Flashing the ESP32 device
Connect your ESP32-S3 device to a USB port on your PC.
Download firmware.zip from https://github.com/ClassicDIY/SkyeTracker/releases and extract the content into a folder.
To flash your ESP32‑S3 device using the command below:
python -m esptool write_flash -z --flash_mode qio --verify 0x0 .\bootloader.bin 0x8000 .\partitions.bin 0x10000 .\firmware.bin
…your Windows PC must meet the following requirements.
The flashing command uses:
python -m esptool
So Python must be installed and available in your system PATH.
Open Command Prompt and run:
python --version
If you see a version number, Python is installed.
Download it from:
https://www.python.org/downloads/windows/
During installation, ensure you check:
☑ Add Python to PATH
esptool is the utility that communicates with the ESP32‑S3 bootloader.
Install it using pip:
pip install esptool
python -m esptool version
If it prints a version number, esptool is installed correctly.
Most ESP32‑S3 boards work on Windows 10/11 without drivers.
If the device does not appear as a COM port, install:
Espressif USB JTAG/CDC Driver
https://www.espressif.com/en/support/download/other-tools
Your ESP32‑S3 must show up in Windows as a COM port.
Open:
Device Manager → Ports (COM & LPT)
Look for something like:
USB Serial Device (COM30)USB JTAG/CDC (COM7)Silicon Labs CP210x (COM5)
You must run the command from the folder containing the .bin files.
- Right‑click inside the folder → Open in Terminal
or - Shift + Right‑click → Open PowerShell window here
Some USB‑C and micro‑USB cables are charge‑only.
If the device does not appear as a COM port:
- Try a different cable
- Preferably one known to support data transfer
Most ESP32‑S3 boards enter bootloader mode automatically.
If yours does not:
- Hold BOOT
- Press RESET
- Release BOOT
| Requirement | Why it matters |
|---|---|
| Python installed | Needed to run esptool |
| esptool installed | Provides flashing commands |
| USB drivers installed | Allows Windows to detect the device |
| COM port visible | Required for communication |
| Three .bin files present | Bootloader, partitions, firmware |
| Terminal opened in correct folder | Ensures file paths work |
| Data‑capable USB cable | Ensures reliable flashing |
| Bootloader mode (if needed) | Allows esptool to connect |