implementing-firmware

Firmware Implementation

Target: $ARGUMENTS

Implement firmware code with mandatory requirement traceability tags, following ESP-IDF or PlatformIO patterns.

References (MUST READ)

Read these before proceeding:

• references/esp-idf-patterns.md — Component structure, FreeRTOS, sdkconfig, idf.py
• references/platformio-patterns.md — platformio.ini, pio commands, library management
• references/c-safety-rules.md — MISRA-C cppcheck flags, clang-tidy, tagging rules

Workflow

1. Detect framework:

   • CMakeLists.txt + sdkconfig* → ESP-IDF
   • platformio.ini → PlatformIO
   • Neither → ask user which framework to use

2. Read existing requirements — Check for docs/requirements.md to understand which SW-REQs need implementing

3. Implement code with mandatory docstrings on every new function:

   /**
    * @brief <What this function does>
    *
    * @requirement SW-REQ-NNN
    * @parent      PRD-REQ-NNN
    * @test        TEST-NNN
    *
    * @param ...
    * @return ...
    */
   

4. Create test stubs in test/ with matching @test TEST-NNN references

5. Lint with cppcheck:

   cppcheck --addon=misra.py --std=c11 --enable=all --xml src/ 2> misra-report.xml
   

6. Build:

   • ESP-IDF: idf.py build
   • PlatformIO: pio run

7. Report — Count tagged functions, list any warnings

Rules

• Every new function must have @requirement, @parent, and @test tags
• Follow existing code style (indentation, naming conventions) in the project
• Use ESP-IDF error handling patterns (ESP_ERROR_CHECK, esp_err_t returns)
• Do not suppress MISRA warnings without documenting the deviation
• Create header declarations alongside implementations
• Test stubs must compile even if test logic is not yet implemented