tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/rtc_api.c

   1 /* mbed Microcontroller Library
   2  *******************************************************************************
   3  * Copyright (c) 2014, STMicroelectronics
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright notice,
  10  *    this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright notice,
  12  *    this list of conditions and the following disclaimer in the documentation
  13  *    and/or other materials provided with the distribution.
  14  * 3. Neither the name of STMicroelectronics nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  25  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *******************************************************************************
  29  */
  30 #include "rtc_api.h"
  31
  32 #if DEVICE_RTC
  33
  34 #include "mbed_error.h"
  35
  36 static int rtc_inited = 0;
  37
  38 static RTC_HandleTypeDef RtcHandle;
  39
  40 void rtc_init(void)
  41 {
  42     RCC_OscInitTypeDef RCC_OscInitStruct;
  43     uint32_t rtc_freq = 0;
  44
  45     if (rtc_inited) return;
  46     rtc_inited = 1;
  47
  48     RtcHandle.Instance = RTC;
  49
  50     // Enable Power clock
  51     __PWR_CLK_ENABLE();
  52
  53     // Enable access to Backup domain
  54     HAL_PWR_EnableBkUpAccess();
  55
  56     // Reset Backup domain
  57     __HAL_RCC_BACKUPRESET_FORCE();
  58     __HAL_RCC_BACKUPRESET_RELEASE();
  59
  60     // Enable LSE Oscillator
  61     RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
  62     RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; /* Mandatory, otherwise the PLL is reconfigured! */
  63     RCC_OscInitStruct.LSEState       = RCC_LSE_ON; /* External 32.768 kHz clock on OSC_IN/OSC_OUT */
  64     if (HAL_RCC_OscConfig(&RCC_OscInitStruct) == HAL_OK) {
  65         // Connect LSE to RTC
  66         __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSE);
  67         __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSE);
  68         rtc_freq = LSE_VALUE;
  69     } else {
  70         // Enable LSI clock
  71         RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
  72         RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; // Mandatory, otherwise the PLL is reconfigured!
  73         RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
  74         RCC_OscInitStruct.LSIState       = RCC_LSI_ON;
  75         if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
  76             error("RTC error: LSI clock initialization failed.");
  77         }
  78         // Connect LSI to RTC
  79         __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSI);
  80         __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSI);
  81         // [TODO] This value is LSI typical value. To be measured precisely using a timer input capture
  82         rtc_freq = LSI_VALUE;
  83     }
  84
  85     // Enable RTC
  86     __HAL_RCC_RTC_ENABLE();
  87
  88     RtcHandle.Init.HourFormat     = RTC_HOURFORMAT_24;
  89     RtcHandle.Init.AsynchPrediv   = 127;
  90     RtcHandle.Init.SynchPrediv    = (rtc_freq / 128) - 1;
  91     RtcHandle.Init.OutPut         = RTC_OUTPUT_DISABLE;
  92     RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
  93     RtcHandle.Init.OutPutType     = RTC_OUTPUT_TYPE_OPENDRAIN;
  94
  95     if (HAL_RTC_Init(&RtcHandle) != HAL_OK) {
  96         error("RTC error: RTC initialization failed.");
  97     }
  98 }
  99
 100 void rtc_free(void)
 101 {
 102     // Enable Power clock
 103     __PWR_CLK_ENABLE();
 104
 105     // Enable access to Backup domain
 106     HAL_PWR_EnableBkUpAccess();
 107
 108     // Reset Backup domain
 109     __HAL_RCC_BACKUPRESET_FORCE();
 110     __HAL_RCC_BACKUPRESET_RELEASE();
 111
 112     // Disable access to Backup domain
 113     HAL_PWR_DisableBkUpAccess();
 114
 115     // Disable LSI and LSE clocks
 116     RCC_OscInitTypeDef RCC_OscInitStruct;
 117     RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
 118     RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE;
 119     RCC_OscInitStruct.LSIState       = RCC_LSI_OFF;
 120     RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
 121     HAL_RCC_OscConfig(&RCC_OscInitStruct);
 122
 123     rtc_inited = 0;
 124 }
 125
 126 int rtc_isenabled(void)
 127 {
 128     return rtc_inited;
 129 }
 130
 131 /*
 132  RTC Registers
 133    RTC_WeekDay 1=monday, 2=tuesday, ..., 7=sunday
 134    RTC_Month   1=january, 2=february, ..., 12=december
 135    RTC_Date    day of the month 1-31
 136    RTC_Year    year 0-99
 137  struct tm
 138    tm_sec      seconds after the minute 0-61
 139    tm_min      minutes after the hour 0-59
 140    tm_hour     hours since midnight 0-23
 141    tm_mday     day of the month 1-31
 142    tm_mon      months since January 0-11
 143    tm_year     years since 1900
 144    tm_wday     days since Sunday 0-6
 145    tm_yday     days since January 1 0-365
 146    tm_isdst    Daylight Saving Time flag
 147 */
 148 time_t rtc_read(void)
 149 {
 150     RTC_DateTypeDef dateStruct;
 151     RTC_TimeTypeDef timeStruct;
 152     struct tm timeinfo;
 153
 154     RtcHandle.Instance = RTC;
 155
 156     // Read actual date and time
 157     // Warning: the time must be read first!
 158     HAL_RTC_GetTime(&RtcHandle, &timeStruct, FORMAT_BIN);
 159     HAL_RTC_GetDate(&RtcHandle, &dateStruct, FORMAT_BIN);
 160
 161     // Setup a tm structure based on the RTC
 162     timeinfo.tm_wday = dateStruct.WeekDay;
 163     timeinfo.tm_mon  = dateStruct.Month - 1;
 164     timeinfo.tm_mday = dateStruct.Date;
 165     timeinfo.tm_year = dateStruct.Year + 100;
 166     timeinfo.tm_hour = timeStruct.Hours;
 167     timeinfo.tm_min  = timeStruct.Minutes;
 168     timeinfo.tm_sec  = timeStruct.Seconds;
 169
 170     // Convert to timestamp
 171     time_t t = mktime(&timeinfo);
 172
 173     return t;
 174 }
 175
 176 void rtc_write(time_t t)
 177 {
 178     RTC_DateTypeDef dateStruct;
 179     RTC_TimeTypeDef timeStruct;
 180
 181     RtcHandle.Instance = RTC;
 182
 183     // Convert the time into a tm
 184     struct tm *timeinfo = localtime(&t);
 185
 186     // Fill RTC structures
 187     dateStruct.WeekDay        = timeinfo->tm_wday;
 188     dateStruct.Month          = timeinfo->tm_mon + 1;
 189     dateStruct.Date           = timeinfo->tm_mday;
 190     dateStruct.Year           = timeinfo->tm_year - 100;
 191     timeStruct.Hours          = timeinfo->tm_hour;
 192     timeStruct.Minutes        = timeinfo->tm_min;
 193     timeStruct.Seconds        = timeinfo->tm_sec;
 194     timeStruct.TimeFormat     = RTC_HOURFORMAT12_PM;
 195     timeStruct.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
 196     timeStruct.StoreOperation = RTC_STOREOPERATION_RESET;
 197
 198     // Change the RTC current date/time
 199     HAL_RTC_SetDate(&RtcHandle, &dateStruct, FORMAT_BIN);
 200     HAL_RTC_SetTime(&RtcHandle, &timeStruct, FORMAT_BIN);
 201 }
 202
 203 #endif