Active Object

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.

Context Switching in FreeRTOS + QP/C on Cortex-M7: From ISR to Active Object

One line at the end of an ISR wakes an active object in well under a microsecond — or a millisecond later if you leave it out. Here is the full path: hardware exception frame, PendSV, and where QP/C sits in it.