Simple example code of using HTU21D sensor to read temperature and humidity values and also send those values to thingspeak cloud. This project use micropython v1.17 (2021-09-02) and ttgo t7 v1.3 board powered by 18650 li ion battery. To save battery live I call deep sleep function and wake up board every 30 min. Recommend to desolder LED diodes from board using hot air.
| 1 | ESP32 | HTU21D |
|---|---|---|
| 2 | vcc 3.3 | vcc |
| 3 | gnd | gnd |
| 4 | pin 22 | scl |
| 5 | pin 21 | sda |
- Probably you will need to solder jumper pads on htu21d sensor Type i2c.scan() in repl to discover sensor
- Set wlan.active(False) right before call deep sleep to avoid internal wifi error
- Set machine.idle() while waiting for wifi connection to save battery