Nrf7002dk and DHT22 sensor Step by step guide

This project reads temperature and humidity from a DHT22 sensor using the nRF7002DK and Zephyr RTOS.The DHT22 is connected to GPIO Port 1, Pin 11, and the data is printed on the serial console.

I built this as my first Hackster.io post because I wanted to start small but make something that works and is useful. Most DHT22 tutorials are for Arduino or ESP32 — I couldn’t find a clean, beginner-friendly guide for nRF7002DK, so I made one.

The way it works is pretty simple:

• The nRF7002DK sends a start signal to the DHT22.
• The sensor sends back pulses encoding humidity and temperature.
• The firmware decodes the pulses, formats the values, and prints them to the console.

That’s it — but this is just the start!The nRF7002DK supports Wi-Fi and Bluetooth, so in future projects I’ll be adding features to send this sensor data wirelessly to the cloud or a mobile app.

DHT22 + nRF7002DK (Zephyr) — Step-by-Step

1) What you’ll need

• nRF7002dk
• DHT22 (AM2302) sensor (module with onboard pull-up preferred)
• Jumper wires
• (If using the raw 4-pin DHT22 sensor) 4.7k–10kΩ pull-up resistor from DATA → 3V3

Power: 3.3 V. Data line is 3.3 V logic (no level shifter needed).

2) Wire it up (as per schematic)

• VCC → 3V3
• GND → GND
• DATA → Port 1, Pin 11 (GPIO P1.11 on nRF7002DK)

If using the raw sensor, add a 4.7k–10kΩ pull-up from DATA to 3V3. Many breakout boards already include this.

3) Code Flashing

• Once everything is ready, clone the repository, build the code, and simply flash it.

4) Output

5) Troubleshooting (quick wins)

• Always reads 0.0 / fails checksum → Check pull-up resistor on DATA; keep wires short (<20–30 cm).
• Random timeouts → Ensure solid 3.3 V power; try a slightly longer k_busy_wait() window (e.g., 40–50 µs sample point).
• No logs → Confirm the correct serial port and 115200 baud; verify CONFIG_UART_CONSOLE=y.