NodeMCU versi 3. Description: Use CH340G Open-source, Interactive, Programmable, Low cost, Simple, Smart, WI-FI enabled FOR Arduino like hardware IO Advanced API for hardware IO, which can dramatically reduce the redundant work for configuring and manipulating hardware. Code like FOR arduino, but interactively in Lua script. Nodejs style network API Event-driven API for network applicaitons, which faciliates developers writing code running on a 5mm*5mm sized MCU in Nodejs style. Greatly speed up your IOT application developing process. Lowest cost WI-FI