Ported: JChristensen/DS3232RTC

Thanks

I’m not sure if you are aware but the STM32 has its own internal real time clock which uses an external 32kHz crystal, I think @ahull is the expert in this, and some boards need modification to run from batteries in low power mode.

But its still worth pointing out this built in feature

Hi, I’ve taken this lib (I need a timestamp for the sdfat)
The port can be found here: https://github.com/KenjutsuGH/DS3232RTC.git
but I cannot get it compiled (Maple Mini, 1.6.5), for example
#include <DS3232RTC.h>
#include <Time.h>
#include <Wire.h>

post the errors

I recall there are issues with the various versions of time library

I think @ahull may have an STM32 friendly version of that lib that he used for his PigOScope

I’ve downloaded PaulS “Time” library and renamed the original Arduino one to “TimeAr”.
Now I get following error:
C:\Users\pito\AppData\Local\Temp\build68236732788381724.tmp\Wire\utility\twi.c.o
C:\Users\pito\MyCode\Arduino\libraries\Wire\utility\twi.c:25:20: fatal error: avr/io.h: No such file or directory
#include <avr/io.h>
^
compilation terminated.
Multiple libraries were found for "Wire.h"
Used: C:\Users\pito\MyCode\Arduino\libraries\Wire
Not used: C:\Users\pito\MyCode\Arduino\hardware\Arduino_STM32\STM32F1\libraries\Wire
Error compiling.

Ok it seems it works (SDA1, SCL1)
Start
8:43:23 8 5 2016

If you are interested in using the built in RTC on the STM32F103, you might like to take a look at this project.

More details here.

Code is here.

Image

@ahull – nice project!
I like the DS3231 module as it is precise – in 6months it did +6sec, so I added Aging reg writing to the lib and with +4 written into it may happen I will do a single second off per year
Oscillators with 32kHz fork resonator – you must tune them – a pF capacitance change does few seconds a day, moreover there is no temperature compensation. Of course, still ok for most apps.

Pito wrote:@ahull – nice project!
I like the DS3231 module as it is precise – in 6months it did +6sec, so I added Aging reg writing to the lib and with +4 written into it may happen I will do a single second off per year
Oscillators with 32kHz fork resonator – you must tune them – a pF capacitance change does few seconds a day, moreover there is no temperature compensation. Of course, still ok for most apps.

I like this video:
https://www.youtube.com/watch?v=Jp2BOBIzSE0
and my wish list
DS3231tuning.JPG

ahull wrote:For anything more precise, GPS or NTP (using an ESP8266 perhaps) or “mobile phone time” are probably the simplest options.

Kenjutsu wrote:I ported the DS3232RTC library of JChristensen and tested it with a DS3231 AT24C32 IIC module precision Real time clock module memory module Arduino. I only tested the SetSerial.ino example program.
The port can be found here: https://github.com/KenjutsuGH/DS3232RTC.git

Hello !

my project

#include <DS3232RTC.h> //http://github.com/JChristensen/DS3232RTC
#include "Time.h"
#include <TimeLib.h>

time_t t1;
time_t t2;

tmElements_t tm;

t1=RTC.get();
t2=now();

If you look at the DS3232RTC library code, it is returning 0 if it is not able to read the RTC on I2C bus.
So, you need to debug that … Maybe your wiring is wrong, maybe you forgot to have pull-ups, etc …

No.
the clock is right.
if you disconnect the power wire from the clock module – clock-stop.
If you set a time and do not remove the battery from the module , the time is read correctly.
But if the battery is removed – the time is reset to 1970.
I think that the problem is to link new libraries<TimeLib.h> and <DS3232RTC.h> .
https://github.com/PaulStoffregen/Time

I’ve created a very simple rtc library, uRTCLib. If your library is reading rtc correctly check math operations, probably there is a type problem (32 bits vs 8 bits operation).

Just a quick note: Updated to the latest version of DS3232RTC library of JChristensen