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Project — 2018

Temperature Display

A hardware project that reads ambient temperature and humidity from a DHT11 sensor and displays the data on a 16x2 LCD — powered by Arduino.

ArduinoIoTHardware
Arduino temperature display with LCD showing readings

The assembled circuit — DHT11 sensor feeding live readings to a 16x2 character LCD.

Overview

Atoms meet bits

This project bridges the physical and digital worlds. A DHT11 temperature and humidity sensor continuously samples the environment, sending digital readings to an Arduino microcontroller. The Arduino processes this data and renders it on a 16x2 character LCD in real-time — a self-contained weather station on a breadboard.

The 16x2 LCD provides a clear, always-on display showing both temperature (in Celsius) and relative humidity percentage. The system updates continuously, reflecting environmental changes as they happen.

Controller

Arduino

Sensor

DHT11

Display

16x2 LCD

Language

C / Arduino

Domain

IoT / Hardware

Update Rate

Real-time

Architecture

Simple, elegant circuit design

┌──────────┐ ┌─────────────────┐ ┌──────────┐ │ DHT11 │ │ Arduino │ │ 16x2 LCD │ │ Sensor │──data──│ Microcontroller│──data──│ Display │ │ │ │ │ │ │ │ Temp + │ │ • Read sensor │ │ Line 1: │ │ Humidity │ │ • Format data │ │ Temp °C │ │ │ │ • Drive LCD │ │ Line 2: │ └──────────┘ └─────────────────┘ │ Humid % │ └──────────┘ VCC ────────── 5V ──────────────────── VCC GND ────────── GND ─────────────────── GND

Technical

Reading the physical world

The DHT11 communicates via a single-wire digital protocol. The Arduino sends a start signal, then reads 40 bits of data: 16 bits for humidity, 16 bits for temperature, and 8 bits for a checksum. The timing of high/low signals encodes binary ones and zeros — a protocol that requires precise microsecond-level timing in the firmware.

The LCD is driven via the LiquidCrystal library, using 4-bit parallel mode to minimize pin usage. Custom formatting ensures the readings are clearly labeled and easy to read at a glance from across a room.