Please refer the models shown below for instructions.

Serial Communication
Interfacing of Keypad
Led control Using Bluetooth
7 Segment Counter Display
Home Security using PIR Sensor
Currency Counter
Smart Irrigation
Temperature Display on LCD
Smoke Detector
ADC Interfacing
RADAR
Interrupt Interfacing
Led Fading
Interfacing of Ultrasonic Sensor
Interfacing of MQ-4
Interfacing of MQ-3
Interfacing of Color Sensor
Interfacing of GSM module