rtc.c

Go to the documentation of this file.

/*
 * @brief RTC 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"

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

static volatile bool fIntervalReached;
static volatile bool fAlarmTimeMatched;
static volatile bool On0, On1;

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

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

/* Gets and shows the current time and date */
static void showTime(IP_RTC_TIME_T *pTime)
{
 DEBUGOUT("Time: %.2d:%.2d:%.2d %.2d/%.2d/%.4d\r\n", pTime->time[RTC_TIMETYPE_HOUR],
    pTime->time[RTC_TIMETYPE_MINUTE],
    pTime->time[RTC_TIMETYPE_SECOND],
    pTime->time[RTC_TIMETYPE_MONTH],
    pTime->time[RTC_TIMETYPE_DAYOFMONTH],
    pTime->time[RTC_TIMETYPE_YEAR]);
}

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

void RTC_IRQHandler(void)
{
 uint32_t sec;

 /* Toggle heart beat LED for each second field change interrupt */
 if (Chip_RTC_GetIntPending(LPC_RTC, RTC_INT_COUNTER_INCREASE)) {
  /* Clear pending interrupt */
  Chip_RTC_ClearIntPending(LPC_RTC, RTC_INT_COUNTER_INCREASE);
  On0 = (bool) !On0;
  Board_LED_Set(0, On0);
 }

 /* display timestamp every 5 seconds in the background */
 sec = Chip_RTC_GetTime(LPC_RTC, RTC_TIMETYPE_SECOND);
 if (!(sec % 5)) {
  fIntervalReached = true; /* set flag for background */
 }

 /* Check for alarm match */
 if (Chip_RTC_GetIntPending(LPC_RTC, RTC_INT_ALARM)) {
  /* Clear pending interrupt */
  Chip_RTC_ClearIntPending(LPC_RTC, RTC_INT_ALARM);
  fAlarmTimeMatched = true; /* set alarm handler flag */
 }
}

int main(void)
{
 IP_RTC_TIME_T FullTime;

 Board_Init();

 fIntervalReached  = 0;
 fAlarmTimeMatched = 0;
 On0 = On1 = false;
 Board_LED_Set(2, false);

 DEBUGSTR("The RTC operates on a 1 Hz clock.\r\n" \
    "Register writes can take up to 2 cycles.\r\n" \
    "It will take a few seconds to fully\r\n" \
    "initialize it and start it running.\r\n\r\n");

 DEBUGSTR("We'll print a timestamp every 5 seconds.\r\n" \
    "...and another when the alarm occurs.\r\n");

 Chip_RTC_Init(LPC_RTC);

 /* Set current time for RTC 2:00:00PM, 2012-10-05 */
 FullTime.time[RTC_TIMETYPE_SECOND]  = 0;
 FullTime.time[RTC_TIMETYPE_MINUTE]  = 0;
 FullTime.time[RTC_TIMETYPE_HOUR]    = 14;
 FullTime.time[RTC_TIMETYPE_DAYOFMONTH]  = 5;
 FullTime.time[RTC_TIMETYPE_DAYOFWEEK]   = 5;
 FullTime.time[RTC_TIMETYPE_DAYOFYEAR]   = 279;
 FullTime.time[RTC_TIMETYPE_MONTH]   = 10;
 FullTime.time[RTC_TIMETYPE_YEAR]    = 2012;

 Chip_RTC_SetFullTime(LPC_RTC, &FullTime);

 /* Set ALARM time for 17 seconds from time */
 FullTime.time[RTC_TIMETYPE_SECOND]  = 17;
 Chip_RTC_SetFullAlarmTime(LPC_RTC, &FullTime);

 /* Set the RTC to generate an interrupt on each second */
 Chip_RTC_CntIncrIntConfig(LPC_RTC, RTC_AMR_CIIR_IMSEC, ENABLE);

 /* Enable matching for alarm for second, minute, hour fields only */
 Chip_RTC_AlarmIntConfig(LPC_RTC, RTC_AMR_CIIR_IMSEC | RTC_AMR_CIIR_IMMIN | RTC_AMR_CIIR_IMHOUR, ENABLE);

 /* Clear interrupt pending */
 Chip_RTC_ClearIntPending(LPC_RTC, RTC_INT_COUNTER_INCREASE | RTC_INT_ALARM);

 /* Enable RTC interrupt in NVIC */
 NVIC_EnableIRQ((IRQn_Type) RTC_IRQn);

 /* Enable RTC (starts increase the tick counter and second counter register) */
 Chip_RTC_Enable(LPC_RTC, ENABLE);

 /* Loop forever */
 while (1) {
  if (fIntervalReached) { /* Every 5s */
   fIntervalReached = 0;

   On1 = (bool) !On1;
   Board_LED_Set(1, On1);

   /* read and display time */
   Chip_RTC_GetFullTime(LPC_RTC, &FullTime);
   showTime(&FullTime);
  }

  if (fAlarmTimeMatched) {
   fAlarmTimeMatched = false;

   /* announce event */
   DEBUGSTR("ALARM triggered!\r\n");
   Board_LED_Set(2, true);

   /* read and display time */
   Chip_RTC_GetFullTime(LPC_RTC, &FullTime);
   showTime(&FullTime);
  }
 }
}