Minimal Arduino library for sunrise and sunset time.
Given some basic data, such as geographic coordinates and a date, an estimate time of apparent sunrise or sunset is returned in minutes elapsed since midnight.
WARNING: This is an unauthorized port of NOAA's Solar Calculator, hence the package will remain unlicensed. Use at your own risk!
- Launch the Arduino IDE and navigate to Sketch → Include Library → Manage Libraries.
- In the library manager, scroll to Dusk2Dawn or enter the name into the search field.
- Click on the library, then click on the Install button.
- Download the ZIP file.
- Launch the Arduino IDE and navigate to Sketch → Include Library → Add .ZIP Library.... From the prompt, select the ZIP just downloaded.
/* Multiple instances can be created. Arguments are longitude, latitude, and
* time zone offset in hours from UTC.
*
* The first two must be in decimal degrees (DD), e.g. 10.001, versus the
* more common degrees, minutes, and seconds format (DMS), e.g. 10° 00′ 3.6″.
* The time zone offset can be expressed in float in the few cases where the
* the zones are offset by 30 or 45 minutes, e.g. "5.75" for Nepal Standard
* Time.
*
* HINT: An easy way to find the longitude and latitude for any location is
* to find the spot in Google Maps, right click the place on the map, and
* select "What's here?". At the bottom, you’ll see a card with the
* coordinates.
*/
Dusk2Dawn losAngeles(34.0522, -118.2437, -8);
Dusk2Dawn antarctica(-77.85, 166.6667, 12);
/* Available methods are sunrise() and sunset(). Arguments are year, month,
* day, and if Daylight Saving Time is in effect.
*/
int laSunrise = losAngeles.sunrise(2017, 12, 31, false);
int laSunset = losAngeles.sunset(2017, 12, 31, false);
int antSunrise = antarctica.sunrise(2017, 6, 30, true);
/* Time is returned in minutes elapsed since midnight. If no sunrises or
* sunsets are expected, a "-1" is returned.
*/
Serial.println(laSunrise); // 418
Serial.println(laSunset); // 1004
Serial.println(antSunrise); // -1
/* A static method converts the returned time to a 24-hour clock format.
* Arguments are a character array and time in minutes.
*/
char time[6];
Dusk2Dawn::min2str(time, laSunrise);
Serial.println(time); // 06:58
/* Alternatively, the array could be initialized with a dummy. This may be
* easier to remember.
*/
char time2[] = "00:00";
Dusk2Dawn::min2str(time2, laSunset);
Serial.println(time2); // 16:53
/* Do some calculations with the minutes, then convert to time.
*/
int laSolarNoon = laSunrise + (laSunset - laSunrise) / 2;
char time3[] = "00:00";
Dusk2Dawn::min2str(time3, laSolarNoon);
Serial.println(time3); // 11:56
/* In case of an error, an error message is given. The static method also
* returns a false boolean value for error handling purposes.
*/
char time4[] = "00:00";
bool response = Dusk2Dawn::min2str(time4, antSunrise);
if (response == false) {
Serial.println(time4); // "ERROR"
Serial.println("Uh oh!");
}- 2019-6-18: Add license warning.
- 2017-2-9: Bug fix.
- 2017-2-3: Released.