Arduino based Temperature and Humidity/Humidex meter with DHT22 sensor and color LCD


This project consist of Arduino board, serial TFT LCD 128×160 display, DHT22 sensor and obviously bread board and jumpwires.

Project features:

TFT serial LCD display (ST7735 controller)

I used 128×160 resolution display from ICStation. It comes as module ready for mounting on a bread board and also have SD card slot.

Connecting the display to Arduino is quite tricky, but there is table for that is you are using Adafruit LCD  and GFX libraries.


LCD module pin Arduino pin Comments
6 (Reset) 8 Changeable via code. (Can be connected to Arduino hardware reset pin or +3,3V)
7 (A0) 9 Changeable via code
8 (SDA) 51 (MOSI) Pin number depends on Arduino board
9 (SCK) 52 (SCK) Pin number depends on Arduino board
10 (CS) 10 Changeable via code
15 (LED+) + 3,3 V
16 (LED-) GND

You may notice that GND and VCC pins on LCD board is not connected, with them connected LCD tends to blink when contents are updated.


Temperature and humidity sensor is connected that way:

DHT22 Arduino pin Comments
1 (VCC) +3,3 V
2 (DATA) 7 Changeable via code

Picture after connections:


Program code:

Program uses DHT22, LCD, GFX libraries from Adafruit. Don’t recommend use any other libraries for DHT22 sensor because it may give not correct reading at the temperatures below zero.

Humidex calculated by method presented there and color representation is from

Project code is hosted on github.

Project demo video: