Smart Object Counter System

A simple AVR-based object counter that uses an IR obstacle sensor to detect passing objects, displays the count on a 16x2 I2C LCD, and provides visual feedback via an RGB LED.

See implementation: counter.c (key symbols: F_CPU, IR_SENSOR_PIN, RESET_BUTTON, RED_PIN, GREEN_PIN, BLUE_PIN, set_color, I2C_init, LCD_init, LCD_print, LCD_setCursor, main).

Features / Objectives

• Real-time counting of objects passing an IR sensor.
• Live count displayed on 16x2 I2C LCD.
• RGB LED status: green on detection, blue idle.
• Manual reset button to clear the count.
• Implemented with low-level AVR register programming (no Arduino libraries).

Components

• Arduino Uno (ATmega328P) — controller
• IR-08H obstacle sensor — detection
• KY-016 RGB module — visual status
• 16x2 LCD with I2C backpack — display
• Push button — reset
• Breadboard, jumper wires, 5V supply

Wiring (summary)

• IR OUT -> Arduino D2 (PD2) IR_SENSOR_PIN
• IR VCC -> 5V
• IR GND -> GND
• RGB RED -> D9 (PB1) RED_PIN
• RGB GREEN -> D10 (PB2) GREEN_PIN
• RGB BLUE -> D11 (PB3) BLUE_PIN
• Reset button -> one side to PD3 (D3) RESET_BUTTON, other side to GND (use internal pull-up)
• LCD SDA -> A4, SCL -> A5, VCC -> 5V, GND -> GND

(Refer to counter.c for exact pin macros and behavior.)

Operation

1. On power-up the LCD shows "Object Counter" and initializes peripherals via I2C_init and LCD_init.
2. The program polls the IR sensor on IR_SENSOR_PIN. A LOW on this pin indicates an object and increments the count (debounced via software).
3. On detection the LED is set via set_color to green and the new count is printed using LCD_print/LCD_setCursor.
4. When idle the LED displays blue. Pressing the reset button (active LOW) clears the count.