A microSD Active Object with QP/C and USDHC1 — and the Card-Detect Line That Lied

Building an SdCard active object on the i.MX RT1062: hardware card detect, the blocking-API problem that forces a worker task, and the coupled CD line that made detection fail unpredictably until I stopped trusting the interrupt.

July 25, 2026 · 11 min · 2189 words · Hoa Nguyen