This is the multi-page printable view of this section. Click here to print...

For suitable output, we recommend to use Google Chrome (15+) or Microsoft Edge (79+).

As of 2025-07-24

How to Initialize ESP32 Firmware

How to restore ESP32 firmware on TWELITE SPOT to the factory default state

This page explains how to restore the product TWELITE SPOT, equipped with the TWELITE wireless module and ESP32, to its factory default state. It does not cover general methods for restoring ESP32 to factory defaults.

If you only want to erase the ESP32 program, you can use the official Espressif web tool (this also applies to TWELITE SPOT).

We apologize to those who arrived here via search engines.

We hope you will remember the ultra-low power wireless module, TWELITE.

This guide shows how to manually restore the firmware written to the ESP32 on TWELITE SPOT to the factory default state using esptool.

Install esptool

esptool is the official utility to write binary files to ESP32.

For detailed installation instructions, please refer to the official guide (English).

Install Python

If Python 3.7 or later is not installed, please install Python 3.7 or later.

https://www.python.org/downloads/

Install esptool itself

Install esptool from PyPI.


pip install esptool

If you do not want to affect your existing Python environment, it is recommended to use pipx.


pipx install esptool

Connect to the host

Connect TWELITE R3 / R2

Connect the TWELITE R3 / R2 to the 7P interface (the side labeled ESP32).

Connect power

Supply 5V power to the USB-C connector on the side.

Always connect the TWELITE R3 / R2 to TWELITE SPOT in the same orientation as shown above. Connecting it in the wrong direction may damage the TWELITE SPOT or TWELITE R3 / R2.

Obtain the binary file

Please download spot-server-2023-05-bin.zip from the link below.

spot-server-2023-05-bin.zip

After downloading, unzip the file.

Start ESP32 in programming mode

Press the ESP32 reset switch EN(RST) and the ESP32 boot switch BOOT on TWELITE SPOT, then release them in the order EN(RST) -> BOOT.

By resetting while pressing BOOT, you can switch ESP32 to programming mode.

Write with esptool

On the terminal where esptool is installed, navigate to the folder where you extracted spot-server-2023-05-bin.zip, and run the following:


esptool --chip esp32 --port {Serial Port} --baud 921600 --before default_reset --after hard_reset write_flash -z --flash_mode qio --flash_freq 80m --flash_size 16MB 0x1000 spot-server.ino.bootloader.bin 0x8000 spot-server.ino.partitions.bin 0xe000 boot_app0.bin 0x10000 spot-server.ino.bin 0x100000 spot-server.littlefs.bin

Replace {Serial Port} with the port name such as COM? or /dev/tty?.

If it fails, please try the following:

Change --flash_mode qio to --flash_mode dio
Change --flash_freq 80m to --flash_freq 40m
Change --baud 921600 to --baud 460800

Reset ESP32

After writing is complete, press and release the ESP32 reset switch EN(RST) on TWELITE SPOT to reset ESP32.

If you do not reset, you cannot exit programming mode.