ESP32 Firmware Debugging Guide When to Use This Skill Apply this skill when the user: Encounters compilation errors in ESP-IDF projects Sees runtime panics or "Guru Meditation Error" messages Has memory-related crashes or stack overflows Experiences I2C/SPI/UART communication failures Needs help interpreting serial monitor output Debugging Techniques 1. Compilation Error Analysis Missing Includes fatal error: driver/gpio.h: No such file or directory Fix: Check CMakeLists.txt and add the component to REQUIRES: idf_component_register ( SRCS "main.c" REQUIRES driver ) Undefined References undefined reference to 'some_function' Fix: Ensure the component containing the function is in REQUIRES or PRIV_REQUIRES. Type Errors Look for mismatched types between function declarations and implementations. 2. Runtime Panic Analysis Guru Meditation Error Patterns Error Cause Fix StoreProhibited Writing to invalid memory Check pointer initialization LoadProhibited Reading from invalid memory Check null pointers InstrFetchProhibited Corrupted function pointer Check callback assignments IntegerDivideByZero Division by zero Add zero checks Stack Overflow Guru Meditation Error: Core 0 panic'ed (Stack overflow) Fix: Increase stack size in task creation: xTaskCreatePinnedToCore ( task_fn , "name" , 4096 , NULL , 5 , NULL , 0 ) ; // ^^^^ increase this Stack Smashing Stack smashing detected Fix: Local buffer overflow - check array bounds and string operations. 3. Memory Debugging Check Heap Usage ESP_LOGI ( TAG , "Free heap: %lu" , esp_get_free_heap_size ( ) ) ; ESP_LOGI ( TAG , "Min free heap: %lu" , esp_get_minimum_free_heap_size ( ) ) ; Common Memory Issues Memory leak: Missing free() after malloc() Double free: Freeing same memory twice Use after free: Accessing freed memory 4. Communication Debugging I2C Issues E (1234) i2c: i2c_master_cmd_begin(xxx): I2C_NUM error Checklist: Verify I2C address (7-bit vs 8-bit format) Check SDA/SCL GPIO pins Ensure pull-up resistors are present (4.7K typical) Verify clock frequency compatibility Serial/UART Issues Baud rate mismatch TX/RX swapped Missing ground connection 5. Build Commands for Debugging

Clean build to eliminate stale objects

make robocar-clean && make robocar-build-main

Build with verbose output

cd packages/esp32-projects/robocar-main && idf.py build -v

Start serial monitor

make robocar-monitor-main PORT = /dev/cu.usbserial-0001 6. Useful ESP-IDF Config Options Enable in sdkconfig or via idf.py menuconfig : CONFIG_ESP_SYSTEM_PANIC_PRINT_REBOOT - Print panic info before reboot CONFIG_FREERTOS_WATCHPOINT_END_OF_STACK - Detect stack overflow earlier CONFIG_HEAP_POISONING_COMPREHENSIVE - Detect heap corruption Examples Example: Debugging a Stack Overflow User reports: "My ESP32 keeps crashing on startup" Ask for serial monitor output Look for "Stack overflow" in panic message Identify which task is overflowing Suggest increasing stack size from 2048 to 4096 Explain FreeRTOS stack sizing considerations Example: I2C Communication Failure User reports: "I2C device not responding" Verify address with I2C scanner Check GPIO configuration Verify pull-up resistors Check bus speed compatibility Suggest adding delays between transactions if needed