Build an Arduino-based humidity and temperature meter in just one day and for just $10. This design uses the Si7021 humidity and temperature sensor, a 128x64 OLED display and a clone Arduino Uno.
PLEASE NOTE: Adding the level shifter board is COMPLETELY UNNECESSARY as the little GY21 PCB already has these components onboard. My bad :(
[ Ссылка ]
![](https://s2.save4k.ru/pic/C1qTztVkDa4/maxresdefault.jpg)