Ken Todotani / mbed-src

mbed library sources

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targets/hal/TARGET_STM/TARGET_NUCLEO_F302R8/rtc_api.c@170:bfbcaf535cca, 2014-04-24 (annotated)

Committer:
mbed_official
Date:
Thu Apr 24 15:30:06 2014 +0100
Revision:
170:bfbcaf535cca
Parent:
162:937d965048d3
Child:
216:577900467c9e
Synchronized with git revision 99a8b2179e9ca41d7254f71e1e46202718aa663d



Full URL: https://github.com/mbedmicro/mbed/commit/99a8b2179e9ca41d7254f71e1e46202718aa663d/



[NUCLEO_F302R8] Add LSE configuration for RTC

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 125:23cc3068a9e4 1 /* mbed Microcontroller Library
mbed_official 125:23cc3068a9e4 2 *******************************************************************************
mbed_official 125:23cc3068a9e4 3 * Copyright (c) 2014, STMicroelectronics
mbed_official 125:23cc3068a9e4 4 * All rights reserved.
mbed_official 125:23cc3068a9e4 5 *
mbed_official 125:23cc3068a9e4 6 * Redistribution and use in source and binary forms, with or without
mbed_official 125:23cc3068a9e4 7 * modification, are permitted provided that the following conditions are met:
mbed_official 125:23cc3068a9e4 8 *
mbed_official 125:23cc3068a9e4 9 * 1. Redistributions of source code must retain the above copyright notice,
mbed_official 125:23cc3068a9e4 10 * this list of conditions and the following disclaimer.
mbed_official 125:23cc3068a9e4 11 * 2. Redistributions in binary form must reproduce the above copyright notice,
mbed_official 125:23cc3068a9e4 12 * this list of conditions and the following disclaimer in the documentation
mbed_official 125:23cc3068a9e4 13 * and/or other materials provided with the distribution.
mbed_official 125:23cc3068a9e4 14 * 3. Neither the name of STMicroelectronics nor the names of its contributors
mbed_official 125:23cc3068a9e4 15 * may be used to endorse or promote products derived from this software
mbed_official 125:23cc3068a9e4 16 * without specific prior written permission.
mbed_official 125:23cc3068a9e4 17 *
mbed_official 125:23cc3068a9e4 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
mbed_official 125:23cc3068a9e4 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
mbed_official 125:23cc3068a9e4 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
mbed_official 125:23cc3068a9e4 21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
mbed_official 125:23cc3068a9e4 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
mbed_official 125:23cc3068a9e4 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
mbed_official 125:23cc3068a9e4 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
mbed_official 125:23cc3068a9e4 25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
mbed_official 125:23cc3068a9e4 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
mbed_official 125:23cc3068a9e4 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
mbed_official 125:23cc3068a9e4 28 *******************************************************************************
mbed_official 125:23cc3068a9e4 29 */
mbed_official 125:23cc3068a9e4 30 #include "rtc_api.h"
mbed_official 125:23cc3068a9e4 31
mbed_official 162:937d965048d3 32 #if DEVICE_RTC
mbed_official 162:937d965048d3 33
mbed_official 170:bfbcaf535cca 34 #include "wait_api.h"
mbed_official 170:bfbcaf535cca 35
mbed_official 170:bfbcaf535cca 36 #define LSE_STARTUP_TIMEOUT ((uint16_t)500) // delay in ms
mbed_official 170:bfbcaf535cca 37
mbed_official 125:23cc3068a9e4 38 static int rtc_inited = 0;
mbed_official 125:23cc3068a9e4 39
mbed_official 125:23cc3068a9e4 40 void rtc_init(void) {
mbed_official 170:bfbcaf535cca 41 uint32_t StartUpCounter = 0;
mbed_official 170:bfbcaf535cca 42 uint32_t LSEStatus = 0;
mbed_official 170:bfbcaf535cca 43 uint32_t rtc_freq = 0;
mbed_official 170:bfbcaf535cca 44
mbed_official 125:23cc3068a9e4 45 RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE); // Enable PWR clock
mbed_official 125:23cc3068a9e4 46
mbed_official 170:bfbcaf535cca 47 PWR_BackupAccessCmd(ENABLE); // Enable access to Backup domain
mbed_official 125:23cc3068a9e4 48
mbed_official 170:bfbcaf535cca 49 // Reset back up registers
mbed_official 125:23cc3068a9e4 50 RCC_BackupResetCmd(ENABLE);
mbed_official 125:23cc3068a9e4 51 RCC_BackupResetCmd(DISABLE);
mbed_official 170:bfbcaf535cca 52
mbed_official 170:bfbcaf535cca 53 // Enable LSE clock
mbed_official 170:bfbcaf535cca 54 RCC_LSEConfig(RCC_LSE_ON);
mbed_official 135:067cc8ba23da 55
mbed_official 170:bfbcaf535cca 56 // Wait till LSE is ready
mbed_official 170:bfbcaf535cca 57 do {
mbed_official 170:bfbcaf535cca 58 LSEStatus = RCC_GetFlagStatus(RCC_FLAG_LSERDY);
mbed_official 170:bfbcaf535cca 59 wait_ms(1);
mbed_official 170:bfbcaf535cca 60 StartUpCounter++;
mbed_official 170:bfbcaf535cca 61 } while((LSEStatus == 0) && (StartUpCounter <= LSE_STARTUP_TIMEOUT));
mbed_official 135:067cc8ba23da 62
mbed_official 170:bfbcaf535cca 63 if (StartUpCounter > LSE_STARTUP_TIMEOUT) {
mbed_official 170:bfbcaf535cca 64 // The LSE has not started, use LSI instead.
mbed_official 170:bfbcaf535cca 65 // The RTC Clock may vary due to LSI frequency dispersion.
mbed_official 170:bfbcaf535cca 66 RCC_LSEConfig(RCC_LSE_OFF);
mbed_official 170:bfbcaf535cca 67 RCC_LSICmd(ENABLE); // Enable LSI
mbed_official 170:bfbcaf535cca 68 while (RCC_GetFlagStatus(RCC_FLAG_LSIRDY) == RESET) {} // Wait until ready
mbed_official 170:bfbcaf535cca 69 RCC_RTCCLKConfig(RCC_RTCCLKSource_LSI); // Select the RTC Clock Source
mbed_official 170:bfbcaf535cca 70 rtc_freq = 40000; // [TODO] To be measured precisely using a timer input capture
mbed_official 170:bfbcaf535cca 71 }
mbed_official 170:bfbcaf535cca 72 else {
mbed_official 170:bfbcaf535cca 73 // The LSE has correctly started
mbed_official 170:bfbcaf535cca 74 RCC_RTCCLKConfig(RCC_RTCCLKSource_LSE); // Select the RTC Clock Source
mbed_official 170:bfbcaf535cca 75 rtc_freq = LSE_VALUE;
mbed_official 170:bfbcaf535cca 76 }
mbed_official 170:bfbcaf535cca 77
mbed_official 170:bfbcaf535cca 78 RCC_RTCCLKCmd(ENABLE); // Enable RTC Clock
mbed_official 170:bfbcaf535cca 79
mbed_official 125:23cc3068a9e4 80 RTC_WaitForSynchro(); // Wait for RTC registers synchronization
mbed_official 125:23cc3068a9e4 81
mbed_official 125:23cc3068a9e4 82 RTC_InitTypeDef RTC_InitStructure;
mbed_official 125:23cc3068a9e4 83 RTC_InitStructure.RTC_AsynchPrediv = 127;
mbed_official 170:bfbcaf535cca 84 RTC_InitStructure.RTC_SynchPrediv = (rtc_freq / 128) - 1;
mbed_official 125:23cc3068a9e4 85 RTC_InitStructure.RTC_HourFormat = RTC_HourFormat_24;
mbed_official 125:23cc3068a9e4 86 RTC_Init(&RTC_InitStructure);
mbed_official 170:bfbcaf535cca 87
mbed_official 170:bfbcaf535cca 88 PWR_BackupAccessCmd(DISABLE); // Disable access to Backup domain
mbed_official 170:bfbcaf535cca 89
mbed_official 125:23cc3068a9e4 90 rtc_inited = 1;
mbed_official 125:23cc3068a9e4 91 }
mbed_official 125:23cc3068a9e4 92
mbed_official 125:23cc3068a9e4 93 void rtc_free(void) {
mbed_official 125:23cc3068a9e4 94 RCC_DeInit(); // Resets the RCC clock configuration to the default reset state
mbed_official 125:23cc3068a9e4 95 rtc_inited = 0;
mbed_official 125:23cc3068a9e4 96 }
mbed_official 125:23cc3068a9e4 97
mbed_official 125:23cc3068a9e4 98 int rtc_isenabled(void) {
mbed_official 125:23cc3068a9e4 99 return rtc_inited;
mbed_official 125:23cc3068a9e4 100 }
mbed_official 125:23cc3068a9e4 101
mbed_official 125:23cc3068a9e4 102 /*
mbed_official 125:23cc3068a9e4 103 RTC Registers
mbed_official 125:23cc3068a9e4 104 RTC_WeekDay 1=monday, 2=tuesday, ..., 7=sunday
mbed_official 125:23cc3068a9e4 105 RTC_Month 1=january, 2=february, ..., 12=december
mbed_official 125:23cc3068a9e4 106 RTC_Date day of the month 1-31
mbed_official 125:23cc3068a9e4 107 RTC_Year year 0-99
mbed_official 125:23cc3068a9e4 108 struct tm
mbed_official 125:23cc3068a9e4 109 tm_sec seconds after the minute 0-61
mbed_official 125:23cc3068a9e4 110 tm_min minutes after the hour 0-59
mbed_official 125:23cc3068a9e4 111 tm_hour hours since midnight 0-23
mbed_official 125:23cc3068a9e4 112 tm_mday day of the month 1-31
mbed_official 125:23cc3068a9e4 113 tm_mon months since January 0-11
mbed_official 125:23cc3068a9e4 114 tm_year years since 1900
mbed_official 125:23cc3068a9e4 115 tm_wday days since Sunday 0-6
mbed_official 125:23cc3068a9e4 116 tm_yday days since January 1 0-365
mbed_official 125:23cc3068a9e4 117 tm_isdst Daylight Saving Time flag
mbed_official 125:23cc3068a9e4 118 */
mbed_official 125:23cc3068a9e4 119 time_t rtc_read(void) {
mbed_official 125:23cc3068a9e4 120 RTC_DateTypeDef dateStruct;
mbed_official 125:23cc3068a9e4 121 RTC_TimeTypeDef timeStruct;
mbed_official 125:23cc3068a9e4 122 struct tm timeinfo;
mbed_official 135:067cc8ba23da 123
mbed_official 125:23cc3068a9e4 124 // Read actual date and time
mbed_official 125:23cc3068a9e4 125 RTC_GetTime(RTC_Format_BIN, &timeStruct);
mbed_official 125:23cc3068a9e4 126 RTC_GetDate(RTC_Format_BIN, &dateStruct);
mbed_official 135:067cc8ba23da 127
mbed_official 125:23cc3068a9e4 128 // Setup a tm structure based on the RTC
mbed_official 125:23cc3068a9e4 129 timeinfo.tm_wday = dateStruct.RTC_WeekDay;
mbed_official 125:23cc3068a9e4 130 timeinfo.tm_mon = dateStruct.RTC_Month - 1;
mbed_official 125:23cc3068a9e4 131 timeinfo.tm_mday = dateStruct.RTC_Date;
mbed_official 125:23cc3068a9e4 132 timeinfo.tm_year = dateStruct.RTC_Year + 100;
mbed_official 125:23cc3068a9e4 133 timeinfo.tm_hour = timeStruct.RTC_Hours;
mbed_official 125:23cc3068a9e4 134 timeinfo.tm_min = timeStruct.RTC_Minutes;
mbed_official 125:23cc3068a9e4 135 timeinfo.tm_sec = timeStruct.RTC_Seconds;
mbed_official 135:067cc8ba23da 136
mbed_official 125:23cc3068a9e4 137 // Convert to timestamp
mbed_official 125:23cc3068a9e4 138 time_t t = mktime(&timeinfo);
mbed_official 135:067cc8ba23da 139
mbed_official 135:067cc8ba23da 140 return t;
mbed_official 125:23cc3068a9e4 141 }
mbed_official 125:23cc3068a9e4 142
mbed_official 125:23cc3068a9e4 143 void rtc_write(time_t t) {
mbed_official 125:23cc3068a9e4 144 RTC_DateTypeDef dateStruct;
mbed_official 125:23cc3068a9e4 145 RTC_TimeTypeDef timeStruct;
mbed_official 125:23cc3068a9e4 146
mbed_official 125:23cc3068a9e4 147 // Convert the time into a tm
mbed_official 125:23cc3068a9e4 148 struct tm *timeinfo = localtime(&t);
mbed_official 135:067cc8ba23da 149
mbed_official 125:23cc3068a9e4 150 // Fill RTC structures
mbed_official 125:23cc3068a9e4 151 dateStruct.RTC_WeekDay = timeinfo->tm_wday;
mbed_official 125:23cc3068a9e4 152 dateStruct.RTC_Month = timeinfo->tm_mon + 1;
mbed_official 125:23cc3068a9e4 153 dateStruct.RTC_Date = timeinfo->tm_mday;
mbed_official 125:23cc3068a9e4 154 dateStruct.RTC_Year = timeinfo->tm_year - 100;
mbed_official 125:23cc3068a9e4 155 timeStruct.RTC_Hours = timeinfo->tm_hour;
mbed_official 125:23cc3068a9e4 156 timeStruct.RTC_Minutes = timeinfo->tm_min;
mbed_official 125:23cc3068a9e4 157 timeStruct.RTC_Seconds = timeinfo->tm_sec;
mbed_official 125:23cc3068a9e4 158 timeStruct.RTC_H12 = RTC_HourFormat_24;
mbed_official 135:067cc8ba23da 159
mbed_official 125:23cc3068a9e4 160 // Change the RTC current date/time
mbed_official 135:067cc8ba23da 161 PWR_BackupAccessCmd(ENABLE); // Enable access to RTC
mbed_official 125:23cc3068a9e4 162 RTC_SetDate(RTC_Format_BIN, &dateStruct);
mbed_official 135:067cc8ba23da 163 RTC_SetTime(RTC_Format_BIN, &timeStruct);
mbed_official 125:23cc3068a9e4 164 PWR_BackupAccessCmd(DISABLE); // Disable access to RTC
mbed_official 125:23cc3068a9e4 165 }
mbed_official 162:937d965048d3 166
mbed_official 162:937d965048d3 167 #endif