Diff: targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c

Revision:

4:4a8e88c1ef9e

Parent:

0:9b334a45a8ff

Child:

34:bb6061527455

diff -r 457d224d8af1 -r 4a8e88c1ef9e targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c
--- a/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c	Tue Oct 06 12:00:11 2015 +0100
+++ b/targets/hal/TARGET_STM/TARGET_STM32F7/rtc_api.c	Tue Oct 06 13:15:09 2015 +0100
@@ -33,8 +33,6 @@
 
 #include "mbed_error.h"
 
-static int rtc_inited = 0;
-
 static RTC_HandleTypeDef RtcHandle;
 
 void rtc_init(void)
@@ -42,58 +40,59 @@
     RCC_OscInitTypeDef RCC_OscInitStruct;
     uint32_t rtc_freq = 0;
 
-    if (rtc_inited) return;
-    rtc_inited = 1;
+    if(RTC->ISR == 7) {     // RTC initialization and status register (RTC_ISR), cold start (with no backup domain power) RTC reset value
 
-    RtcHandle.Instance = RTC;
+        RtcHandle.Instance = RTC;
+
+        // Enable Power clock
+        __PWR_CLK_ENABLE();
 
-    // Enable Power clock
-    __PWR_CLK_ENABLE();
+        // Enable access to Backup domain
+        HAL_PWR_EnableBkUpAccess();
 
-    // Enable access to Backup domain
-    HAL_PWR_EnableBkUpAccess();
-
-    // Reset Backup domain
-    __HAL_RCC_BACKUPRESET_FORCE();
-    __HAL_RCC_BACKUPRESET_RELEASE();
+        // Reset Backup domain
+        __HAL_RCC_BACKUPRESET_FORCE();
+        __HAL_RCC_BACKUPRESET_RELEASE();
 
-    // Enable LSE Oscillator
-    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
-    RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; // Mandatory, otherwise the PLL is reconfigured!
-    RCC_OscInitStruct.LSEState       = RCC_LSE_ON; // External 32.768 kHz clock on OSC_IN/OSC_OUT
-    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) == HAL_OK) {
-        // Connect LSE to RTC
-        __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSE);
-        __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSE);
-        rtc_freq = LSE_VALUE;
-    } else {
-        // Enable LSI clock
-        RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
+        // Enable LSE Oscillator
+        RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
         RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; // Mandatory, otherwise the PLL is reconfigured!
-        RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
-        RCC_OscInitStruct.LSIState       = RCC_LSI_ON;
-        if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
-            error("RTC error: LSI clock initialization failed.");
+        RCC_OscInitStruct.LSEState       = RCC_LSE_ON; // External 32.768 kHz clock on OSC_IN/OSC_OUT
+        if (HAL_RCC_OscConfig(&RCC_OscInitStruct) == HAL_OK) {
+            // Connect LSE to RTC
+            __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSE);
+            __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSE);
+            rtc_freq = LSE_VALUE;
+        } else {
+            // Enable LSI clock
+            RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
+            RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; // Mandatory, otherwise the PLL is reconfigured!
+            RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
+            RCC_OscInitStruct.LSIState       = RCC_LSI_ON;
+            if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+                error("RTC error: LSI clock initialization failed.");
+            }
+            // Connect LSI to RTC
+            __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSI);
+            __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSI);
+            // [TODO] This value is LSI typical value. To be measured precisely using a timer input capture
+            rtc_freq = LSI_VALUE;
         }
-        // Connect LSI to RTC
-        __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSI);
-        __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSI);
-        // [TODO] This value is LSI typical value. To be measured precisely using a timer input capture
-        rtc_freq = LSI_VALUE;
-    }
 
-    // Enable RTC
-    __HAL_RCC_RTC_ENABLE();
+        // Enable RTC
+        __HAL_RCC_RTC_ENABLE();
 
-    RtcHandle.Init.HourFormat     = RTC_HOURFORMAT_24;
-    RtcHandle.Init.AsynchPrediv   = 127;
-    RtcHandle.Init.SynchPrediv    = (rtc_freq / 128) - 1;
-    RtcHandle.Init.OutPut         = RTC_OUTPUT_DISABLE;
-    RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
-    RtcHandle.Init.OutPutType     = RTC_OUTPUT_TYPE_OPENDRAIN;
+        RtcHandle.Init.HourFormat     = RTC_HOURFORMAT_24;
+        RtcHandle.Init.AsynchPrediv   = 127;
+        RtcHandle.Init.SynchPrediv    = (rtc_freq / 128) - 1;
+        RtcHandle.Init.OutPut         = RTC_OUTPUT_DISABLE;
+        RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
+        RtcHandle.Init.OutPutType     = RTC_OUTPUT_TYPE_OPENDRAIN;
 
-    if (HAL_RTC_Init(&RtcHandle) != HAL_OK) {
-        error("RTC error: RTC initialization failed.");
+        if (HAL_RTC_Init(&RtcHandle) != HAL_OK) {
+            error("RTC error: RTC initialization failed.");
+        }
+
     }
 }
 
@@ -119,13 +118,15 @@
     RCC_OscInitStruct.LSIState       = RCC_LSI_OFF;
     RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
     HAL_RCC_OscConfig(&RCC_OscInitStruct);
-
-    rtc_inited = 0;
 }
 
 int rtc_isenabled(void)
 {
-    return rtc_inited;
+    if(RTC->ISR != 7) {
+        return 1;
+    } else {
+        return 0;
+    }
 }
 
 /*
@@ -180,6 +181,9 @@
 
     RtcHandle.Instance = RTC;
 
+    // Enable write access to Backup domain
+    HAL_PWR_EnableBkUpAccess();
+
     // Convert the time into a tm
     struct tm *timeinfo = localtime(&t);