The Arduino Core for ESP8266 and ESP32 uses one SPI flash memory sector to emulate an EEPROM. When you initialize the EEPROM object (calling begin) it reads the contents of the sector into a memory buffer. Reading a writing is done over that in-memory buffer. Whenever you call commit it write the contents back to the flash sector. Due to the nature of this flash memory (NOR) a full sector erase must be done prior to write any new data....
For months I've been searching for a settings manager for my Arduino and ESP8266 projects. There are basically two issues to take care of: On memory settings or** how do you access to the configuration values** from your code Persistence or how do you store the configuration across reboots For the first issue common solutions in high level languages are key-value solutions in the form of containers or hash arrays....
My MQTT network at home moves up and down a lot of messages: sensor values, triggers, notifications, device statuses,… I use Node-RED to forward the important ones to PushOver and some others to a Blynk application. But I also happen to have an LED display at home and that means FUN. LED displays are cool. Your team's score, your number in the IRS queue, the estimated arrival time for your next commute,… Now that TVs are replacing LED displays (like the later did with the electromechanical ones) they have acquire an almost vintage-status....
Some 3 years ago I started building my own wireless sensor network at home. The technology I used at the moment has proven to be the right choice, mostly because it is flexible and modular. MQTT is the keystone of the network. The publisher-subscriber pattern gives the flexibility to work on small, replaceable, simple components that can be attached or detached from the network at any moment. Over this time is has gone through some changes, like switching from a series of python daemons to Node-RED to manage persistence, notifications and reporting to several “cloud” services....
