When I upload the program, the result is normal, but until I turn off the power and restart, the top speed of the second run is no longer normal, the normal DS 1307 mercury batteries, the next time Turn on the power to read the time will be normal
// Sketch by brainstorm ABC for I2C Based Clock Using RTC and 16x2 I2c Display
#include <Wire.h>
#include <Time.h>
#include <DS1307RTC.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>
#define I2C_ADDR 0x27 // Define I2C Address for the PCF8574T
//---(Following are the PCF8574 pin assignments to LCD connections )----
// This are different than earlier/different I2C LCD displays
#define Rs_pin 0
#define Rw_pin 1
#define En_pin 2
#define BACKLIGHT_PIN 3
#define D4_pin 4
#define D5_pin 5
#define D6_pin 6
#define D7_pin 7
#define LED_OFF 1
#define LED_ON 0
/-----( Declare objects )-----/
LiquidCrystal_I2C lcd(I2C_ADDR,En_pin,Rw_pin,Rs_pin,D4_pin,D5_pin,D6_pin,D7_pin);
void setup() {
lcd.begin (16,2); // initialize the lcd
// Switch on the backlight
lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
lcd.setBacklight(LED_ON);
}
void loop() {
tmElements_t tm;
// Print our characters on the LCD
lcd.backlight(); //Backlight ON if under program control
if (RTC.read(tm)) {
lcd.setCursor(0,0); //Start at character 0 on line 0
lcd.print("TIME :");
// lcd.setCursor(6,0);
print2digits(tm.Hour);
lcd.print(':');
print2digits(tm.Minute);
lcd.print(':');
print2digits(tm.Second);
lcd.setCursor(0,1); //Start at character 0 on line 1
lcd.print("DATE :");
lcd.print(tm.Day);
lcd.print('/');
lcd.print(tm.Month);
lcd.print('/');
lcd.print(tmYearToCalendar(tm.Year));
}
delay(990);
}
void print2digits(int number) {
if (number >= 0 && number < 10) {
lcd.print('0');
}
lcd.print(number);
}
