board

A real-time transit departure board built with Slint, displaying arrivals from the OneBusAway Puget Sound API.

Designed to run on a PROXmobil3 with a framebuffer display, but also works as a desktop window for development.

Configuration

Requires the OBA_API_KEY environment variable to be set with an OneBusAway Puget Sound API key. Email oba_api_key@soundtransit.org to request one.

Usage

board <stop_name> <stop_id> [stop_id...]

Example:

OBA_API_KEY=your-key cargo run -- "University District" 40_990001 40_990002

Building

Desktop (x86, windowed)

OBA_API_KEY=your-key cargo run -- "University District" 40_990001 40_990002

ARM (PROXmobil3, framebuffer)

cargo zigbuild --release --target armv7-unknown-linux-gnueabihf.2.28 --no-default-features --features framebuffer

Deploying to PROXmobil3

1. Build the ARM binary (see above).

2. Copy the binary to the device over SSH:

   cat target/armv7-unknown-linux-gnueabihf/release/board | ssh root@<DEVICE_IP> 'cat > /init/board/exe && chmod +x /init/board/exe'
   

3. Create the systemd service at /init/board/board.service on the device:

   [Unit]
   Description=Board Display Service
   After=network.target
   
   [Service]
   Type=simple
   Environment=OBA_API_KEY=your-key
   ExecStart=/init/board/exe "Your Stop Name" your_stop_id your_stop_id2
   Restart=always
   RestartSec=2
   WorkingDirectory=/init/board
   
   [Install]
   WantedBy=multi-user.target

4. Create the autorun script at /init/autorun/99-board.sh to install the service on boot:

   #!/bin/sh
   
   mount -o remount,rw /
   
   # Set timezone (adjust as needed)
   ln -sf /usr/share/zoneinfo/America/Los_Angeles /etc/localtime
   
   # Disable default PM3 UI
   systemctl stop nx
   systemctl mask nx
   systemctl stop init-abtproxy
   systemctl mask init-abtproxy
   
   # Install and start board service
   cp /init/board/board.service /etc/systemd/system/
   systemctl daemon-reload
   systemctl enable board.service
   
   mount -o remount,ro /
   
   /usr/bin/NxExe watchdog 0
   
   systemctl start board.service

5. To update the stop or API key later:

   ssh root@<DEVICE_IP>
   mount -o remount,rw /
   vi /init/board/board.service
   mount -o remount,ro /
   systemctl daemon-reload
   systemctl restart board.service
   

Debug CLI

Inspect raw API data and see how arrivals are deduplicated:

OBA_API_KEY=your-key cargo run --bin debug_arrivals -- "University District" 40_990001 40_990002

Development

Uses Nix for the development environment:

nix-shell

License

MIT