Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By tceel
#58521 Hello friends.
I have a question about ESP's EEPROM.I want to know when i accomplish EEPROM.write() command ,where is my data stored? inside ESP8266 or inside 25Q40BT ?
If it stored inside 25Q's why I can only save 4KB data?
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By rudy
#58522 I don't know the answer to that. But eeprom is not the only option for storing data. SPIFFS and the file system might be the answer for you. There really is no eeprom with the ESPs. Just flash made to seem like eeprom.
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By martinayotte
#58530 The data written in EEPROM are stored/cached in RAM until EEPROM.commit() occurs.
The 4096 number comes from the fact that Flash sector size is 4096. And it is also the space reserved between SPIFFS and the WiFi setting. I don't think it is a limitation by itself, although I didn't tried, I think it could be larger if LD scripts and cores files are modified accordingly. But is there any needs to do so, since EEPROM is only an emulation while we can still use storage with ESP.flashWrite() and ESP.flashRead() directly without such limitation.