source: rtos_arduino/trunk/arduino_lib/hardware/tools/CMSIS/Device/ATMEL/samd21/source/system_samd21.c@ 136

/**
 * \file
 *
 * \brief Low-level initialization functions called upon chip startup.
 *
 * Copyright (c) 2014 Atmel Corporation. All rights reserved.
 *
 * \asf_license_start
 *
 * \page License
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * 3. The name of Atmel may not be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * 4. This software may only be redistributed and used in connection with an
 *    Atmel microcontroller product.
 *
 * 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
 * EXPRESSLY AND SPECIFICALLY 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.
 *
 * \asf_license_stop
 *
 */

#include "samd21.h"

/**
 * Initial system clock frequency. The System RC Oscillator (RCSYS) provides
 *  the source for the main clock at chip startup.
 */
#define __SYSTEM_CLOCK    (1000000)

uint32_t SystemCoreClock = __SYSTEM_CLOCK;/*!< System Clock Frequency (Core Clock)*/

/**
 * Initialize the system
 *
 * @brief  Setup the microcontroller system.
 *         Initialize the System and update the SystemCoreClock variable.
 */
void SystemInit(void)
{
        // Keep the default device state after reset
        SystemCoreClock = __SYSTEM_CLOCK;
        return;
}

/**
 * Update SystemCoreClock variable
 *
 * @brief  Updates the SystemCoreClock with current core Clock
 *         retrieved from cpu registers.
 */
void SystemCoreClockUpdate(void)
{
        // Not implemented
        SystemCoreClock = __SYSTEM_CLOCK;
        return;
}