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber              = 1,
+                               .InterfaceNumber              = INTERFACE_ID_HID,
                                .ReportINEndpoint             =
                                        {
                                                .Address              = GENERIC_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 2,
+                       .InterfaceNumber        = INTERFACE_ID_MassStorage,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t              MS_DataOutEndpoint;
                } USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI     = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI     = 1, /**< CDC DCI interface descriptor ID */
+                       INTERFACE_ID_MassStorage = 2, /**< Mass storage interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum StringDescriptors_t
                {
-                   STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   STRING_ID_Product       = 2, /**< Product string ID */
+                       STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,
        {
                .Config =
                        {
-                               .InterfaceNumber                = 2,
+                               .InterfaceNumber                = INTERFACE_ID_MassStorage,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = MASS_STORAGE_IN_EPADDR,
 
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 0,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_CCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 1,
                {
                        .Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},
 
-                       .InterfaceNumber        = 1,
+                       .InterfaceNumber        = INTERFACE_ID_CDC_DCI,
                        .AlternateSetting       = 0,
 
                        .TotalEndpoints         = 2,
 
                        USB_Descriptor_Endpoint_t                CDC_DataInEndpoint;
                } USART_USB_Descriptor_Configuration_t;
 
+               /** Enum for the device interface descriptor IDs within the device. Each interface descriptor
+                *  should have a unique ID index associated with it, which can be used to refer to the
+                *  interface from other descriptors.
+                */
+               enum USART_InterfaceDescriptors_t
+               {
+                       INTERFACE_ID_CDC_CCI = 0, /**< CDC CCI interface descriptor ID */
+                       INTERFACE_ID_CDC_DCI = 1, /**< CDC DCI interface descriptor ID */
+               };
+
                /** Enum for the device string descriptor IDs within the device. Each string descriptor should
                 *  have a unique ID index associated with it, which can be used to refer to the string from
                 *  other descriptors.
                 */
                enum USART_StringDescriptors_t
                {
-                   USART_STRING_ID_Language      = 0, /**< Supported Languages string descriptor ID (must be zero) */
-                   USART_STRING_ID_Manufacturer  = 1, /**< Manufacturer string ID */
-                   USART_STRING_ID_Product       = 2, /**< Product string ID */
+                       USART_STRING_ID_Language     = 0, /**< Supported Languages string descriptor ID (must be zero) */
+                       USART_STRING_ID_Manufacturer = 1, /**< Manufacturer string ID */
+                       USART_STRING_ID_Product      = 2, /**< Product string ID */
                };
 
        /* Function Prototypes: */
                uint16_t USART_GetDescriptor(const uint16_t wValue,
                                             const uint8_t wIndex,
                                             const void** const DescriptorAddress,
-                                                                        uint8_t* const DescriptorMemorySpace);
+                                            uint8_t* const DescriptorMemorySpace);
 
 #endif
 
 
        {
                .Config =
                        {
-                               .ControlInterfaceNumber         = 0,
+                               .ControlInterfaceNumber         = INTERFACE_ID_CDC_CCI,
                                .DataINEndpoint                 =
                                        {
                                                .Address                = CDC_TX_EPADDR,