
// Reference for connecting SPI see https://www.arduino.cc/en/Reference/SPI
// CONNECTIONS:
// DS3234 MISO --> MISO
// DS3234 MOSI --> MOSI
// DS3234 CLK  --> CLK (SCK)
// DS3234 CS (SS) --> 5 (pin used to select the DS3234 on the SPI)
// DS3234 VCC --> 3.3v or 5v
// DS3234 GND --> GND

const uint8_t DS3234_CS_PIN = 5;

#include <SPI.h>
#include <RtcDS3234.h>

RtcDS3234<SPIClass> Rtc(SPI, DS3234_CS_PIN);

void setup () 
{
    Serial.begin(115200);
    while (!Serial);

    Serial.print("compiled: ");
    Serial.print(__DATE__);
    Serial.println(__TIME__);

    SPI.begin();
    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!");

        // following line sets the RTC to the date & time this sketch was compiled
        // it will also reset the valid flag internally unless the Rtc device is
        // having an issue

        Rtc.SetDateTime(compiled);
    }

    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)");
    }

    // never assume the Rtc was last configured by you, so
    // just clear them to your needed state
    Rtc.Enable32kHzPin(false);
    Rtc.SetSquareWavePin(DS3234SquareWavePin_ModeNone); 
}

void loop () 
{
    if (!Rtc.IsDateTimeValid()) 
    {
        // 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!");
    }

    RtcDateTime now = Rtc.GetDateTime();
    printDateTime(now);
    Serial.println();

	RtcTemperature temp = Rtc.GetTemperature();
	temp.Print(Serial);
	// you may also get the temperature as a float and print it
    // Serial.print(temp.AsFloatDegC());
    Serial.println("C");

    delay(10000); // ten seconds
}

#define countof(a) (sizeof(a) / sizeof(a[0]))

void printDateTime(const RtcDateTime& dt)
{
    char datestring[26];

    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);
}

