newFirmware

Quick reference for backing up the EMO ESP32 flash, extracting the SPIFFS partition, and flashing custom firmware.

These commands assume:

• You are using PowerShell on Windows.
• You replace COMx with the actual ESP32 serial port.
• You run commands from the project root when using .\build\... paths.

Flash Layout Used By This Project

From partitions.csv:

• Full flash size: 0x1000000 (16 MB)
• App slot ota_0: 0x20000
• SPIFFS partition storage: 0xA20000
• SPIFFS size: 0x100000

SPIFFS settings used by this project:

• Block size: 4096
• Page size: 256

Full Backup

Back up the full 16 MB flash. It is a good idea to dump it at least 5 times and compare hashes so you know the backup is stable.

esptool.py --chip esp32 -p COM25 -b 115200 read_flash 0x0 0x1000000 "$env:USERPROFILE\Desktop\esp32_full_16MB.bin"

Full Restore

This rewrites the entire 16 MB flash from a full-chip backup image.

esptool.py --chip esp32 -p COM11 -b 115200 write_flash --flash_mode keep --flash_freq keep --flash_size keep 0x0 "$env:USERPROFILE\Desktop\esp32_full_16MB.bin"

Backup SPIFFS Only

This reads only the storage SPIFFS partition instead of the whole flash.

esptool.py --chip esp32 -p COMx -b 115200 read_flash 0xA20000 0x100000 "$env:USERPROFILE\Desktop\storage.bin"

Extract Files From SPIFFS

spiffsgen.py only creates SPIFFS images. It does not unpack them. To extract files from storage.bin, use mkspiffs with the matching geometry:

mkspiffs -u .\spiffs_extracted -b 4096 -p 256 -s 0x100000 "$env:USERPROFILE\Desktop\storage.bin"

Notes:

• The output folder will be created as .\spiffs_extracted.
• For this firmware image, the extracted files are motion files under mot\.
• If you want to dump the partition directly from the device and then unpack it, run the SPIFFS backup command first, then the mkspiffs command above.

Flash SPIFFS Back To The Device

If you already have a SPIFFS image to write back, flash it at the storage partition offset:

esptool.py --chip esp32 -p COMx -b 115200 write_flash --flash_mode keep --flash_freq keep --flash_size keep 0xA20000 .\build\storage_idf55.bin

Flash Custom Firmware

If you only want to replace the application in ota_0, flash the app binary at 0x20000:

esptool.py --chip esp32 -p COMx -b 115200 write_flash --flash_mode dio --flash_freq 40m --flash_size 16MB 0x20000 .\build\emo_firmware.bin

After base-firmware.bin is flashed, connect to the ESP32 hotspot and set a Wi-Fi network. Once that is done, you can access the web page via node-manager.local.

Install Apps From The UI

To flash apps, open the Apps Manager in the web UI and select the app you want to install.

If the app you are installing is a test app, remember to remove the auto-start check before installing it.

Safety Notes

• Double-check the COM port before writing.
• A full restore overwrites everything, including both app slots and SPIFFS.
• An app-only flash at 0x20000 does not restore SPIFFS contents.
• Keep at least one untouched full 16 MB backup before testing custom builds.