ATtiny85 Weather Station with SD1331 OLED display
This is a weather station based on an ATtiny85 and an Adafruit Bosch BME280 sensor breakout. It displays the atmospheric temperature, pressure, and humidity on a 96×64 SD1331 colour OLED display. by David Johnson-Davies:
To display the readings the Weather Station uses a low-cost 96×64 OLED display with 64K colours, and an SPI interface. It’s available from a number of suppliers including Adafruit  or Banggood .
The Weather Station is based on a Bosch BME280; it’s is the perfect sensor for a home weather station as it provides temperature, pressure, and humidity in a single device . It’s available on a breakout board from Adafruit , Sparkfun , or Chinese suppliers such as AliExpress and Banggood. Some boards, such as Adafruit’s, support either 5V or 3.3V operation, so check before buying if this is important to you.
The downside with this sensor is that you have to do quite a bit of calculation to get the final readings; it’s not just a case of reading the values from the device via I2C or SPI, as with some other sensors. Both Adafruit and Sparkfun provide a library to interface to the sensor, but unfortunately these don’t seem to work on ATtiny processors, such as the ATtiny85, so I set about writing my own Tiny BME280 library.
ATtiny85 Weather Station with SD1331 OLED display – [Link]