diff --git a/sam3s_example/sam3s_examples_include/async.h b/sam3s_example/sam3s_examples_include/async.h
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+/* ----------------------------------------------------------------------------
+ *         ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2009, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+/**
+ * \file
+ *
+ * Provide a routine for asynchronous transfer.
+ *
+ */
+
+#ifndef _ASYNC_
+#define _ASYNC_
+
+
+/*----------------------------------------------------------------------------
+ *        Headers
+ *----------------------------------------------------------------------------*/
+#include <stdint.h>
+
+/*----------------------------------------------------------------------------
+ *        Definition
+ *----------------------------------------------------------------------------*/
+/** Transfer is still pending.*/
+#define ASYNC_STATUS_PENDING        0xFF
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/*----------------------------------------------------------------------------
+ *        Type
+ *----------------------------------------------------------------------------*/
+/** \brief Asynchronous transfer descriptor. */
+typedef struct _Async
+{
+    /** Asynchronous transfer status.*/
+    volatile uint8_t status ;
+    /** Callback function to invoke when transfer completes or fails.*/
+    void *callback ;
+    /** Driver storage area; do not use.*/
+    uint32_t pStorage[4] ;
+} Async ;
+
+/*----------------------------------------------------------------------------
+ *        Global functions
+ *----------------------------------------------------------------------------*/
+extern uint32_t ASYNC_IsFinished( Async* pAsync ) ;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* #ifndef _ASYNC_ */
+