ESPHome · Salt monitor

Install SaltWatch

Flash the M5Stack ATOM Lite over USB, then enter Wi-Fi credentials in the same browser flow. No local ESPHome installation is needed for the first flash.

M5Stack ATOM Lite C008 · ESP32

Before you connect

  1. Use desktop Chrome or Microsoft Edge and a data-capable USB cable. The ATOM Lite end must be USB-C; use USB-C or USB-A at the computer end.
  2. Close ESPHome, serial monitors, and any other program using the device's serial port.
  3. Connect the ATOM Lite directly to the computer. The C008 automatically enters download/programming mode over USB; no button combination is normally required.
  4. Click install, select the port named M5Stack, USB Serial, or similar, and approve erasing the device.
  5. When prompted, enter the 2.4 GHz Wi-Fi network and password.
This browser cannot use Web Serial. Open this page in desktop Chrome or Microsoft Edge. Web Serial access is blocked. Reload this HTTPS page and allow serial access.
Security and additional help

Local-network access

The web interface and both firmware update methods intentionally have no password. Anyone who can reach SaltWatch can change its controls or replace its firmware. Keep it on a trusted network and never expose it to the internet.

ESP Web Tools provides connection help when no serial port is selected. For ATOM Lite-specific guidance, see the installation guide.