RELIABILITY AND TECHNICAL MAINTENANCE OF MACHINES
DOI:
https://doi.org/10.32718/agroengineering2025.29.122-132Keywords:
AVR ATmega32U4 microcontroller, RTC chip DS1, precision temperature sensor LM35DZ, 8×32 LED matrix display module FC-16, driver chip MAX7219, CAD software Proteus VSMAbstract
The paper presents the design, software implementation, and modeling of a digital clock-thermometer based on the Arduino Micro (ATmega32U4) platform with indication on 4×8×8 (FC-16) LED matrix modules driven by MAX7219 chips. The device provides real-time display of the current date and time (RTC DS1307), temperature in °C/°F (LM35DZ sensor), clock and temperature format settings, text scrolling, and brightness control. The hardware schematic was developed in Proteus VSM, along with algorithms and key software modules (RTC, MAX7219 display, LM35 thermometer). Simulation in Proteus ISIS and testing of a physical prototype confirmed the correct operation of the system. Measurement accuracy, display modes, energy efficiency, EMC aspects, and scalability were analyzed. The digital device is based on the Arduino Micro platform with an AVR ATmega32U4 microcontroller, interfaced with a DS1307 real-time clock, a precision LM35DZ temperature sensor, and an 8×32 FC-16 LED matrix display module consisting of four 8×8 matrices with MAX7219 drivers. The microcontroller reads date and time from the RTC DS1307, the ambient temperature from the LM35DZ sensor, and outputs this information to the LED matrix display. The device supports adjustment of current time, date, and display parameters. The work includes the development of the circuit schematic and the digital clock-thermometer model using Proteus CAD tools. The software and algorithms were implemented in the Arduino IDE. Simulation in Proteus ISIS and prototype testing confirmed system functionality.
The results demonstrate the feasibility of using MAX7219 drivers for matrix display control with minimal I/O lines and highlight the potential of this approach for household and educational measuring devices. Future research should focus on integrating additional sensors (humidity, pressure), implementing wireless time synchronization, and optimizing power consumption.
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