Espressif ESP8266 User Manual

G. Summary
If everything went well you now have a working ESP8266 WeatherStation. Congratulations!
Let’s look back what we did in this chapter:
⚫ We used the WeatherStation example and created a working copy for us. All changes
will be applied to the copy, not the original example. If you accidentally make your code
unusable you can always go back to the example and start with a fresh copy.
⚫ We installed several libraries by using the Arduino IDE Library Manager. Libraries help us
to reuse code or binaries in many places without using barely maintainable copy/paste
code.
⚫ We created an API key from OpenWeatherMap. Every time we call the
OpenWeatherMap API to update weather data we will send this key along so that
OpenWeatherMap knows who we are. Many service providers use a similar scheme
to control and limit usage of their services.
⚫ We changed a few lines in the code to configure the WiFi settings, update interval, display
pins, timezone and the API key for OpenWeatherMap.
⚫ We connected the OLED display and the ESP8266 and uploaded the firmware.

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