Features : Micro USB-Lowest cost WI-FI: Less than INR 500 WI-FI MCU ESP8266 integrated and esay to prototyping development kit. NodeMCU provide the best platform for IOT application development at the lowest cost. , Arduino-like hardware IO: Advanced API for hardware IO, which can dramatically reduce the redundant work for configuring and manipulating hardware. Code like 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 inNodejs style. Greatly speed up your IOT application developing process.
NodeMCU is an open-source firmware and development kit that helps you to prototype your IOT product within a few Lua script lines. The Development Kit based on ESP8266, integrates GPIO, PWM, IIC, 1-Wire and ADC all in one board. Power your developement in the fastest way combinating with NodeMCU Firmware!
V3 is a "version" Introduced by producer LoLin to signify minor improvements to the V2 boards. Among others they claim their USB port to be more robust which is based on CH-340 chipset.
If you you compare the pin layout there's only a tiny difference to the V2 layout. LoLin use one of the two reserve pins for USB power out and the other for an additional GND.
Watch out though for the difference in size! This LoLin board is significantly larger than the Amica and DOIT V2 boards.
Integrated pcb Antenna and usb port, 4M Flash Memory