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TrailCurrent circuit board with USB cable and green status LED

Flash Firmware

Program a TrailCurrent module directly from your browser. Pick a module, choose a release, connect over USB—no toolchain, no command line.

1

Choose a Module

Select which TrailCurrent ESP-IDF module you want to flash.

2

Choose a Release

Releases are pulled live from GitHub. Pre-releases are included and marked.

3

Connect & Flash

Plug the module into a USB port, click Connect Device, and select the serial port for your board. Your browser will ask permission.

Not connected
4

Output

Progress, chip detection, and any errors appear here.

Flashing uses esptool-js (Espressif, Apache-2.0).

Troubleshooting

"No compatible devices found"

The browser's serial port dialog is empty even though a device is plugged in.

Linux
  • Snap-installed browsers (Ubuntu default) are sandboxed and cannot access serial ports. Run the following, then restart the browser: 
    sudo snap connect chromium:raw-usb
    Replace chromium with your browser's snap name if different (e.g. google-chrome).
  • User permissions — add yourself to the dialout group, then log out and back in: 
    sudo usermod -a -G dialout $USER
  • If using a Flatpak browser, serial access may not be available. Use a natively-installed browser instead.
macOS
  • macOS requires no extra configuration — Chrome and Edge support Web Serial out of the box.
  • If the device still doesn't appear, you may need to install a USB-serial driver for your chip (CP210x or CH340 — check the board documentation).
Windows
  • Install the USB-serial driver for your board's chip: CP210x (SiLabs) or CH340 (WCH).
  • Verify the device appears in Device Manager under "Ports (COM & LPT)".
All platforms
  • Use Google Chrome, Edge, or Opera. Firefox and Safari do not support Web Serial.
  • Close other serial tools (Arduino IDE, idf.py monitor, PlatformIO, screen, minicom) — only one program can hold a port at a time.
  • Try a different USB cable — some cables are charge-only.

Device not entering flash mode

  • Hold the BOOT button while plugging in the USB cable, or hold BOOT and press RESET while connected.
  • Some ESP32-S3 boards with native USB appear as a different port in bootloader mode — try selecting the other port in the dialog.

"Flash failed: Failed to fetch"

  • This is usually a network or CORS issue downloading firmware from GitHub. Refresh the page and try again.
  • If using a VPN or corporate proxy, try disabling it temporarily.