- #if defined(USB_CAN_BE_HOST) || defined(__DOXYGEN__)\r
- /** Indicates the current host state machine state. When in host mode, this indicates the state\r
- * via one of the values of the \ref USB_Host_States_t enum values in Host.h.\r
- *\r
- * This value may be altered by the user application to implement the \ref HOST_STATE_Addressed,\r
- * \ref HOST_STATE_Configured, \ref HOST_STATE_Ready and \ref HOST_STATE_Suspended states which\r
- * are not implemented by the library.\r
- *\r
- * \note This global is only present if the user application can be a USB host.\r
- *\r
- * \ingroup Group_Host\r
- */\r
- extern volatile uint8_t USB_HostState;\r
+ #if defined(USB_CAN_BE_DEVICE) || defined(__DOXYGEN__)\r
+ #if !defined(DEVICE_STATE_AS_GPIOR) || defined(__DOXYGEN__)\r
+ /** Indicates the current device state machine state. When in device mode, this indicates the state\r
+ * via one of the values of the \ref USB_Device_States_t enum values.\r
+ *\r
+ * This value should not be altered by the user application as it is handled automatically by the\r
+ * library. The only exception to this rule is if the NO_LIMITED_CONTROLLER_CONNECT token is used\r
+ * (see \ref EVENT_USB_Device_Connect() and \ref EVENT_USB_Device_Disconnect() events).\r
+ *\r
+ * To reduce program size and speed up checks of this global, it can be placed into one of the AVR's\r
+ * GPIOR hardware registers instead of RAM by defining the DEVICE_STATE_AS_GPIOR token to a value \r
+ * between 0 and 2 in the project makefile and passing it to the compiler via the -D switch. When\r
+ * defined, the corresponding GPIOR register should not be used in the user application except\r
+ * implicitly via the library APIs.\r
+ *\r
+ * \note This global is only present if the user application can be a USB device.\r
+ *\r
+ * \note This variable should be treated as read-only in the user application, and never manually\r
+ * changed in value except in the circumstances outlined above.\r
+ *\r
+ * \see \ref USB_Device_States_t for a list of possible device states\r
+ *\r
+ * \ingroup Group_Device\r
+ */\r
+ extern volatile uint8_t USB_DeviceState;\r
+ #else\r
+ #define _GET_DEVICE_GPIOR_NAME2(y) GPIOR ## y\r
+ #define _GET_DEVICE_GPIOR_NAME(x) _GET_DEVICE_GPIOR_NAME2(x)\r
+ #define USB_DeviceState _GET_DEVICE_GPIOR_NAME(DEVICE_STATE_AS_GPIOR)\r
+ #endif\r