Jan 242013
I got my arduino for a few days now and here comes my first adventure :
use an arduino + a lcd + a RTC to display a clock.
First lets go with the wiring :
Then the code :
// ds1302 library can be found here : http://www.henningkarlsen.com/electronics // // DS1302: RST / CE pin - Arduino Digital 12 // I/O / DAT pin - Arduino Digital 11 // SCLK pin - Arduino Digital 10 // LCD: DB7 - Arduino Digital 7 // DB6 - Arduino Digital 6 // DB5 - Arduino Digital 5 // DB4 - Arduino Digital 4 // RS - Arduino Digital 8 // E - Arduino Digital 9 // RW to ground? //seems it is better to NOT plug VCC when setting the clock... #include#include // Init the DS1302 //DS1302(ce, data, clock); DS1302 rtc(12,11,10); // Init the LCD LiquidCrystal lcd( 8, 9, 4, 5, 6, 7 ); void set_time() { rtc.setDOW(SUNDAY); // Set Day-of-Week to FRIDAY rtc.setTime(19, 2, 0); // Set the time to 12:00:00 (24hr format) rtc.setDate(13, 1, 2013); // Set the date to August 6th, 2010 } void setup() { Serial.begin(9600); // Set the clock to run-mode, and disable the write protection rtc.halt(false); rtc.writeProtect(false); // Setup LCD to 16x2 characters lcd.begin(16, 2); // The following lines can be commented out to use the values already stored in the DS1302 //set_time(); } void loop() { // Display time centered on the upper line lcd.setCursor(4, 0); lcd.print(rtc.getTimeStr()); // Display abbreviated Day-of-Week in the lower left corner lcd.setCursor(0, 1); lcd.print(rtc.getDOWStr(FORMAT_SHORT)); // Display date in the lower right corner lcd.setCursor(6, 1); lcd.print(rtc.getDateStr()); Serial.print(rtc.getTimeStr()); Serial.print(" "); Serial.print(rtc.getDOWStr(FORMAT_SHORT)); Serial.print(" "); Serial.println(rtc.getDateStr()); // Wait one second before repeating :) delay (1000); }
And finally a nice picture to illustrate it :
Hope you’ll enjoy it as much as I did 🙂
/Erwan
hi, if i only need the second to display on lcd,how to write the code?
I found that « lcd.print(second) » cant work.
suggestion : put the result of rtc.getTimeStr() in a string and parse it ?