The Pico RTC DS3231 is a real time clock with a DS3231 chip using the I2C bus. It uses an integrated stackable header so you can insert it into the Raspberry Pico and have pins available to attach another HAT board on top. It includes a CR1220 battery to retain the time as there is no inbuilt battery in the Raspberry Pi Pico and if the power is disconnected the inbuilt clock will reset.
DS3231 RTC with Stackable Header
DS3231 Pinout Diagram
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