Installation and flashing

You can flash rdzTTGOsonde via the browser-based web flash tool, the esptool.py command‑line utility, or Espressif’s Windows Flash Download Tool.

Option 1 – Flash from your browser (recommended)

When using a supported browser (Chrome/Edge/Opera), the ESP32 web flash tool can program the TTGO board directly from this page.

Browser‑based flash tool

If your browser does not support WebSerial, you can use the command‑line or Windows GUI options below.

Option 2 – Command‑line (esptool)

For first time installation, if you prefer the CLI.

Full image flashing

Flashing a full image writes the application, the fonts, and the internal filesystem. This overwrites all configuration stored in flash.

esptool --chip esp32 --baud 921600 \
  --before default_reset --after hard_reset write_flash -z \
  --flash_mode dio --flash_freq 80m --flash_size detect \
  0x1000 <filename.bin>

The important part is the start offset 0x1000 for the full image.
Replace <filename.bin> with the downloaded firmware image.
Add --port <port> to select a specific device (e.g. COM1: on Windows or /dev/cu.SLAB_USBtoUART on macOS).

Updating code only (update.bin)

If you only want to update the application code and keep your existing internal file system contents, flash update.bin at 0x10000:

esptool --chip esp32 --port /dev/cu.SLAB_USBtoUART --baud 921600 \
  --before default_reset --after hard_reset write_flash -z \
  --flash_mode dio --flash_freq 80m --flash_size detect \
  0x10000 update.bin

This only updates the firmware; the internal file system is left unchanged. OTA does more: it applies the same code update and then selectively updates some files in the internal file system while keeping your config — prefer OTA when the device is on the network. Layout changes in newer versions may not apply with code-only flashing; see the versioning notes on the Downloads page.

Option 3 – Windows GUI (esptool)

For users who prefer a graphical tool on Windows, Espressif provides a Flash Download Tool. The UI is older, but the correct offsets are crucial.

Flash Download Tool

Use the screenshot as a reference for the correct offset fields.

You can download the GUI tool from Espressif: Flash Download Tools (Espressif).

Select your binary file, then set the same offsets as in the esptool.py example above (for example 0x1000 for full images, 0x10000 for update.bin).

Example configuration of the Espressif Flash Download Tool with correct offset fields

After flashing

First boot, Wi‑Fi setup, and accessing the web UI.

First boot

Power up and wait for the device to start.

Disconnect and reconnect power after flashing completes.
Wait for the device to create its Wi‑Fi AP or join your WLAN.

Accessing the web UI

Use your browser to reach the device.

Connect to the device’s AP or your configured network.
Open the status page in your browser (for example: http://rdzsonde.local/, depending on your setup).
Use the web UI to configure channels, Wi‑Fi, and other options.