RTC_TimeStamp Example Description

Configuration of the RTC HAL API to demonstrate the timestamp feature.

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.

HAL_RTCEx_SetTimeStamp_IT()function is then called to initialize the time stamp feature with interrupt mode. It configures the time stamp pin to be rising edge and enables the time stamp detection on time stamp pin.

HAL_RTC_SetTime()and HAL_RTC_SetDate() functions are then called to initialize the time and the date.

The associated firmware performs the following:

  1. After startup the program configure the RTC (Time date) and enable the feature timeStamp.

  2. When applying a high level on the time stamp pin (PC.13) by pressing the User push-button, a time stamp event is detected and the calendar is saved in the time stamp structures. Each time the user presses on the User push-button, the current time and date are updated and displayed on the debugger in aShowTime and aShowDate variables . The current time and date stamp are updated and displayed on the debugger in aShowDateStamp and aShowTimeStamp variables .

Notes

  1. 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.

  2. The application need to ensure that the SysTick time base is always set to 1 millisecond to have correct HAL operation.

Keywords

RTC, Timer, Timestamp, Counter, LSE, LSI, Current time, Real Time Clock

Directory contents

Hardware and Software environment

How to use it ?

In order to make the program work, you must do the following :