Add LUFA-111009-BETA tag.LUFA-111009-BETA

git-svn-id: http://lufa-lib.googlecode.com/svn/tags/LUFA-111009-BETA@1929 d5102386-fcda-11dd-9fdb-3debd5008f28

1 files changed, 298 insertions, 222 deletions

diff --git a/LUFA/Platform/XMEGA/ClockManagement.h b/LUFA/Platform/XMEGA/ClockManagement.h
index de531c29..dd8d60cc 100644
--- a/LUFA/Platform/XMEGA/ClockManagement.h
+++ b/LUFA/Platform/XMEGA/ClockManagement.h
@@ -1,222 +1,298 @@
-/*

-             LUFA Library

-     Copyright (C) Dean Camera, 2011.

-

-  dean [at] fourwalledcubicle [dot] com

-           www.lufa-lib.org

-*/

-

-/*

-  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)

-

-  Permission to use, copy, modify, distribute, and sell this

-  software and its documentation for any purpose is hereby granted

-  without fee, provided that the above copyright notice appear in

-  all copies and that both that the copyright notice and this

-  permission notice and warranty disclaimer appear in supporting

-  documentation, and that the name of the author not be used in

-  advertising or publicity pertaining to distribution of the

-  software without specific, written prior permission.

-

-  The author disclaim all warranties with regard to this

-  software, including all implied warranties of merchantability

-  and fitness.  In no event shall the author be liable for any

-  special, indirect or consequential damages or any damages

-  whatsoever resulting from loss of use, data or profits, whether

-  in an action of contract, negligence or other tortious action,

-  arising out of or in connection with the use or performance of

-  this software.

-*/

-

-/** \file

- *  \brief Module Clock Driver for the AVR USB XMEGA microcontrollers.

- *

- *  Clock management driver for the AVR USB XMEGA microcontrollers. This driver allows for the configuration

- *  of the various clocks within the device to clock the various peripherals.

- */

-

-/** \ingroup Group_PlatformDrivers

- *  \defgroup Group_PlatformDrivers_XMEGAClocks AVR USB XMEGA Clock Management Driver - LUFA/Platform/XMEGA/ClockManagement.h

- *  \brief Module Clock Driver for the AVR USB XMEGA microcontrollers.

- *

- *  \section Sec_Dependencies Module Source Dependencies

- *  The following files must be built with any user project that uses this module:

- *    - None

- *

- *  \section Sec_ModDescription Module Description

- *  Clock management driver for the AVR USB XMEGA microcontrollers. This driver allows for the configuration

- *  of the various clocks within the device to clock the various peripherals.

- *

- *  Usage Example:

- *  \code

- *		#include <LUFA/Platform/XMEGA/ClockManagement.h>

- *

- *		void main(void)

- *		{

- *			[TODO]

- *		}

- *  \endcode

- *

- *  @{

- */

-

-#ifndef _XMEGA_CLOCK_MANAGEMENT_H_

-#define _XMEGA_CLOCK_MANAGEMENT_H_

-

-	/* Includes: */

-		#include <LUFA/Common/Common.h>

-

-	/* Enable C linkage for C++ Compilers: */

-		#if defined(__cplusplus)

-			extern "C" {

-		#endif

-

-	/* Public Interface - May be used in end-application: */

-		/* Macros: */

-			/** Enum for the possible external oscillator types. */

-			enum XMEGA_Extern_OSC_ClockTypes_t

-			{

-				EXOSC_MODE_2MHZ_MAX      = OSC_FRQRANGE_04TO2_gc,  /**< External crystal oscillator equal to or slower than 2MHz. */

-				EXOSC_MODE_9MHZ_MAX      = OSC_FRQRANGE_2TO9_gc,   /**< External crystal oscillator equal to or slower than 9MHz. */

-				EXOSC_MODE_12MHZ_MAX     = OSC_FRQRANGE_9TO12_gc,  /**< External crystal oscillator equal to or slower than 12MHz. */

-				EXOSC_MODE_16MHZ_MAX     = OSC_FRQRANGE_12TO16_gc, /**< External crystal oscillator equal to or slower than 16MHz. */	

-			};

-

-			/** Enum for the possible external oscillator statup times. */

-			enum XMEGA_Extern_OSC_ClockStartup_t

-			{

-				EXOSC_START_6CLK         = OSC_XOSCSEL_EXTCLK_gc,      /**< Wait 6 clock cycles before startup (external clock). */

-				EXOSC_START_32KCLK       = OSC_XOSCSEL_32KHz_gc,       /**< Wait 32K clock cycles before startup (32.768KHz crystal). */

-				EXOSC_START_256CLK       = OSC_XOSCSEL_XTAL_256CLK_gc, /**< Wait 256 clock cycles before startup. */

-				EXOSC_START_1KCLK        = OSC_XOSCSEL_XTAL_1KCLK_gc,  /**< Wait 1K clock cycles before startup. */

-				EXOSC_START_16KCLK       = OSC_XOSCSEL_XTAL_16KCLK_gc, /**< Wait 16K clock cycles before startup. */

-			};

-			

-			/** Enum for the possible module clock sources. */

-			enum XMEGA_System_ClockSource_t

-			{

-				CLOCK_SRC_INT_RC2MHZ    = 0, /**< Clock sourced from the Internal 2MHz RC Oscillator clock. */

-				CLOCK_SRC_INT_RC32MHZ   = 1, /**< Clock sourced from the Internal 32MHz RC Oscillator clock. */

-				CLOCK_SRC_INT_RC32KHZ   = 2, /**< Clock sourced from the Internal 32KHz RC Oscillator clock. */

-				CLOCK_SRC_XOSC          = 3, /**< Clock sourced from the External Oscillator clock. */

-				CLOCK_SRC_PLL           = 4, /**< Clock sourced from the Internal PLL clock. */

-			};

-

-		/* Inline Functions: */

-			/** Starts the given external oscillator of the UC3 microcontroller, with the given options. This routine blocks until

-			 *  the oscillator is ready for use.

-			 *

-			 *  \param[in] Channel  Index of the external oscillator to start.

-			 *  \param[in] Type     Type of clock attached to the given oscillator channel, a value from \ref XMEGA_Extern_OSC_ClockTypes_t.

-			 *  \param[in] Startup  Statup time of the external oscillator, a value from \ref XMEGA_Extern_OSC_ClockStartup_t.

-			 *

-			 *  \return Boolean \c true if the external oscillator was successfully started, \c false if invalid parameters specified.

-			 */

-			static inline uint8_t AVR32CLK_StartExternalOscillator(const uint8_t Channel,

-			                                                       const uint8_t Type,

-			                                                       const uint8_t Startup) ATTR_ALWAYS_INLINE;

-			static inline uint8_t AVR32CLK_StartExternalOscillator(const uint8_t Channel,

-			                                                       const uint8_t Type,

-			                                                       const uint8_t Startup)

-			{

-				return false; // TODO

-			}

-

-			/** Stops the given external oscillator of the UC3 microcontroller.

-			 *

-			 *  \param[in] Channel  Index of the external oscillator to stop.

-			 */

-			static inline void AVR32CLK_StopExternalOscillator(const uint8_t Channel) ATTR_ALWAYS_INLINE;

-			static inline void AVR32CLK_StopExternalOscillator(const uint8_t Channel)

-			{

-				return; // TODO

-			}

-

-			/** Starts the given PLL of the UC3 microcontroller, with the given options. This routine blocks until the PLL is ready for use.

-			 *

-			 *  \param[in] Channel     Index of the PLL to start.

-			 *  \param[in] Source      Clock source for the PLL, a value from \ref XMEGA_System_ClockSource_t.

-			 *  \param[in] SourceFreq  Frequency of the PLL's clock source, in Hz.

-			 *  \param[in] Frequency   Target frequency of the PLL's output.

-			 *

-			 *  \return Boolean \c true if the PLL was successfully started, \c false if invalid parameters specified.

-			 */

-			static inline bool AVR32CLK_StartPLL(const uint8_t Channel,

-			                                     const uint8_t Source,

-			                                     const uint32_t SourceFreq,

-			                                     const uint32_t Frequency) ATTR_ALWAYS_INLINE;

-			static inline bool AVR32CLK_StartPLL(const uint8_t Channel,

-			                                     const uint8_t Source,

-			                                     const uint32_t SourceFreq,

-			                                     const uint32_t Frequency)

-			{

-				return false; // TODO

-			}

-

-			/** Stops the given PLL of the UC3 microcontroller.

-			 *

-			 *  \param[in] Channel  Index of the PLL to stop.

-			 */

-			static inline void AVR32CLK_StopPLL(const uint8_t Channel) ATTR_ALWAYS_INLINE;

-			static inline void AVR32CLK_StopPLL(const uint8_t Channel)

-			{

-				// TODO

-			}

-			

-			/** Starts the given Generic Clock of the UC3 microcontroller, with the given options.

-			 *

-			 *  \param[in] Channel     Index of the Generic Clock to start.

-			 *  \param[in] Source      Clock source for the Generic Clock, a value from \ref XMEGA_System_ClockSource_t.

-			 *  \param[in] SourceFreq  Frequency of the Generic Clock's clock source, in Hz.

-			 *  \param[in] Frequency   Target frequency of the Generic Clock's output.

-			 *

-			 *  \return Boolean \c true if the Generic Clock was successfully started, \c false if invalid parameters specified.

-			 */

-			static inline bool AVR32CLK_StartGenericClock(const uint8_t Channel,

-			                                              const uint8_t Source,

-			                                              const uint32_t SourceFreq,

-			                                              const uint32_t Frequency) ATTR_ALWAYS_INLINE;

-			static inline bool AVR32CLK_StartGenericClock(const uint8_t Channel,

-			                                              const uint8_t Source,

-			                                              const uint32_t SourceFreq,

-			                                              const uint32_t Frequency)

-			{

-				return false; // TODO

-			}

-			

-			/** Stops the given generic clock of the UC3 microcontroller.

-			 *

-			 *  \param[in] Channel  Index of the generic clock to stop.

-			 */

-			static inline void AVR32CLK_StopGenericClock(const uint8_t Channel) ATTR_ALWAYS_INLINE;

-			static inline void AVR32CLK_StopGenericClock(const uint8_t Channel)

-			{

-				// TODO

-			}

-			

-			/** Sets the clock source for the main microcontroller core. The given clock source should be configured

-			 *  and ready for use before this function is called.

-			 *

-			 *  This function will configure the FLASH controller's wait states automatically to suit the given clock source.

-			 *

-			 *  \param[in] Source      Clock source for the CPU core, a value from \ref XMEGA_System_ClockSource_t.

-			 *  \param[in] SourceFreq  Frequency of the CPU core's clock source, in Hz.

-			 *

-			 *  \return Boolean \c true if the CPU core clock was sucessfully altered, \c false if invalid parameters specified.

-			 */

-			static inline bool AVR32CLK_SetCPUClockSource(const uint8_t Source,

-			                                              const uint32_t SourceFreq) ATTR_ALWAYS_INLINE;

-			static inline bool AVR32CLK_SetCPUClockSource(const uint8_t Source,

-			                                              const uint32_t SourceFreq)

-			{

-				return false // TODO

-			}

-

-	/* Disable C linkage for C++ Compilers: */

-		#if defined(__cplusplus)

-			}

-		#endif

-

-#endif

-

-/** @} */

+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2011.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaim all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *  \brief Module Clock Driver for the AVR USB XMEGA microcontrollers.
+ *
+ *  Clock management driver for the AVR USB XMEGA microcontrollers. This driver allows for the configuration
+ *  of the various clocks within the device to clock the various peripherals.
+ */
+
+/** \ingroup Group_PlatformDrivers
+ *  \defgroup Group_PlatformDrivers_XMEGAClocks AVR USB XMEGA Clock Management Driver - LUFA/Platform/XMEGA/ClockManagement.h
+ *  \brief Module Clock Driver for the AVR USB XMEGA microcontrollers.
+ *
+ *  \section Sec_Dependencies Module Source Dependencies
+ *  The following files must be built with any user project that uses this module:
+ *    - None
+ *
+ *  \section Sec_ModDescription Module Description
+ *  Clock management driver for the AVR USB XMEGA microcontrollers. This driver allows for the configuration
+ *  of the various clocks within the device to clock the various peripherals.
+ *
+ *  Usage Example:
+ *  \code
+ *		#include <LUFA/Platform/XMEGA/ClockManagement.h>
+ *
+ *		void main(void)
+ *		{
+ *			// Start the internal 32MHz RC oscillator and switch the CPU core to run from it
+ *			AVR32CLK_StartInternalOscillator(CLOCK_SRC_INT_RC32MHZ);
+ *			XMEGACLK_SetCPUClockSource(CLOCK_SRC_INT_RC32MHZ, F_CPU);
+ *
+ *			// Start the external oscillator and multiply up the frequency
+ *			AVR32CLK_StartExternalOscillator(EXOSC_FREQ_9MHZ_MAX, EXOSC_START_1KCLK);
+ *			AVR32CLK_StartPLL(CLOCK_SRC_XOSC, 8000000, F_USB);
+ *		}
+ *  \endcode
+ *
+ *  @{
+ */
+
+#ifndef _XMEGA_CLOCK_MANAGEMENT_H_
+#define _XMEGA_CLOCK_MANAGEMENT_H_
+
+	/* Includes: */
+		#include <LUFA/Common/Common.h>
+
+	/* Enable C linkage for C++ Compilers: */
+		#if defined(__cplusplus)
+			extern "C" {
+		#endif
+
+	/* Public Interface - May be used in end-application: */
+		/* Macros: */
+			/** Enum for the possible external oscillator frequency ranges. */
+			enum XMEGA_Extern_OSC_ClockFrequency_t
+			{
+				EXOSC_FREQ_2MHZ_MAX      = OSC_FRQRANGE_04TO2_gc,  /**< External crystal oscillator equal to or slower than 2MHz. */
+				EXOSC_FREQ_9MHZ_MAX      = OSC_FRQRANGE_2TO9_gc,   /**< External crystal oscillator equal to or slower than 9MHz. */
+				EXOSC_FREQ_12MHZ_MAX     = OSC_FRQRANGE_9TO12_gc,  /**< External crystal oscillator equal to or slower than 12MHz. */
+				EXOSC_FREQ_16MHZ_MAX     = OSC_FRQRANGE_12TO16_gc, /**< External crystal oscillator equal to or slower than 16MHz. */	
+			};
+
+			/** Enum for the possible external oscillator statup times. */
+			enum XMEGA_Extern_OSC_ClockStartup_t
+			{
+				EXOSC_START_6CLK         = OSC_XOSCSEL_EXTCLK_gc,      /**< Wait 6 clock cycles before startup (external clock). */
+				EXOSC_START_32KCLK       = OSC_XOSCSEL_32KHz_gc,       /**< Wait 32K clock cycles before startup (32.768KHz crystal). */
+				EXOSC_START_256CLK       = OSC_XOSCSEL_XTAL_256CLK_gc, /**< Wait 256 clock cycles before startup. */
+				EXOSC_START_1KCLK        = OSC_XOSCSEL_XTAL_1KCLK_gc,  /**< Wait 1K clock cycles before startup. */
+				EXOSC_START_16KCLK       = OSC_XOSCSEL_XTAL_16KCLK_gc, /**< Wait 16K clock cycles before startup. */
+			};
+			
+			/** Enum for the possible module clock sources. */
+			enum XMEGA_System_ClockSource_t
+			{
+				CLOCK_SRC_INT_RC2MHZ    = 0, /**< Clock sourced from the Internal 2MHz RC Oscillator clock. */
+				CLOCK_SRC_INT_RC32MHZ   = 1, /**< Clock sourced from the Internal 32MHz RC Oscillator clock. */
+				CLOCK_SRC_INT_RC32KHZ   = 2, /**< Clock sourced from the Internal 32KHz RC Oscillator clock. */
+				CLOCK_SRC_XOSC          = 3, /**< Clock sourced from the External Oscillator clock. */
+				CLOCK_SRC_PLL           = 4, /**< Clock sourced from the Internal PLL clock. */
+			};
+
+		/* Inline Functions: */
+			/** Starts the external oscillator of the XMEGA microcontroller, with the given options. This routine blocks until
+			 *  the oscillator is ready for use.
+			 *
+			 *  \param[in] FreqRange  Frequency range of the external oscillator, a value from \ref XMEGA_Extern_OSC_ClockFrequency_t.
+			 *  \param[in] Startup    Statup time of the external oscillator, a value from \ref XMEGA_Extern_OSC_ClockStartup_t.
+			 *
+			 *  \return Boolean \c true if the external oscillator was successfully started, \c false if invalid parameters specified.
+			 */
+			static inline bool XMEGACLK_StartExternalOscillator(const uint8_t FreqRange,
+			                                                    const uint8_t Startup) ATTR_ALWAYS_INLINE;
+			static inline bool XMEGACLK_StartExternalOscillator(const uint8_t FreqRange,
+			                                                    const uint8_t Startup)
+			{
+				OSC.XOSCCTRL  = (FreqRange | ((Startup == EXOSC_START_32KCLK) ? OSC_X32KLPM_bm : 0) | Startup);
+				OSC.CTRL     |= OSC_XOSCEN_bm;
+				
+				while (!(OSC.STATUS & OSC_XOSCRDY_bm));				
+				return true;
+			}
+
+			/** Stops the external oscillator of the XMEGA microcontroller. */
+			static inline void XMEGACLK_StopExternalOscillator(void) ATTR_ALWAYS_INLINE;
+			static inline void XMEGACLK_StopExternalOscillator(void)
+			{
+				OSC.CTRL     &= ~OSC_XOSCEN_bm;
+			}
+
+			/** Starts the given internal oscillator of the XMEGA microcontroller, with the given options. This routine blocks until
+			 *  the oscillator is ready for use.
+			 *
+			 *  \param[in] Source  Internal oscillator to start, a value from \ref XMEGA_System_ClockSource_t.
+			 *
+			 *  \return Boolean \c true if the internal oscillator was successfully started, \c false if invalid parameters specified.
+			 */
+			static inline uint8_t XMEGACLK_StartInternalOscillator(const uint8_t Source) ATTR_ALWAYS_INLINE;
+			static inline uint8_t XMEGACLK_StartInternalOscillator(const uint8_t Source)
+			{
+				switch (Source)
+				{
+					case CLOCK_SRC_INT_RC2MHZ:
+						OSC.CTRL |= OSC_RC2MEN_bm;
+						while (!(OSC.STATUS & OSC_RC2MRDY_bm));
+						return true;
+					case CLOCK_SRC_INT_RC32MHZ:
+						OSC.CTRL |= OSC_RC32MEN_bm;
+						while (!(OSC.STATUS & OSC_RC32MRDY_bm));					
+						return true;
+					case CLOCK_SRC_INT_RC32KHZ:
+						OSC.CTRL |= OSC_RC32KEN_bm;
+						while (!(OSC.STATUS & OSC_RC32KRDY_bm));					
+						return true;
+				}
+			
+				return false;
+			}
+
+			/** Stops the given internal oscillator of the XMEGA microcontroller.
+			 *
+			 *  \param[in] Source  Internal oscillator to stop, a value from \ref XMEGA_System_ClockSource_t.
+			 *
+			 *  \return Boolean \c true if the internal oscillator was successfully stopped, \c false if invalid parameters specified.
+			 */			
+			static inline bool XMEGACLK_StopInternalOscillator(const uint8_t Source) ATTR_ALWAYS_INLINE;
+			static inline bool XMEGACLK_StopInternalOscillator(const uint8_t Source)
+			{
+				switch (Source)
+				{
+					case CLOCK_SRC_INT_RC2MHZ:
+						OSC.CTRL &= ~OSC_RC2MEN_bm;
+						return true;
+					case CLOCK_SRC_INT_RC32MHZ:
+						OSC.CTRL &= ~OSC_RC32MEN_bm;
+						return true;
+					case CLOCK_SRC_INT_RC32KHZ:
+						OSC.CTRL &= ~OSC_RC32KEN_bm;
+						return true;
+				}
+			
+				return false;
+			}
+
+			/** Starts the PLL of the XMEGA microcontroller, with the given options. This routine blocks until the PLL is ready for use.
+			 *
+			 *  \note The output frequency must be equal to or greater than the source frequency.
+			 *
+			 *  \param[in] Source       Clock source for the PLL, a value from \ref XMEGA_System_ClockSource_t.
+			 *  \param[in] SourceFreq   Frequency of the PLL's clock source, in Hz.
+			 *  \param[in] Frequency    Target frequency of the PLL's output.
+			 *
+			 *  \return Boolean \c true if the PLL was successfully started, \c false if invalid parameters specified.
+			 */
+			static inline bool XMEGACLK_StartPLL(const uint8_t Source,
+			                                     const uint32_t SourceFreq,
+			                                     const uint32_t Frequency) ATTR_ALWAYS_INLINE;
+			static inline bool XMEGACLK_StartPLL(const uint8_t Source,
+			                                     const uint32_t SourceFreq,
+			                                     const uint32_t Frequency)
+			{
+				uint8_t MulFactor = (Frequency / SourceFreq);
+				
+				if (SourceFreq > Frequency)
+				  return false;				
+			
+				switch (Source)
+				{
+					case CLOCK_SRC_INT_RC2MHZ:
+						OSC.PLLCTRL = (OSC_PLLSRC_RC2M_gc  | MulFactor);
+						break;
+					case CLOCK_SRC_INT_RC32MHZ:
+						OSC.PLLCTRL = (OSC_PLLSRC_RC32M_gc | MulFactor);
+						break;
+					case CLOCK_SRC_XOSC:
+						OSC.PLLCTRL = (OSC_PLLSRC_XOSC_gc  | MulFactor);
+						break;
+					default:
+						return false;
+				}
+
+				OSC.CTRL |= OSC_PLLEN_bm;
+				
+				while (!(OSC.STATUS & OSC_PLLRDY_bm));
+				return true;
+			}
+
+			/** Stops the PLL of the XMEGA microcontroller. */
+			static inline void XMEGACLK_StopPLL(void) ATTR_ALWAYS_INLINE;
+			static inline void XMEGACLK_StopPLL(void)
+			{
+				OSC.CTRL &= ~OSC_PLLEN_bm;
+			}
+			
+			/** Sets the clock source for the main microcontroller core. The given clock source should be configured
+			 *  and ready for use before this function is called.
+			 *
+			 *  \param[in] Source      Clock source for the CPU core, a value from \ref XMEGA_System_ClockSource_t.
+			 *  \param[in] SourceFreq  Frequency of the CPU core's clock source, in Hz.
+			 *
+			 *  \return Boolean \c true if the CPU core clock was sucessfully altered, \c false if invalid parameters specified.
+			 */
+			static inline bool XMEGACLK_SetCPUClockSource(const uint8_t Source,
+			                                              const uint32_t SourceFreq) ATTR_ALWAYS_INLINE;
+			static inline bool XMEGACLK_SetCPUClockSource(const uint8_t Source,
+			                                              const uint32_t SourceFreq)
+			{
+				uint8_t ClockSourceMask = 0;
+			
+				switch (Source)
+				{
+					case CLOCK_SRC_INT_RC2MHZ:
+						ClockSourceMask = CLK_SCLKSEL_RC2M_gc;
+						break;
+					case CLOCK_SRC_INT_RC32MHZ:
+						ClockSourceMask = CLK_SCLKSEL_RC32M_gc;
+						break;
+					case CLOCK_SRC_INT_RC32KHZ:
+						ClockSourceMask = CLK_SCLKSEL_RC32K_gc;
+						break;
+					case CLOCK_SRC_XOSC:
+						ClockSourceMask = CLK_SCLKSEL_XOSC_gc;
+						break;
+					case CLOCK_SRC_PLL:
+						ClockSourceMask = CLK_SCLKSEL_PLL_gc;
+						break;
+					default:
+						return false;
+				}
+				
+				uint_reg_t CurrentGlobalInt = GetGlobalInterruptMask();
+				GlobalInterruptDisable();
+
+				CCP      = CCP_IOREG_gc;
+				CLK.CTRL = ClockSourceMask;
+				
+				SetGlobalInterruptMask(CurrentGlobalInt);
+				
+				Delay_MS(1);				
+				return (CLK.CTRL == ClockSourceMask);
+			}
+
+	/* Disable C linkage for C++ Compilers: */
+		#if defined(__cplusplus)
+			}
+		#endif
+
+#endif
+
+/** @} */