RTC Real time clock

Projects Programming
1 
#include <RTClib.h>
#include <Wire.h>

RTC_DS1307 rtc;

char buf1[20];

void setup() 
{
  Serial.begin(9600);
  Wire.begin();

  rtc.begin();
  rtc.adjust(DateTime(F(__DATE__),F(__TIME__)));

}

void loop()
{
  DateTime now = rtc.now();

  sprintf(buf1, "%02d:%02d:%02d %02d/%02d/%02d",  now.hour(), now.minute(), now.second(), now.day(), now.month(), now.year());  
  
  Serial.print(F("Date/Time: "));
  Serial.println(buf1);

  delay(1000);
}

I don't know why the output of the code is always "Date/Time: 165:165:85 165/165/216", and it doesn't change.I am using ESP8266.

2 
char buf1[20];

0123456789012345678901234
165:165:85 165/165/216

For starters, I have a feeling that your sprintf() statement is overflowing buf1.

Before anything else, you should change char buf1[20]; to char buf1[25];

And you might want to double-check that your DS1307 is wired up correctly, has power, etc.

3

odometer:

char buf1[20];

0123456789012345678901234

165:165:85 165/165/216




For starters, I have a feeling that your `sprintf()` statement is overflowing `buf1`.

Before anything else, you should change `char buf1[20];` to `char buf1[25];`

And you might want to double-check that your DS1307 is wired up correctly, has power, etc.

yea same thing
shown "Date/Time: 165:165:85 2165/165/165"

4

Inadequate power? The display you get implies that. Assuming the code is standard stuff, the RTC per se may not be the problem.

5

Hmmm, I think there somewhere in the beginning should be a

#define "ADDRESS" for rtc , for example 0x68