This paper presents a compact embedded vibration-monitoring platform that combines real-time spectral indication with triggered acquisition of raw tri-axial acceleration. The hardware comprises an Arduino Due microcontroller, an MPU6050 microelectromechanical-system accelerometer, a 128 × 64 organic light-emitting-diode display, and microSD storage. In the onlineanalysis state, the system samples at 400 samples/s and updates a local spectrum using 64-point Hann-windowed fast Fourier transforms. When the pulse-width-modulated trigger exceeds the prescribed threshold, the firmware enters a recording state in which display refresh and spectral processing are suspended, and the three signed 16-bit acceleration channels are stored in 256-sample binary blocks for 20 s. The resulting record contains 8000 samples, yielding nominal frequency spacings of 6.25 Hz for the online display and 0.05 Hz for full-record post-processing. The available motor test indicates a dominant spectral component at 39.5 Hz and a vibration-velocity root-mean-square value of 3.46 mm/s. The zone-C indication shown in the original MATLAB output is interpreted only within the threshold scheme implemented in the prototype and is not presented as formal ISO 20816-3 compliance because the required machine classification, mounting, measurement-bandwidth, and calibration data were not fully documented. Analytical calculations and controlled numerical evaluations confirm the buffer timing, storage demand, frequency resolution, and behavior of the 10 Hz high-pass operation. The proposed platform is therefore suitable for laboratory instruction, preliminary condition screening, and acquisition of records for subsequent analysis, while calibrated instrumentation and machine-specific validation remain necessary for safety-critical deployment.