I tried to use the RTC module with ESP32 and got a little stuck, so I wrote about it. To conclude, I solved the problem by bringing #include DS1307RTC.h to the top. This is the ESP32 version of the ReadTest sample code.
The libraries and equipment used are as follows.
DS1307RTC library github.com/PaulStoffregen/DS1307RTC
HiLetgo 3個セット DS3231 AT24C32 時計モジュール リアル時間時計モジュール IICモジュール RTCモジュール Arduinoに対応 並行輸入品
wiring diagram
