Design of a MEMS DMD micro projection control system based on STM32 and FreeRTOS

Abstract This study presents a hardware-software co-designed control system for Digital Micromirror Device (DMD), specifically tailored for moderate-speed micro-projection applications where conventional FPGA-based solutions are often prohibitively expensive and overly complex. The proposed architecture adopts a collaborative dual-microcontroller approach, comprising an STM32H743 as the master controller and an STM32F103 as the coprocessor, orchestrated by the FreeRTOS real-time operating system to ensure deterministic task scheduling. Key innovations include a reengineered data transmission pathway that leverages the FMC parallel bus and DMA for low-latency, real-time pattern delivery, combined with a high-precision synchronization mechanism to maintain temporal accuracy. Experimental results demonstrate that the system achieves stable binary pattern projection at standard resolutions with individual micromirror addressing, while significantly reducing hardware costs, minimizing PCB footprint, and shortening development time compared to traditional FPGA-based designs. Long-term reliability is validated through extended continuous operation tests, confirming its robustness and suitability for industrial inspection systems and portable instrumentation. To promote accessibility and further research, the complete hardware schematics and firmware are made openly available.