WeMOS Mega + WiFi R3 ATmega2560 + ESP8266 USB-TTL For Arduino Mega NodeMCU Features: Full integration on one board: Mega R3 ATmega2560 and WiFi ESP8266 with memory 32Mb (megabyte) All of the modules can work together or each separately. And everyone has their own pinout headers The convenient solution for the development of new projects requiring Uno and WiFi Via USB you can update sketches and firmvare for ATmega2560 and for ESP8266. For this on board have the USB-serial converter CH340G Use this board is very simple The board has DIP-switch, to connect the modules For example, to: USB and ATmeg2560, USB and ESP8266, ATmega2560 and ESP8266 Table DIP- Switch: Connection DIP 1 2 3 4 5 6 7 ATmega2560<->ESP8266 ON ON OFF OFF OFF OFF OFF USB <->ATmega2560 OFF OFF ON ON OFF OFF OFF USB<->ESP8266 (Update firmware or sketch) OFF OFF OFF OFF ON ON ON USB<->ESP8266 (communication) OFF OFF OFF OFF ON ON OFF All independent OFF OFF OFF OFF OFF OFF OFF Special solution: USB <->ATmega328<-> ESP8266 DIP SWITH 2 Connection 1 2 3 4 5 6 7 USB <-> ATmega2560<-> ESP8266 ON ON ON ON OFF OFF OFF To RXD3/TXD3 USB converter CH340G connect to RX0/TX0 of ATmega2560 ESP8266 connect to RX3/TX3 of ATmega2560 Size: 10.5x5.3cm/4.13x2.09inch Quantity: 1 Pc Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 1 Pc x Mega + WiFi Board