Interrupt Based Update

[desiFish]

Connection of INT Pin of DS3231 to wake up esp32 from deep sleep and update time. Internal RTC-based wakeup works just fine, but with one drawback: ESP32 has no way of knowing if a minute has passed in real-time so it may wake up a bit sooner or later. The time displayed on the Epaper display will always be within a 1-minute range. But with INTERRUPT-based-wake-up, it will always show accurate time.

Resource:
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