Maxim Ibragimov / Nucleo_F103RB_RTC_battery_bkup_pwr_off_okay

Solution how to fix broken RTC on Nucleo_F103RB / STM32F103 BluePill etc..

Dependencies:   mbed-dev

Fork of Nucleo_RTC_battery_bkup_pwr_off_okay by Kenji Arai

Experimental fork https://os.mbed.com/users/kenjiArai/code/Nucleo_RTC_battery_bkup_pwr_off_okay/ to fix broken RTC on Nucleo_F103RB / STM32F103 BluePill etc..

At this moment (7/11/17) use forked mbed-dev https://os.mbed.com/users/maxxir/code/mbed-dev/.

Or require patch for ./mbed-dev/targets/TARGET_STM/rtc_api.c.

You can manual add to your project fresh mbed-dev and change file mbed-dev\targets\TARGET_STM\rtc_api.c from root project patched rtc_api.c.stm32f10x.txt.

Exploring origin errors, I saw that something wrong with HAL API on STM32F1xx with this functions:

 HAL_RTC_GetTime(&RtcHandle, &timeStruct, RTC_FORMAT_BIN);

 HAL_RTC_GetDate(&RtcHandle, &dateStruct, RTC_FORMAT_BIN);


 HAL_RTC_SetDate(&RtcHandle, &dateStruct, RTC_FORMAT_BIN);

 HAL_RTC_SetTime(&RtcHandle, &timeStruct, RTC_FORMAT_BIN);

Look here (as I understand it possible broken on STM32CUBE HAL level now):

https://community.st.com/thread/43218-stm32f103-loss-rtc-date-when-reset

So I use direct RTC register manipulation for STM32F1xx:

rtc_read(), rtc_write() (native rtc_init() - works good).

Also added stub for non-working on STM32F1xx rtc_read_subseconds().

Now the stm32F103 can survive power off, and allows you to get and set the time.

Tested OK on boards:

NUCLEO STM32F103RB, DIY STM32F100CB (forked from DISCO_F100RB)

Happy coding!

maxxir

10/11/17

Diff: main.cpp

Revision:
5:bc464a588c2e
Parent:
4:a9cebfe4715f
Child:
6:5ada291037aa
--- a/main.cpp	Thu Feb 19 02:59:11 2015 +0000
+++ b/main.cpp	Sat May 23 22:26:37 2015 +0000
@@ -6,7 +6,7 @@
  *  http://www.page.sannet.ne.jp/kenjia/index.html
  *  http://mbed.org/users/kenjiArai/
  *      Created: January   17th, 2015
- *      Revised: Feburary  19th, 2015
+ *      Revised: May       24th, 2015
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
  * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
@@ -26,9 +26,10 @@
 
 #define USE_LCD
 
-#if defined(TARGET_NUCLEO_F401RE) || defined(TARGET_NUCLEO_F411RE) || defined(TARGET_NUCLEO_L152RE)
+#if defined(TARGET_NUCLEO_F401RE) || defined(TARGET_NUCLEO_F411RE) \
+ || defined(TARGET_NUCLEO_L152RE) || defined(TARGET_NUCLEO_F334R8)
 #else
-#error "Target is only Nucleo F401RE, F411RE and L152RE"
+#error "Target is only Nucleo F401RE, F411RE, F334R8 and L152RE"
 #endif
 
 //  Object ----------------------------------------------------------------------------------------
@@ -69,7 +70,7 @@
 #endif
     pc.printf("\r\n\r\nTest Nucleo RTC Function\r\n");
     myled = !myled;
-    if (SetRTC() == 1) {
+    if (SetRTC(0) == 1) {
         pc.printf("External");
         xtal = 1;
     } else {