Looking for practical Arduino projects? This guide shows how to control a relay from your smartphone using an Arduino Uno — either via Bluetooth or Wi-Fi.

Circuit Diagram Below is the circuit schema of the car control system, including the Arduino, L298N motor driver, and HC-SR04 ultrasonic sensor. Note: The pin numbers in the diagram may differ from ...

This connects the receive (RX) pin of the HC-05 Bluetooth module to pin 11 on the Arduino. Pin 11 is configured as the TX pin in the software serial port (BTSerial), meaning it will send data to the ...

Connect Rx (pin 2) directly to TXD of the HC-05. Since pin 3 cannot be connected to RXD (as the HC-05 expects 3.3V logic levels), a potential divider with 1k and 2k resistors is used to connect RXD to ...

I am using the l2C Protocol for Communication between the two Arduinos. For Arduino 1 (Master Arduino): The Temperature and Humidity Sensor is connected to pin 9. The Main Gate Servo, Tank Servo and ...