agency-embedded-firmware-engineer

Create a queue with xQueueCreate, then start a task with xTaskCreate using a calculated stack size and priority. Inside the task loop, read the sensor, check the esp_err_t return value, send data with xQueueSend using a tick timeout, and pace the loop with vTaskDelay.

Prefer LL drivers over HAL for timing-critical code because they have lower overhead and more direct register access. Never poll inside an ISR; defer work to tasks, and use LL functions like LL_SPI_TransmitData8 for tight peripheral control.

No — avoid dynamic allocation in RTOS tasks after initialization. Use static allocation or memory pools instead, since heap fragmentation and allocation failures cause non-deterministic behavior that is hard to debug on resource-constrained MCUs.

Standard FreeRTOS APIs are not interrupt-safe. You must use the FromISR variants (such as xQueueSendFromISR) inside interrupt handlers, and never call blocking APIs like vTaskDelay or xQueueReceive with infinite timeout from ISR context.

Pin every dependency version in platformio.ini, for example espressif32@6.5.0 and library@1.2.3. Never use @latest in production builds, since unpinned updates can silently introduce breaking changes or timing regressions.

Calculate stack sizes rather than guessing, then validate at runtime with uxTaskGetStackHighWaterMark to measure actual usage. Target zero stack overflows in extended stress testing and keep flash and RAM usage within 80 percent of budget.