RTC Class
RTC Class
Description
A class used for displaying date and time and alarm configuration using RTC, the independent BCD (Binary-Coded-Decimal) timer.
Syntax
class RTC
Members
| Public Constructors | |
| A public constructor should not be used as this class is intended to be a singleton class. Access member functions using the object instance named RTC. |
| Public Methods | |
| RTC::Init | Initializes the RTC device, including the Clock, the RTC registers, and other functions |
| RTC::DeInit | Deinitialize the RTC device |
| RTC::Write | Set the specified timestamp in seconds to RTC |
| RTC::Read | Get the current timestamp in seconds from RTC |
| RTC::Wait | Wait for 1 second |
| RTC::SetEpoch | Convert human-readable time to epoch time |
RTC::Init
Description
Initializes the RTC device, including the Clock, the RTC registers, and other functions.
Syntax
void RTC::Init(void);
Parameters
The function requires no input parameter.
Returns
The function returns nothing.
Example Code
Example: RTC
/**
* This function describes how to use the RTC API.
* The RTC function is implemented by an independent BCD timer/counter.
* This example will print out the time information every second.
*/
#include "stdio.h"
#include "time.h"
#include "rtc.h"
#define YEAR 2020
#define MONTH 9
#define DAY 10
#define HOUR 20
#define MIN 30
#define SEC 40
/* Create an rtc object */
RTC rtc;
int32_t seconds;
struct tm *timeinfo;
void setup() {
Serial.begin(115200);
rtc.Init(); // initialize RTC
}
void loop() {
// step 1: convert user time to epoch
int epochTime = humanReadableToEpoch(YEAR, MONTH, DAY, HOUR, MIN, SEC);
// step 2: write epoch time to rtc
rtc.Write(epochTime);
while (1) {
seconds = rtc.Read();
printf("Epoch Time (in s) since January 1, 1970 = %ds\n", seconds);
printf("Time as a basic string = %s", ctime(&seconds));
timeinfo = localtime(&seconds);
printf("Time as a custom formatted string = %d-%d-%d %d:%d:%d\n",
(timeinfo->tm_year + 1900), (timeinfo->tm_mon + 1), timeinfo->tm_mday, timeinfo->tm_hour,
timeinfo->tm_min, timeinfo->tm_sec);
Serial.println();
rtc.wait(1);
}
}
// convert human readable time to epoch time
int humanReadableToEpoch(int year, int month, int day, int hour, int min, int sec) {
struct tm t;
time_t t_of_day;
t.tm_year = year - 1900; // Year - 1970
t.tm_mon = month - 1; // Month, where 0 = jan
t.tm_mday = day; // Day of the month
t.tm_hour = hour;
t.tm_min = min;
t.tm_sec = sec;
t.tm_isdst = -1; // Is DST on? 1 = yes, 0 = no, -1 = unknown
t_of_day = mktime(&t);
// printf("seconds since the Epoch: %d\n", (long)t_of_day);
return t_of_day;
}
Notes and Warnings
NA
RTC::DeInit
Description
Deinitializes the RTC device.
Syntax
void RTC::DeInit(void);
Parameters
The function requires no input parameter.
Returns
The function returns nothing.
Example Code
Example: RTC
Details of the code can be found in the previous section of RTC::Init.
Notes and Warnings
NA
RTC::Write
Description
Set the specified timestamp in seconds to RTC. Seconds from 1970.1.1 00:00:00 (YEAR.MONTH.DAY, HOUR: MIN: SECONDS) to specified date and time which is to be set.
Syntax
void RTC::Write(int t);
Parameters
Parameters
t: Seconds from 1970.1.1 00:00:00 (YEAR.MONTH.DAY, HOUR: MIN: SECONDS) to specified date and time which is to be set.
Returns
The function returns nothing.
Example Code
Example: RTC
Details of the code can be found in the previous section of RTC::Init.
Notes and Warnings
NA
RTC::Read
Description
Get the current timestamp in seconds from RTC. The current timestamp in seconds which is calculated from 1970.1.1 00:00:00 (YEAR.MONTH.DAY, HOUR: MIN: SECONDS).
Syntax
int32_t RTC::Read(void);
Parameters
The function requires no input parameter.
Returns
The function returns the current timestamp in seconds which is calculated from 1970.1.1 00:00:00 (YEAR.MONTH.DAY, HOUR: MIN: SECONDS).
Example Code
Example: RTC
Details of the code can be found in the previous section of RTC::Init.
Notes and Warnings
NA
RTC::Wait
Description
Send IR raw data.
Syntax
void RTC::wait(float s);
Parameters
s: unit microseconds (1 us)
Returns
The function returns nothing.
Example Code
Example: RTC
Details of the code can be found in the previous section of RTC::Init.
Notes and Warnings
NA
RTC::SetEpoch
Description
Convert human-readable time to epoch time
Syntax
int RTC::SetEpoch(int year, int month, int day, int hour, int min, int sec);
Parameters
year: user input year
month: user input month
day: user input day
hour: user input hour
min: user input minutes
sec: user input seconds
Returns
The function returns epoch time in seconds for RTC use.
Example Code
Example: RTC
Details of the code can be found in the previous section of RTC::Init.
Notes and Warnings
NA
