Thomas

Hello @nopnop2002 Thank you for your cooperation. Can you tell which Arduino core you are using with your STM32F1 board?

Yes. Exact. If using Arduino_STM32 core, it does not make external EEPROM data. However in README.md we recommend using core for STM32GENERIC by Danieleff , installation for IDE Arduino with...

Thank you @nopnop2002 .However, I will include your code and make a bigger library. Finish installing new core, specifically Huaweiwx https://github.com/huaweiwx/STM32GENERIC, this generic core of STM32 for Arduino, have an...