EtherPi (SNMP → LEDs + Sync + Display + Temps)

What it does

• Maps VLANs & link speeds from a UniFi switch (SNMP) to addressable LEDs
• Optional SPI display with rotating pages (overview, links, temps, sync)
• UDP multicast to sync VLAN colors across multiple Pis
• NEW: BMP280 sensor + Pi CPU temperature shown in UI and on display

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Hardware

• Raspberry Pi (any model with SPI + I2C; Pi 3/4/5 recommended)
• LED strip: WS2811 / WS2812 / WS2812B / SK6812 (RGB or RGBW)
• Small display (optional): SSD1351 OLED (128×128) or ST7789 LCD (e.g. 240×240)
• BMP280 temperature sensor (I2C; typical addr 0x76 or 0x77)
• Proper 5V power for LEDs; common ground with the Pi

Pin connections

LEDs (WS281x)

• Data → GPIO18 (physical pin 12) — default
• GND → any Pi GND (pins 6/9/14/20/25/30/34/39)
• 5V → external 5V supply (do not power long strips from Pi 5V)
• Share GND between Pi and LED PSU

Display (SPI0 default)

• VCC → 3.3V (pin 1 or 17)
• GND → GND
• SCK/SCL → GPIO11 (pin 23)
• MOSI/DIN → GPIO10 (pin 19)
• CS/CE0 → GPIO8 (pin 24)
• DC/RS → GPIO24 (pin 18)
• RST → GPIO25 (pin 22)
• (ST7789) BL/LED → 3.3V (or map to a GPIO if you want control)

BMP280 (I2C)

• VCC → 3.3V
• GND → GND
• SDA → GPIO2 (SDA1) (pin 3)
• SCL → GPIO3 (SCL1) (pin 5)
• Default address 0x76 (some boards use 0x77)

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Software install

git clone https://github.com/Lukeskaiwalker/etherlight-pi
cd etherlight-pi
./install.sh

To keep onboard audio enabled:

DISABLE_AUDIO=0 ./install.sh

The script:

• Installs OS deps (Python, build tools, SNMP, I2C tools, scons)
• Enables SPI (display) and I2C (BMP280)
• Creates a .venv and installs Python deps (Flask, PySNMP, rpi-ws281x, luma, smbus2, bmp280)
• Installs a systemd service that uses the venv and starts the app
• Disables onboard audio by default (set DISABLE_AUDIO=0 to keep audio); reboot recommended after changes

Open: http://<pi-ip>:8080/

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Update

From the UI

• Go to Setup → Service.
• Check for updates (requires internet on the Pi).
• Update via Git to pull the latest release and restart the service.
• Offline update: download a release .zip/.tar.gz from GitHub on another machine, then upload it on the Service card.
• Updates keep your local settings in config.local.json.

Manual

cd ~/etherlight-pi
git pull
./install.sh

If you move the repo, rerun the install so the systemd service points at the new path.

Versioning

Releases use YYYY.MM.N (year, month, increment). Example: 2026.01.1. Use scripts/bump_version.py to increment the month counter and update VERSION.

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Configuration

• Edit config.local.json (auto-created on first run, preserved across updates).
• config.json is the template shipped with the repo.
  • device.switch_host / device.snmp.community
  • device.ports.count if auto-detect differs
  • led.* for type/order/pin/brightness
  • display.enabled and model/size
  • sensors.bmp280.enabled, bus, address (0x76 or 0x77)
• If device.name is empty or EtherPi, it auto-sets to EtherPi-XXXX (based on MAC).

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UI

• Temperatures card shows: CPU and BMP280 in °C (live).
• Live Ports table: ifName, VLAN, speed, link state.
• VLAN → Color editor.
• Detect switch button fills model + port count.

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Troubleshooting

• LED mmap()/PWM error: rerun DISABLE_AUDIO=1 ./install.sh (or ./fix-ws281x-root-audiooff.sh) and reboot; ensure GND shared.
• No BMP280 reading: enable I2C, check wiring & address (0x76 vs 0x77). Use i2cdetect -y 1 to confirm presence.
• BMP280 auto-disabled: if no sensor is detected at boot it is turned off in config; re-enable in Setup → Sensors after wiring.
• Display blank: confirm SPI enabled; ensure spidev is installed in the venv (rerun ./install.sh); check driver/size in config.local.json and wiring.

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Service

journalctl -u etherlight.service -f
sudo systemctl restart etherlight.service