This is a RTC additional function. This is only for Nucleo F401RE & F411RE mbed(Added L152RE, F334R8, L476RG & F746xx). If you connected battery backup circuit for internal RTC, you can make a power-off and reset condition. RTC still has proper time and date.

Dependents:   Nucleo_rtos_sample PB_Emma_Ethernet

Please refer following NOTE information.
/users/kenjiArai/notebook/nucleo-series-rtc-control-under-power-onoff-and-re/

Revision:
13:44e5327acb05
Parent:
12:4074fe3e67c7
Child:
14:78e453d7bb85
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/modify_info_L476.h	Fri May 27 20:16:09 2016 +0000
@@ -0,0 +1,28 @@
+/*
+ * mbed Application program
+ *      Library differ part (This is only information document)
+ *
+ * Copyright (c) 2016 Kenji Arai / JH1PJL
+ *  http://www.page.sannet.ne.jp/kenjia/index.html
+ *  http://mbed.org/users/kenjiArai/
+ *      Created: May       28th, 2016
+ *      Revised: May       28th, 2016
+ *
+ * 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
+ * AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+//*************************************************************************************************
+//  Replace following files in the library
+//      rtc_api.c -> rtc_api_L476.c
+//*************************************************************************************************
+//
+// (1) Update mbed-dev library if you want
+// (2) File rtc_api_L152.c copy to directry
+//     /mbed-dev/targets/hal/TARGET_STM/TARGET_STM32L4/
+// (3) Delete rtc_api.c in the same directory
+// (4) Edit rtc_api_L476.c
+//     Modify 1st line #if 0 --> #if 1
+//