Flexispot E7 ESPHome Integration

ESPHome custom component for controlling and monitoring Flexispot E7 standing desks via Home Assistant.

Features

• Real-time desk height sensor (cm)
• Preset buttons: Sit, Stand, 1, 2
• Manual Up / Down control
• Memory (M) and Wake buttons
• WiFi signal strength sensor
• Encrypted API and OTA password protection

Hardware

• ESP32 development board (e.g. ESP32-DevKitC)
• Flexispot E7 desk
• RJ45 breakout or spliced cable from the desk's control port

Wiring

Connect the ESP32 directly to the desk's RJ45 port (not through the handset):

Wire Color	ESP32 Pin	Function
Green	GPIO1	TX (commands to desk)
White/Blue	GPIO3	RX (data from desk)
Blue	GPIO21	Virtual screen enable
Black	GND	Ground
Red	5V/VIN	Power

Verify your wiring with a multimeter before powering on.

Setup

1. Copy the components/desk_height/ folder and flexispot-e7.yaml to your ESPHome config directory.

2. Create a secrets.yaml file (see secrets.yaml.example):

   wifi_ssid: "your_wifi_ssid"
   wifi_password: "your_wifi_password"
   api_encryption_key: "your_base64_key_here"
   ota_password: "your_ota_password_here"

3. Generate an API encryption key:

   [Convert]::ToBase64String((1..32 | ForEach-Object { Get-Random -Maximum 256 }) -as [byte[]])

   Or on Linux/macOS:

   openssl rand -base64 32

4. Flash to your ESP32:

   esphome run flexispot-e7.yaml

5. In Home Assistant, add the device using the API encryption key when prompted.

How It Works

The component communicates with the desk controller over UART at 9600 baud. Height data is returned as three 7-segment encoded display bytes.

On startup, the component sends a single M command to wake the display and retrieve the initial height. After that, it uses a silent wake command to poll for height changes without lighting up the desk's display.

Polling States

State	Poll Interval	Trigger
Boot	One-shot after 10s	Startup
Idle	Every 3s	Default after boot / movement stops
Active	Every 0.33s	Height change detected

The component returns to idle after 5 seconds of no height changes.

Exposed Entities

Sensors

• Desk Height - current height in cm
• WiFi RSSI - signal strength (dBm)

Buttons

• Preset 1 / Preset 2 - saved height presets
• Sit / Stand - sit and stand presets
• Up / Down - manual height adjustment
• Memory (M) - memory/preset save mode
• Wake - silently query the desk for its current height
• Reboot ESP - restart the ESP32

Troubleshooting

• "Unknown" or no height reading - Check wiring, especially the virtual screen pin (GPIO21). This must be held high for the desk to respond.
• Height not updating after boot - Check logs for the initial M command. If the desk doesn't respond, verify TX/RX wiring isn't swapped.
• Display lights up every few seconds - This should not happen. The idle/active polling uses the wake command which does not activate the display. If you see this, check that the firmware is up to date.

License

MIT License - See LICENSE.

Credits

Based on the work by NelsonBrandao and the ESPHome community's reverse engineering of the Flexispot UART protocol.