         state = ~state;
         digitalWrite(LED_BUILTIN, state);
         // Clear alarm state
-        Clock.checkIfAlarm(1);
+        myRTC.checkIfAlarm(1);
     }
+
+    // Loop delay to emulate other running code
     delay(10);
 }
 

#include <DS3231.h>
#include <Wire.h>

// Clock interrupt pin
#define CLINT 2

// Setup clock
DS3231 Clock;

// Interrupt signaling byte
volatile byte tick = 1;

    // Begin I2C communication
    Wire.begin();

    // Setup alarm one to fire every second
    myRTC.turnOffAlarm(1);
    myRTC.setA1Time(0, 0, 0, 0, 0b01111111, false, false, false);
    myRTC.turnOnAlarm(1);
    myRTC.checkIfAlarm(1);

    // attach clock interrupt
    pinMode(CLINT, INPUT_PULLUP);
