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Mechanical ventilators are of utmost importance in the medical field, being essential for a wide range of applications, from the treatment of acute pulmonary diseases to cardiac surgeries. This study presents the development of a signal acquisition and processing system capable of establishing network communication through the RS485 protocol. The system hardware consists of ESP-WROOM-32U microcontrollers, DS18B20 temperature sensors, MPX5010DP pressure sensors, and MAX485 modules to establish communication, among other necessary components for the device’s operation. The software was developed in C++ and implements features such as a low-pass filter for attenuating noise from the pressure sensor, ensuring greater reliability of the readings. Specific tests were conducted to evaluate the system’s performance for each type of sensor. For the temperature sensor, analyses were performed over 60 s, with and without respiratory cycles, to determine the sensor’s accuracy. Tests with respiratory cycles resulted in a mean µ of 29,99 ◦C, a standard deviation σ of 0,1426 ◦C, and a median of 30,00 ◦C, indicating high precision and reliability of the readings. Pressure sensor tests were conducted in 10 s intervals, adopting a smoothing coefficient α of 0,5501, resulting in a mean absolute error of 6 cmH2O, while maintaining the wave signal characteristics and attenuating reading peaks, demonstrating the effectiveness of the adopted smoothing algorithm. Point-to-point communication tests between the master and slave boards resulted in update frequencies of 8,93 Hz and 3,01 Hz, respectively. These results evidenced the master board’s ability to detect lower amplitude variations in the pressure signal. However, it was observed that the graphs generated by the slave board allowed clear identification of the system’s pressurization and depressurization cycles, as well as the opening and closing of the pressure control valve. The obtained results demonstrated the system’s capability to accurately and reliably monitor pressure and temperature signals, essential parameters in mechanical ventilation systems. The system’s modular design, in terms of both software and hardware, allows for the addition of new sensors, air pressure generation drive systems, as well as wireless communication and the enhancement of control algorithms. In summary, the system has the potential to significantly contribute to addressing the shortage of ventilators during emergency situations, offering a scalable and economical solution in the use of resources.