https://github.com/walidabazo/how-to-use-external-real-time-clock-rtc-with-wemos-esp8266
https://github.com/walidabazo/how-to-use-external-real-time-clock-rtc-with-wemos-esp8266
Last synced: about 2 months ago
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- Host: GitHub
- URL: https://github.com/walidabazo/how-to-use-external-real-time-clock-rtc-with-wemos-esp8266
- Owner: walidabazo
- Created: 2024-08-28T19:28:08.000Z (8 months ago)
- Default Branch: main
- Last Pushed: 2024-08-28T19:41:04.000Z (8 months ago)
- Last Synced: 2025-01-09T17:04:18.906Z (4 months ago)
- Size: 4.88 KB
- Stars: 1
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# How-to-Use-External-Real-Time-Clock-RTC-with-Wemos-Esp8266
// hd44780 library see https://github.com/duinoWitchery/hd44780
// thehd44780 library is available through the IDE library manager
#include
#include // main hd44780 header
#include // i2c expander i/o class header
#include
#include
ThreeWire myWire(D4,D5,D3); // IO, SCLK, CE
RtcDS1302 Rtc(myWire);
hd44780_I2Cexp lcd; // declare lcd object: auto locate & auto config expander chip
// LCD geometry
const int LCD_COLS = 16;
const int LCD_ROWS = 2;
void setup()
{
Serial.begin(57600);
lcd.begin(LCD_COLS, LCD_ROWS);
lcd.clear();
lcd.backlight();
Serial.print("compiled: ");
Serial.print(__DATE__);
Serial.println(__TIME__);
Rtc.Begin();
RtcDateTime compiled = RtcDateTime(__DATE__, __TIME__);
printDateTime(compiled);
Serial.println();
if (!Rtc.IsDateTimeValid())
{
// Common Causes:
// 1) first time you ran and the device wasn't running yet
// 2) the battery on the device is low or even missing
Serial.println("RTC lost confidence in the DateTime!");
Rtc.SetDateTime(compiled);
}
if (Rtc.GetIsWriteProtected())
{
Serial.println("RTC was write protected, enabling writing now");
Rtc.SetIsWriteProtected(false);
}
if (!Rtc.GetIsRunning())
{
Serial.println("RTC was not actively running, starting now");
Rtc.SetIsRunning(true);
}
RtcDateTime now = Rtc.GetDateTime();
if (now < compiled)
{
Serial.println("RTC is older than compile time! (Updating DateTime)");
Rtc.SetDateTime(compiled);
}
else if (now > compiled)
{
Serial.println("RTC is newer than compile time. (this is expected)");
}
else if (now == compiled)
{
Serial.println("RTC is the same as compile time! (not expected but all is fine)");
}
lcd.print("Hello World");
lcd.setCursor(0, 1);
lcd.print("Clock ");
}
void loop()
{
// updateLCD();
RtcDateTime now = Rtc.GetDateTime();
printDateTime(now);
Serial.println();
if (!now.IsValid())
{
// Common Causes:
// 1) the battery on the device is low or even missing and the power line was disconnected
Serial.println("RTC lost confidence in the DateTime!");
}
delay(10000); // ten seconds
}
#define countof(a) (sizeof(a) / sizeof(a[0]))
void printDateTime(const RtcDateTime& dt)
{
lcd.clear();
//24 Hours
// char datestring[20];
// snprintf_P(datestring,
// countof(datestring),
// PSTR("%02u/%02u/%04u %02u:%02u:%02u"),
// dt.Month(),
// dt.Day(),
// dt.Year(),
// dt.Hour();
// dt.Minute(),
// dt.Second() );
// Serial.print(datestring);
// lcd.print(datestring);
// 12 AM PM
const uint8_t h = dt.Hour();
const uint8_t hr_12 = h%12;
const uint8_t hrw=h%12;
String AMPM = (h < 12) ? " AM" : " PM" ;
if(hr_12 < 10){
hrw == (h > 12) ? h - 12 : ((h == 0) ? 12 : h), DEC;
}
else
{
hrw == ((h > 12) ? h - 12 : ((h == 0) ? 12 : h), DEC);
}
char datestrings[10];
snprintf_P(datestrings,
countof(datestrings),
PSTR(" %02u:%02u:%02u "),
hrw ,
dt.Minute(),
dt.Second() );
Serial.print(datestrings + AMPM );
lcd.print(datestrings + AMPM);
lcd.setCursor(1, 1);
char datestring[11];
snprintf_P(datestring,
countof(datestring),
PSTR("%02u/%02u/%04u "),
dt.Month(),
dt.Day(),
dt.Year()
);
Serial.print(datestring);
lcd.print(datestring);
}