Wemos D1 mini, SDS1306, BME280 - connection schema

ESP8266 and SMOG part two: OLED display, measuring conditions

Last time we build a simple SMOG sensor, it’s time to add display (OLED) and to verify the SMOG measurements – the environmental sensor – as we know that humidity over 70% can add up to the SMOG.

What will you need?



  • ESP Easy – already installed in previous step on the ESP8266 which is needed to control our SDS011 sensor

Let’s do it!

This is the hard part – we need to hook up all together, and there’re are several ways to do it , let’s try the KISS approach again: jumper cables:

  • four connectors to VCC of 3,3V – red cable,
  • four GND connectors – blue cable,
  • three connectors for the I2C bus – SCL – yellow cable,
  • three connectors for the I2C bus – SDA – green cable,

Now pay close attention – connect according to this schema:

Wemos D1 mini, SDS1306, BME280 - connection schema
Wemos D1 mini, SDS1306, BME280 – connection schema

In the end you should get a similar “monster”:

Smog Sensor+
Smog Sensor+ – jumper wires are the key

Next-up in our programme – couple of ESPEasy reconfigurations:

  • the names of the sensors and the values – need cleaning up
  • let’s set quick refresh times
  • finally – we need the OLED display to shine – with all the values

The Devices will look like this:

Czujnik Smogu+ - konfiguracja urządzeń
Smog Sensor+ – configuration of the Devices

First name the SDS Sensor (Name): surprise: SDS011, also the PM25 and PM10. Proper names are important for keeping it manageable:

Czujnik Smogu+ - konfiguracja SDS011
Smog Sensor+ – SDS011

Turn to BME280 (coul be also BMP280, if you don’t need the pressure). The Altitude is to be set so we can get proper values of atmospheric pressure:

Czujnik Smogu+ - konfiguracja BME280
Smog Sensor+ – BME280 configuration

And the last step – OLED display configuration:

Czujnik Smogu+ - konfiguracja wyświetlacza SDS011
Smog Sensor+ – SSD1306 configuration

That’s it! Check out how fast the readings change. Go ahead show it in your school/work.

Pomiary smogu
Pomiary smogu