Espressif ESP8266 User Manual

B. The ESP8266 WorldClock
The WorldClock is yet another simple project which you can build with the WeatherStation
hardware - and you already have a demo installed in your Arduino editor. Just go to File >
Examples > ESP8266 Weather Station > WorldClockDemo
The ESP8266 World Clock

Espressif ESP8266 Specifications

General

Digital I/O Pins	17
Analog Input Pins	1
Wi-Fi	802.11 b/g/n
Operating Voltage	3.0V - 3.6V
Clock Speed	80 MHz / 160 MHz
Operating Temperature	-40°C to 125°C
Dimensions	24mm x 14mm
Processor	Tensilica L106 32-bit micro controller