ESP-IDF Flash

Flash firmware to ESP32 using ESP-IDF tools.

Flash Size and Partition Tables

Flash size defaults to 4MB. Use CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y in sdkconfig.defaults and --flash_size 4MB with esptool. Only use a different size when the actual flash is known (e.g. esptool.py flash_id or from the datasheet).

Partition tables must fit within the flash size. The test firmware provides two layouts:

Set the partition table in sdkconfig.defaults:

CONFIG_PARTITION_TABLE_CUSTOM=y
CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions-4mb.csv"

Local Flash (USB)

source /opt/esp-idf/export.sh
idf.py -p /dev/ttyUSB0 flash           # Flash to specific port
idf.py -p /dev/ttyUSB0 monitor         # Open serial monitor
idf.py -p /dev/ttyUSB0 flash monitor   # Flash and monitor

Remote Flash (RFC2217)

For flashing via RFC2217 serial over network, use the esp32-workbench-serial-flashing skill which has detailed RFC2217 instructions, device discovery, and troubleshooting.

Quick reference (check http://192.168.0.87:8080 for current slot-to-port assignments):

export ESPPORT='rfc2217://192.168.0.87:4001?ign_set_control'
source /opt/esp-idf/export.sh
idf.py flash monitor

Build Commands

source /opt/esp-idf/export.sh
idf.py build                           # Build only
idf.py flash                           # Build (if needed) and flash
idf.py fullclean                       # Clean build directory

Boot Mode

To put ESP32 in bootloader mode:

1. Hold BOOT button
2. Press RESET button
3. Release RESET, then BOOT

Monitor Shortcuts

• Ctrl+] - Exit monitor
• Ctrl+T Ctrl+H - Show help
• Ctrl+T Ctrl+R - Reset target

Troubleshooting