Gate Link

ESP32 firmware for a two-leaf gate controller, exposed to Home Assistant over MQTT with MQTT Discovery. No manual YAML entity setup needed.

no_std Rust on the Embassy async executor (via esp-rtos), targeting xtensa-esp32-none-elf.

Features

• Open / close / stop, plus impulse control (local push button and radio remote) with the classic open → stop → close → stop → open press cycle
• Two independent light barriers: one stops the gate outright, the other only blocks closing
• Wind guard (anemometer) input that force-opens and locks the gate until explicitly reset (dedicated input or an MQTT button)
• Gate leaf position and wind-lock state persisted to flash, so a power loss doesn't lose track of where the gate was
• First-boot provisioning: the device opens its own Wi-Fi hotspot with an HTTP form to collect Wi-Fi + MQTT settings — no hardcoded credentials

Hardware / wiring

All GPIO assignments, motor travel durations and input polarity are hardcoded in src/bin/main.rs — edit run_station_mode's wiring section to match your installation. Default pinout:

Signal	GPIO
BOOT button (config reset)	0
Local push button	4
Radio remote	13
Wind sensor (anemometer)	16
Wind lock reset	17
Light barrier 1	18
Light barrier 2	19
Left leaf: open relay	25
Left leaf: close relay	26
Right leaf: open relay	27
Right leaf: close relay	14

All inputs are active-low with an internal pull-up. Leaf travel time defaults to 15s per motor (LEFT_/RIGHT_MOTOR_DURATION_SECS in main.rs).

Building

The toolchain is pinned via rust-toolchain.toml to the esp channel, installed with espup. The target (xtensa-esp32-none-elf) and build-std are already configured in .cargo/config.toml, so no extra flags are needed:

cargo build --release              # what CI builds
cargo fmt --all -- --check
cargo clippy --all-features --workspace -- -D warnings
cargo run                          # builds, flashes and opens a serial monitor via espflash

First boot / provisioning

1. On first boot (or after a config reset), the device has no stored Wi-Fi credentials and opens an open (passwordless) hotspot named mqtt-gate-setup at 192.168.2.1.
2. Connect to it and open http://192.168.2.1/ to fill in the Wi-Fi SSID/ password and MQTT broker host/port/credentials.
3. Submitting the form persists the config to flash and reboots the device into station mode, where it joins your Wi-Fi and connects to the broker.
4. To reprovision, hold the onboard BOOT button (GPIO0) for 5 seconds during boot — this erases the stored config and drops back into provisioning mode.

Home Assistant integration

On connecting to the broker, the device publishes retained MQTT Discovery configs for three entities:

Entity	Type	Notes
Gate (mqtt_gate_cover)	Cover	open / close / stop, reports position
Windwächter (mqtt_gate_wind)	Binary sensor	on while the wind lock is engaged
Windwächter zurücksetzen (mqtt_gate_reset_anemometer)	Button	clears the wind lock

No manual entity configuration in Home Assistant is required — they appear automatically once the device connects.