ESP Easy

ESP Easy is an free and open source MCU firmware for IoT (Internet of Things). and originally developed by the LetsControlIt.com community (formerly known as ESP8266.nu community. It runs on ESP8266 and ESP32 Wi-Fi based MCU (Micro Controller Unit) platforms for IoT (Internet of Things) from Espressif Systems. The name "ESP Easy" by default refers to the firmware rather hardware which uses this firmware. At a low-level the ESP Easy firmware work the same as the NodeMCU firmware which have become popular for commercial usage, it too also creates a very simple operating system on the ESP8266. The main differnce between ESP Easy firmware as NodeMCU firmware is that the former is designed as a high-level toolbox that just work out-of-the-box for pre-defined set of sensors and actuators that users can simply hook-up and read/control over simple web requests without having to write any code at all themselves, including firmware upgrades using OTA (Over The Air) updates.

The ESP Easy firmware can be used to turn ESP modules into an simple multifunction sensor and actuator devices for home automation platforms like Domoticz, OpenHAB, Home Assistant, PiDome, Nodo Telnet, EmonCMS, FHEM, ThingSpeak, and SmartThings (Samsung). Once the firmware is loaded on the hardware will be completely configuration of the ESP Easy is entirely web interface based for all configuration settings. ESP Easy firmware is primary used on ESP8266 modules/hardware as a wireless WiFI sensor device with sensors like temperature, humidity, barometric pressure, LUX, etc., though the ESP Easy firmware also offers some low-level access to actuator functions to control relays.

The firmware is built on the Arduino ESP project which in turn uses many open source projects. Getting started with the ESP Easy takes a few basic steps. In most cases ESP modules comes with the AT firmware or the NodeMCU LUA firmware, and your need to replace the existing firmware with the ESP Easy firmware by flashing the hardware with a (Windows only) flashtool to use it.

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Wikipedia