Compact Arduino Temperature / Humidity Monitor
If you want to make a handy humidity and temperature sensor then this project is for you. This mini Temperature / Humidity Monitor is built based on Arduino (Atmega 328P) and Sensiron SHT11 sensor. To display the result, it is equipped with Adafruit 128×32 OLED. The project uses LEGO shell for housing. The project powered by 2x 3V 2032 cells in series, which are put through a 3.3v regulator to power the board and components.
For power conservation, Dave Astolfo used the sleep abilities of the chip and tied it to Interrupt2 tied to the toggle switch. Pushing the switch ‘in’ would trigger the interrupt and wake the unit. Before it goes to sleep, the power for the OLED and the SHT11 sensor will be shutted down and back on immediately after it wakes. Download source code.