Esp8266: Nodemcu Wifi Module User Manual

: Supports UART, SPI, I2C, and I2S communications.

: Tensilica Xtensa 32-bit LX106 RISC running at 80MHz to 160MHz. Memory : Typically 4MB Flash and 64KB to 128KB RAM. ESP8266 NodeMCU WiFi Module User Manual

: 2.4GHz Wi-Fi (802.11 b/g/n) with an integrated PCB antenna. : Supports UART, SPI, I2C, and I2S communications