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RTC DS1307 not working with Arduino

Former Member

I am currently trying to interface an RTC with arduino. For this purpose,I am using Tiny RTC module DS1307 purchased from Ebay

My connections are as follows-

Vcc-Vcc

GND-GND

SCL-A5

SDA-A4

 

 

I have downloaded the RTC library from adafruit website and am trying the example code.

 

 

#include <Wire.h>

#include "RTClib.h"

RTC_DS1307 RTC;

 

 

void setup () {

    Serial.begin(9600);

    Wire.begin();

    RTC.begin();

  if (! RTC.isrunning()) {

    Serial.println("RTC is NOT running!");

    // following line sets the RTC to the date & time this sketch was compiled

    RTC.adjust(DateTime(__DATE__, __TIME__));

  }

}

void loop () {

    DateTime now = RTC.now();

    Serial.print(now.year(), DEC);

    Serial.print('/');

    Serial.print(now.month(), DEC);

    Serial.print('/');

    Serial.print(now.day(), DEC);

    Serial.print(' ');

    Serial.print(now.hour(), DEC);

    Serial.print(':');

    Serial.print(now.minute(), DEC);

    Serial.print(':');

    Serial.print(now.second(), DEC);

    Serial.println();

    delay(1000);

}

 

Below is the Screenshot of the output I am getting using Serial monitor. I want to ask why does the output(date and time) come correct for the first time and after that becomes incorrect? I am really confused.

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  • 0

    Second issue is the way your setting and getting the compile time, if you use the Adafruit library (Not sure if they wrote it but who cares right now)  https://github.com/adafruit/RTClib and look at the softrtc example, it works correctly

     

    here is a clip of it

     

    void setup () {
    Serial.begin(57600);
    // following line sets the RTC to the date & time this sketch was compiled
    rtc.begin(DateTime(F(__DATE__), F(__TIME__)));
    // This line sets the RTC with an explicit date & time, for example to set
    // January 21, 2014 at 3am you would call:
    // rtc.adjust(DateTime(2014, 1, 21, 3, 0, 0));
}

     

    so between switching the A4 and A5, and changing the code, it should now work

  • 0 in reply to Robert Peter Oakes

    I know this is an old thread , but I have a fix for this , there is nothing wrong with the code .

    the board has a incorrectly designed connection between RTC chip and backup battery , the fix is remove R4 R6 and D1 , Short R6 connections out , this should give you full battery voltage of 3.2 volts on the RTC chip PIn 3 .Whoever designed this put a 510k resistor in series between the battery and RTC chip , with a diode feeding from 5v .This goes against the manufacturers recommended circuit diagram

     

     

     

    image

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  • 0 in reply to Robert Peter Oakes

    I know this is an old thread , but I have a fix for this , there is nothing wrong with the code .

    the board has a incorrectly designed connection between RTC chip and backup battery , the fix is remove R4 R6 and D1 , Short R6 connections out , this should give you full battery voltage of 3.2 volts on the RTC chip PIn 3 .Whoever designed this put a 510k resistor in series between the battery and RTC chip , with a diode feeding from 5v .This goes against the manufacturers recommended circuit diagram

     

     

     

    image

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