Hi, I need to store some variables and retrieve them also when power goes down: may I do this in an ESP8266 (and in ESP32) at runtime? Without an external flash card I mean.
You can use the EEPROM library to save variables permanently.
Then, at the beginning of you code read the variables saved on the EEPROM.
Learn more here: https://arduino-esp8266.readthedocs.io/en/latest/libraries.html#eeprom
We have a tutorial about that with the ESP32: https://randomnerdtutorials.com/esp32-flash-memory/
I hope this helps.
I need it in uPython but following your hint I found this: https://github.com/dda/MicroPython/blob/master/EEPROM.py.
I’ll give it a try and let you know if it works. In the meanwhile if you know other uPython libs to read/write ESP 82266 EEPROM please let me know.
Have a nice day.
That library seems to be used with external EEPROM modules. I’m not sure if it works with the internal ESP32 flash memory.
Alternatively, you can create a file, write to the file, and then read the file if needed. See here: http://docs.micropython.org/en/latest/esp8266/tutorial/filesystem.html
of course! Silly question! I didn’t think about this way.
Thanks a lot!