SonosESP

Install ​

Flashing takes about a minute. You need a USB-C cable that carries data, and Chrome, Edge or Opera on a desktop — those are the browsers that support Web Serial. Firefox and Safari cannot flash.

If nothing appears when you connect ​

Try the other USB-C port. The board has two and only one of them talks to a computer. This is the single most common reason a board does not show up.

Hold BOOT while connecting. Hold the BOOT button down, plug the cable in while still holding, then release after a couple of seconds. That forces the board into its flashing mode.

Still stuck? See Troubleshooting.

After it finishes ​

  1. Unplug and replug the board
  2. The Wi-Fi setup screen appears
  3. Pick your network and enter the password on the on-screen keyboard
  4. Go to Settings → Speakers → Scan to find your Sonos

Wi-Fi is 2.4 GHz only. If your router uses one name for both 2.4 and 5 GHz, that is a common reason setup fails.

Your settings live in flash and survive both reboots and firmware updates, so you only do this once.

Flashing manually ​

The browser installer is the supported route. These are for when it is not an option — no Chromium browser, a locked-down machine, or scripting a batch of panels.

Grab bootloader.bin, partitions.bin, boot_app0.bin and the firmware for your panel (firmware-4inch.bin or firmware-7inch.bin) from the latest release.

bash
pip install esptool

esptool.py --chip esp32p4 --port COM9 write_flash   0x2000  bootloader.bin   0x8000  partitions.bin   0xe000  boot_app0.bin   0x10000 firmware-4inch.bin

Do not skip boot_app0.bin

The part at 0xe000 resets the OTA data. Without it, a panel that has already taken an over-the-air update keeps booting the OTA slot — so the flash appears to succeed and the old firmware still runs.

Replace the port with yours: COM9 on Windows, /dev/ttyUSB0 or /dev/cu.usbserial-* on Linux and macOS. On Linux, add yourself to dialout (sudo usermod -a -G dialout ) and log back in if you get a permission error. If flashing keeps failing, esptool.py --chip esp32p4 --port COM9 erase_flash first — that also wipes your Wi-Fi credentials and settings.

From a clone, PlatformIO does the same thing in one step:

bash
pio run -e esp32_4inch --target upload    # or -e esp32_7inch

Updating later ​

You do not need the browser again. The panel updates itself from Settings → Firmware Update. See Updating.