clkout.c

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/*
 * @brief CLKOUT example
 *
 * @note
 * Copyright(C) NXP Semiconductors, 2012
 * All rights reserved.
 *
 * @par
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * LPC products.  This software is supplied "AS IS" without any warranties of
 * any kind, and NXP Semiconductors and its licensor disclaim any and
 * all warranties, express or implied, including all implied warranties of
 * merchantability, fitness for a particular purpose and non-infringement of
 * intellectual property rights.  NXP Semiconductors assumes no responsibility
 * or liability for the use of the software, conveys no license or rights under any
 * patent, copyright, mask work right, or any other intellectual property rights in
 * or to any products. NXP Semiconductors reserves the right to make changes
 * in the software without notification. NXP Semiconductors also makes no
 * representation or warranty that such application will be suitable for the
 * specified use without further testing or modification.
 *
 * @par
 * Permission to use, copy, modify, and distribute this software and its
 * documentation is hereby granted, under NXP Semiconductors' and its
 * licensor's relevant copyrights in the software, without fee, provided that it
 * is used in conjunction with NXP Semiconductors microcontrollers.  This
 * copyright, permission, and disclaimer notice must appear in all copies of
 * this code.
 */

#include "board.h"
#include <stdio.h>

/*****************************************************************************
 * Private types/enumerations/variables
 ****************************************************************************/

static volatile uint32_t ticks100;

/*****************************************************************************
 * Public types/enumerations/variables
 ****************************************************************************/

/*****************************************************************************
 * Private functions
 ****************************************************************************/

/*****************************************************************************
 * Public functions
 ****************************************************************************/

void SysTick_Handler(void)
{
 ticks100++;
 if ((ticks100 % 100) == 0) {
  Board_LED_Toggle(0);
 }
}

int main(void)
{
 CHIP_SYSCTL_CLKOUTSRC_T clkoutClks;

 Board_Init();

 /* Enable the power to the WDT */
 Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_WDTOSC_PD);

 /*This example uses the watchdog oscillator set at a 50KHz (1Mhz / 20) clock rate. */
 Chip_Clock_SetWDTOSC(WDTLFO_OSC_1_05, 20);
 
 /* Enable and setup SysTick Timer at a 100Hz rate */
 SysTick_Config(SystemCoreClock / 100);

 /* Cycle through all clock sources for the CLKOUT pin */
 for (clkoutClks = SYSCTL_CLKOUTSRC_IRC;
   clkoutClks <= SYSCTL_CLKOUTSRC_MAINSYSCLK; clkoutClks++) {
  ticks100 = 0;

  /* Setup CLKOUT pin for specific clock with a divider of 1 */
  Chip_Clock_SetCLKOUTSource(clkoutClks, 1);

  /* Wait 5 seconds */
  while (ticks100 < 500) {
   __WFI();
  }
 }

 /* Disable CLKOUT pin by setting divider to 0 */
 Chip_Clock_SetCLKOUTSource(SYSCTL_CLKOUTSRC_IRC, 0);

 return 0;
}