Embedded system composed of two Arduino UNO microcontrollers that communicate through a master-slave architecture via serial communication. The system acts as an automated smart distance reader, utilizing an ultrasonic sensor to monitor distances, processing the logic on a Master node, and transmitting specific actions, system states, and telemetry data to a Slave node for physical user feedback.
- Master-Slave Serial Network: High-fidelity serial communication to synchronize data streams between isolated microcontrollers.
- Ultrasonic Distance Tracking: Accurate, real-time spatial awareness powered by the HC-SR04 sensor connected to the Master node.
- Multilevel Visual Signaling: A dynamic 3-LED status system (Blue, Yellow, Red) driven by the Slave node representing safe, warning, and critical proximity zones.
- Intelligent Telemetry Dashboard: A liquid-crystal display (16x2 LCD) on the Slave end presenting contextual user text based on real-time distance data.
- Brightness/Contrast Control: Integrated analog potentiometer dedicated to physically tuning the display contrast and text legibility.
- 2x Microcontrollers: Arduino UNO R3 (1x Master, 1x Slave).
- 1x Ultrasonic Sensor: HC-SR04 (Distance detection module).
- 1x LCD Display: 16x2 Liquid Crystal Display (Output character monitor).
- 1x Potentiometer: Used for fine-tuning the contrast and visibility of the LCD screen.
- 3x LEDs: Diagnostic indicators (1x Blue, 1x Yellow, 1x Red).
- 3x Resistors: 220 Ω resistors for current-limiting LED protection.
- 2x Protoboards: For component placement and power rail distribution.
- 32x Jumper Wires: M-M / M-F serial interconnects.
- Arduino IDE: Used for developing and compiling embedded C++ code for both independent firmwares.
- Proteus / TinkerCAD: Used for schematic capture, circuit design, and simulation validation.
- GitHub: Repository hosting and code versioning.
The master node processes sensor loops and converts threshold rules into structural packet payloads transmitted through hardware serial ports (TX/RX).
- Master TX (Pin 1) ➡️ Slave RX (Pin 0)
- Common Ground: Both Arduinos share a common
GNDrail to synchronize logic voltage reference levels.
- HC-SR04 (Master):
Triggermapped to Digital Pin 7;Echomapped to Digital Pin 6. - LED Status Matrix (Slave): Blue (Safe), Yellow (Warning), and Red (Critical Danger) connected to designated digital outputs with 220 Ω resistors.
- LCD Display (Slave): Wired using standard parallel interface pins (
RS,E,D4,D5,D6,D7) to monitor incoming buffer text. - Potentiometer (Slave): Wired to the contrast control pin (
V0) of the LCD display to adjust character visibility.
- Hardware Assembly: Assemble the circuit components onto your protoboards following the system schematic layout (
images/esquema-arduino.png) or use the online TinkerCAD Simulation. Ensure both Arduino boards share a single unified Ground (GND). - Flash the Master Firmware: Open the Master node source code in the Arduino IDE and upload it to the designated transmitting Arduino.
- Flash the Slave Firmware: Disconnect the
RX/TXcross-wires temporarily, open the Slave node source code, and upload it to the receiving Arduino. - Initialize System: Reconnect the serial communication data lines (
TXtoRX), power up both microcontrollers via USB or an external DC source, and observe real-time distance calculations and status feedback.
Developed as a practical laboratory application for Embedded Systems engineering.