diff --git a/libraries/AP_Common/AP_Common.cpp b/libraries/AP_Common/AP_Common.cpp
new file mode 100644
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+++ b/libraries/AP_Common/AP_Common.cpp
@@ -0,0 +1,17 @@
+// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: t -*-
+//
+// This is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License as published by the
+// Free Software Foundation; either version 2.1 of the License, or (at
+// your option) any later version.
+//
+
+/// @file		AP_Common.cpp
+/// @brief		Common utility routines for the ArduPilot libraries.
+///
+/// @note		Exercise restraint adding code here; everything in this
+///				library will be linked with any sketch using it.
+///
+
+#include "AP_Common.h"
+
diff --git a/libraries/AP_Common/AP_Common.h b/libraries/AP_Common/AP_Common.h
new file mode 100644
index 0000000000..a6a6480f39
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+++ b/libraries/AP_Common/AP_Common.h
@@ -0,0 +1,56 @@
+// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: t -*-
+//
+// This is free software; you can redistribute it and/or modify it under
+// the terms of the GNU Lesser General Public License as published by the
+// Free Software Foundation; either version 2.1 of the License, or (at
+// your option) any later version.
+//
+
+#ifndef _AP_COMMON_H
+#define _AP_COMMON_H
+
+///
+/// @file 		AP_Common.h
+/// @brief		Common definitions and utility routines for the ArduPilot
+///				libraries.
+///
+/// @note		For correct operation, all sketches and libraries should
+///				include this header *before* any other.  In
+///				particular, this is critical for things like the
+///				FastSerial library, which need the opportunity to
+///				override parts of the Arduino infrastructure.
+///
+
+
+////////////////////////////////////////////////////////////////////////////////
+/// @name	Types
+///
+/// Data structures and types used throughout the libraries and applications.
+///
+//@{
+
+struct Location {
+	uint8_t		id;					///< command id
+	uint8_t		p1;					///< param 1
+	int32_t		alt;				///< param 2 - Altitude in centimeters (meters * 100)
+	int32_t		lat;				///< param 3 - Lattitude * 10**7
+	int32_t		lng;				///< param 4 - Longitude * 10**7
+};
+
+//@}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @name	Conversions
+///
+/// Conversion macros and factors.
+///
+//@{
+
+/// XXX this should probably be replaced with radians()/degrees(), but their
+/// inclusion in wiring.h makes doing that here difficult.
+#define ToDeg(x) (x*57.2957795131)	// *180/pi
+
+//@}
+
+
+#endif // _AP_COMMON_H