- /** Event for unhandled control requests. This event fires when a the USB host issues a control
- * request to the control endpoint (address 0) that the library does not handle. This may either
- * be a standard request that the library has no handler code for, or a class specific request
- * issued to the device which must be handled appropriately.
+ /** Event for control requests. This event fires when a the USB host issues a control request
+ * to the mandatory device control endpoint (of address 0). This may either be a standard
+ * request that the library may have a handler code for internally, or a class specific request
+ * issued to the device which must be handled appropriately. If a request is not processed in the
+ * user application via this event, it will be passed to the library for processing internally
+ * if a suitable handler exists.