STM32-HAL-DS1307

Overview

This is a simple library for STM32 32-bit Arm Cortex MCUs to work with the DS1307 RTC module.

To develop this library it was used STM32CubeIDE and HAL APIs to interact with peripherals and low-level resources.

In this repository you will find the RTC library, ready to attach to your new project and a project example, tested with the STM32F4DISCOVERY board.

Examples

SMT32F4DISCOVERY

Brief description of the example attached

#include "rtc.h"
#include <stdio.h"
int main(){
  RTC_HandleTypeDef rtc;
  RTC_time_t current_time;
  RTC_date_t current_date;

  if (rtc_init(&rtc, &hi2c2)){
	printf("RTC init has failed\n");
	while(1);
  }

  current_date.day = SUNDAY;
  current_date.date = 31;
  current_date.month = 12;
  current_date.year = 15;

  current_time.hours = 11;
  current_time.minutes = 59;
  current_time.seconds = 41;
  current_time.time_format = TIME_FORMAT_12HRS_PM;

  rtc_set_current_time(&rtc, &current_time);
  rtc_set_current_date(&rtc, &current_date);

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
	  rtc_get_current_date(&rtc, &current_date);
	  rtc_get_current_time(&rtc, &current_time);

	  char *am_pm;
	  if (current_time.time_format != TIME_FORMAT_24HRS){
	  	am_pm = (current_time.time_format) ? "PM" : "AM";
	  	printf("Current time = %s %s\n", time_to_string(&current_time), am_pm); // 04:25:41 PM
	  }else {
		  printf("Current_time = %s\n", time_to_string(&current_time)); // 04:25:41
	  }

	  printf("Current date: %s <%s>\n", date_to_string(&current_date), DAY_OF_WEEK(current_date.day));
	  HAL_Delay(1000);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */

}

In this example it's shown how to set an initial time and date and then print the results formatted every second.

Print characters using ITM feature

To see the results of this example it's neccesary to implement the printf like feature using ARM Cortex M3/M4/ ITM functionality. To achieve this, it's necessary to follow the following procedure: https://medium.com/@g.bharathraj19/getting-started-with-instrumentation-trace-macrocell-in-stm32cubeide-4af179eb0034

Documentation

A brief documentation of the structures and functions provided by the library are shown below. For detailed instructions, refer to the doxygen compliant documentation within the rtc.c file.

Macro definitions

List of important macro definitions with a brief description is shown below.

Name	Description
RTC_I2C_ADDRESS	Device address.

Structure

List of structures provided with the library with a brief description is shown below.

Name	Description
RTC_date_t	Struct to handle the parameters related to the date
RTC_time_t	Struct to handle the parameters related to the time
RTC_HandleTypeDef	Struct to handle the I2C device address and the I2C Handler

Functions

List of functions provided with the library with a brief description is shown below.

Name	Description
rtc_init	Initialize the RTC module.
rtc_set_current_time	Set the initial time provided by the user
rtc_get_current_time	Get the current time
rtc_set_current_date	Set the initial date provided by the user
rtc_get_current_date	Get the current date