118 lines
5.0 KiB
Plaintext
118 lines
5.0 KiB
Plaintext
/**
|
|
@page RTC_Calendar RTC Calendar Example
|
|
|
|
@verbatim
|
|
******************************************************************************
|
|
* @file RTC/RTC_Calendar/readme.txt
|
|
* @author MCD Application Team
|
|
* @brief Description of the RTC Calendar example.
|
|
******************************************************************************
|
|
*
|
|
* Copyright (c) 2020 STMicroelectronics. All rights reserved.
|
|
*
|
|
* This software component is licensed by ST under BSD 3-Clause license,
|
|
* the "License"; You may not use this file except in compliance with the
|
|
* License. You may obtain a copy of the License at:
|
|
* opensource.org/licenses/BSD-3-Clause
|
|
*
|
|
******************************************************************************
|
|
@endverbatim
|
|
|
|
@par Example Description
|
|
|
|
Configuration of the calendar using the RTC HAL API.
|
|
|
|
At the beginning of the main program the HAL_Init() function is called to reset
|
|
all the peripherals, initialize the Flash interface and the systick.
|
|
Then the SystemClock_Config() function is used to configure the system
|
|
clock (SYSCLK) to run at 48 MHz.
|
|
|
|
The RTC peripheral configuration is ensured by the HAL_RTC_Init() function.
|
|
This later is calling the HAL_RTC_MspInit()function which core is implementing
|
|
the configuration of the needed RTC resources according to the used hardware (CLOCK,
|
|
PWR, RTC clock source and BackUp). You may update this function to change RTC configuration.
|
|
|
|
LSI oscillator clock is used as RTC clock source.
|
|
The user can use also LSE as RTC clock source.
|
|
- The user uncomment the adequate line on the main.c file.
|
|
@code
|
|
#define RTC_CLOCK_SOURCE_LSI
|
|
/* #define RTC_CLOCK_SOURCE_LSE */
|
|
@endcode
|
|
- Open the ioc file with STM32CubeMX and select :
|
|
LSE as "Crystal/Ceramic Resonator" in RCC configuration.
|
|
LSE as RTC clock source in Clock configuration.
|
|
- Generate code
|
|
LSI oscillator clock is delivered by a 32 kHz.
|
|
LSE (when available on board) is delivered by a 32.768 kHz crystal.
|
|
|
|
HAL_RTC_SetTime()and HAL_RTC_SetDate() functions are then called to initialize the
|
|
time and the date.
|
|
|
|
A key value is written in backup data register 1 to indicate if the RTC is already configured.
|
|
The program behaves as follows:
|
|
|
|
1. After startup the program checks the backup data register 0 value:
|
|
- BKP_DR0 value not correct: (RTC_BKP_DR0 value is not correct or has not yet
|
|
been programmed when the program is executed for the first time) the RTC is
|
|
configured and internal time stamp is enabled.
|
|
|
|
- BKP_DR0 value correct: this means that the RTC is configured and the time
|
|
and date are displayed on Debugger.
|
|
|
|
2. When a reset (except power on reset) occurs the BKP domain is not reset and the RTC
|
|
configuration is not lost. LED1 is ON.
|
|
|
|
3. When power on reset occurs:
|
|
- The BKP domain is reset and the RTC configuration is lost.
|
|
Note: During first debugger re-run, the power on reset already occurred just before
|
|
(at switch ON) then RTC configuration is not lost and LED3 is ON.
|
|
|
|
LED2 is turned ON when the RTC configuration is done correctly.
|
|
|
|
|
|
The current time and date are updated and displayed on the debugger in aShowTime
|
|
and aShowDate variables.
|
|
|
|
@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
|
|
based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
|
|
a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
|
|
than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
|
|
To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
|
|
|
|
@note The application need to ensure that the SysTick time base is always set to 1 millisecond
|
|
to have correct HAL operation.
|
|
|
|
@par Keywords
|
|
|
|
System, RTC, Calendar, Backup Domain, Reset
|
|
|
|
@par Directory contents
|
|
|
|
- RTC/RTC_Calendar/Inc/stm32wlxx_nucleo_conf.h BSP configuration file
|
|
- RTC/RTC_Calendar/Inc/stm32wlxx_hal_conf.h HAL configuration file
|
|
- RTC/RTC_Calendar/Inc/stm32wlxx_it.h Interrupt handlers header file
|
|
- RTC/RTC_Calendar/Inc/main.h Header for main.c module
|
|
- RTC/RTC_Calendar/Src/stm32wlxx_it.c Interrupt handlers
|
|
- RTC/RTC_Calendar/Src/main.c Main program
|
|
- RTC/RTC_Calendar/Src/stm32wlxx_hal_msp.c HAL MSP module
|
|
- RTC/RTC_Calendar/Src/system_stm32wlxx.c STM32WLxx system source file
|
|
|
|
|
|
@par Hardware and Software environment
|
|
|
|
- This example runs on STM32WL55JCIx Devices.
|
|
- This example has been tested with STMicroelectronics NUCLEO-WL55JC RevC
|
|
board and can be easily tailored to any other supported device and
|
|
development board.
|
|
|
|
@par How to use it ?
|
|
|
|
In order to make the program work, you must do the following :
|
|
- Open your preferred toolchain
|
|
- Rebuild all files and load your image into target memory
|
|
- Run the example
|
|
|
|
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
|
|
*/
|