Hi all,
I have problem with RTC modul DS3231.. It is connected to MEGA (SDA 20 and SCL 21) and rapidly speed up (let say 15 seconds on 10 minutes) when I attach EthernetShield W5100. There is still same simple program to read time from RTC modul. (downloaded)
I´m newbie in that and I have no idea how to solve this mystery.. :-/
// DS3231_Serial_Easy (C)2014 Henning Karlsen
// web: http://electronics.henningkarlsen.com/
//
// A quick demo of how to use my DS3231-library to
// quickly send time and date information over a serial link
//
// To use the hardware I2C (TWI) interface of the Arduino you must connect
// the pins as follows:
//
// Arduino Uno/2009:
// ----------------------
// DS3231: SDA pin -> Arduino Analog 4 or the dedicated SDA pin
// SCL pin -> Arduino Analog 5 or the dedicated SCL pin
//
// Arduino Leonardo:
// ----------------------
// DS3231: SDA pin -> Arduino Digital 2 or the dedicated SDA pin
// SCL pin -> Arduino Digital 3 or the dedicated SCL pin
//
// Arduino Mega:
// ----------------------
// DS3231: SDA pin -> Arduino Digital 20 (SDA) or the dedicated SDA pin
// SCL pin -> Arduino Digital 21 (SCL) or the dedicated SCL pin
//
// Arduino Due:
// ----------------------
// DS3231: SDA pin -> Arduino Digital 20 (SDA) or the dedicated SDA1 (Digital 70) pin
// SCL pin -> Arduino Digital 21 (SCL) or the dedicated SCL1 (Digital 71) pin
//
// The internal pull-up resistors will be activated when using the
// hardware I2C interfaces.
//
// You can connect the DS3231 to any available pin but if you use any
// other than what is described above the library will fall back to
// a software-based, TWI-like protocol which will require exclusive access
// to the pins used, and you will also have to use appropriate, external
// pull-up resistors on the data and clock signals.
//
#include <DS3231.h>
// Init the DS3231 using the hardware interface
DS3231 rtc(SDA, SCL);
void setup()
{
// Setup Serial connection
Serial.begin(9600);
// Uncomment the next line if you are using an Arduino Leonardo
//while (!Serial) {}
// Initialize the rtc object
Serial.println("GO");
rtc.begin();
// The following lines can be uncommented to set the date and time
//rtc.setDOW(WEDNESDAY); // Set Day-of-Week to SUNDAY
//rtc.setTime(12, 0, 0); // Set the time to 12:00:00 (24hr format)
//rtc.setDate(1, 1, 2014); // Set the date to January 1st, 2014
}
void loop()
{
// Send Day-of-Week
Serial.print(rtc.getDOWStr());
Serial.print(" ");
// Send date
Serial.print(rtc.getDateStr());
Serial.print(" -- ");
// Send time
Serial.println(rtc.getTimeStr());
// Wait one second before repeating :)
delay (1000);
}