Read a PS2 joystick with Arduino Uno: five-wire connections, centre calibration, a dead band, button debounce and complete serial-monitor code.

Connect an HC-SR501 PIR sensor to Arduino Uno with three wires. Learn startup timing, output hold behaviour and complete motion-input code.

Measure distance with HC-SR04 and Arduino Uno using four-wire connections, complete code, timeout handling and a stable near-object LED indicator.

Build an Arduino light indicator with an analog LDR module. Learn three-wire connections, bright/dark calibration and stable LED switching with complete code.

Learn ESP32 I2C display wiring, address checks and text-and-bar graphics with complete code for a confirmed SSD1306 OLED module.

Build an Arduino push-button counter with contact-pair checks, clear circuit and breadboard diagrams, complete debounce code and troubleshooting.

Build a DHT11 room monitor with Arduino Uno, clear wiring diagrams, complete code, library setup and fixes for failed readings.

Read a TTP223 touch sensor with Arduino Uno using three wires, complete code, connection diagrams and troubleshooting for output modes.

Build a two-resistor voltage divider, read it on Arduino Uno A0 and understand the effects of resistor tolerance and ADC reference voltage.