Switch Control¶

A Python program and web UI for controlling a cryogenic RF switch.

Switch Control UI

The backend drives an 8-channel numato USB relay board over a serial connection. The relay board routes positive and negative voltage pulses into a binary tree of Teledyne latching relays, which switches one pair of SMA inputs to one of eight differential output pairs on an ARC6-8ch connector.

The voltage pulses themselves are produced by a function generator — on this lab's hardware, a Teledyne T3AFG200 reached over a shared instrument socket server. See Hardware configuration for how a given machine selects its pulse generator.

What's here¶

Quickstart Install dependencies, build the UI, and launch the app.
Hardware configuration system_settings.yml, pulse-generator selection, and enabling hardware.
Architecture The reactive lab-link backend, the Svelte UI, and remote access.

At a glance¶

Backend entrypoint: backend/backend/main.py — a lab-link + Starlette server hosting an integrated pywebview window.
Frontend: a Svelte app in switch_control/, built with Bun and Vite.
State model: the backend's reactive AppState is the single source of truth; the browser receives snapshots and JSON patches over a lab-link WebSocket and sends hardware operations as lab-link commands (no REST polling, no SSE).
Package management: uv for Python, Bun for the web assets.