This repository contains two projects I've developed for the Arduino Uno platform.
- Task - Temperature-Controlled Fan: A solution to a technical challenge involving software-based PWM control.
- Jwalamukhi - Multi-Sensor Alarm: A personal project that uses several sensors to create a home safety alarm system.
This project is a solution to a technical task requiring a fan's speed to be controlled by temperature, using the specific constraint of a non-PWM digital pin.
- Reads temperature from a 10k NTC thermistor on pin
A0. - Controls a DC fan (or an LED for simulation) on digital pin
D13. - Uses a 3-level speed logic (OFF, 50%, 100%).
- Prints the current temperature and fan status to the Serial Monitor.
A key part of this task is the requirement to control the fan speed using only pin D13, which is not a hardware PWM pin on the Arduino Uno.
To solve this, the code implements a software PWM. This technique rapidly turns the pin on and off using precise microsecond delays to simulate a 50% duty cycle, effectively running the fan at half speed without needing built-in PWM hardware.
You can view and run the simulation for this project on Tinkercad:
- Code: The
.inosketch for the Arduino. - Video: A short video showing the project working.
- Photo: An image of the circuit.
"Jwalamukhi" is a personal project I built that acts as a home safety system by monitoring for multiple potential hazards.
- Multiple Sensors: Uses a temperature sensor, a gas/smoke sensor, and a PIR motion sensor all at once.
- Fan Control: A DC fan automatically speeds up as the room gets warmer.
- Alarms: A buzzer and an LED are turned on if the temperature gets too high, if smoke is detected, or if motion is seen.
- Manual Override: A switch is included to turn on the alarm manually.
- LCD Display: Shows the real-time temperature on a 16x2 LCD screen.
You can view and run the simulation for this project on Tinkercad:
- Code: The
.inosketch for the Arduino. - Image: A screenshot or photo of the project.