2 Commits

Author SHA1 Message Date
fee8d9c1f9 Add USB CDC serial command interface for RF test bench control
Line-based JSON protocol over the ESP32-S3 native USB OTG port,
providing deterministic sub-millisecond attenuator control without
WiFi interference. Runs alongside the existing REST API.

Commands: identify, status, config, set, sweep, sweep_stop
Protocol: usb-serial-json-v1 (one JSON object per \n-terminated line)

Also addresses pre-existing reliability issues found during review:
- Thread safety: FreeRTOS mutex in Attenuator class (web server
  callbacks run on async_tcp task, not loop())
- NVS flash wear: skip persist during sweep, save on stop
- WiFi credentials: moved to gitignored platformio_local.ini
- Shared header: sweep.h replaces duplicated extern declarations
2026-02-18 13:46:52 -07:00
613611d37a Add ESP32-S2 firmware for HMC472A attenuator control
PlatformIO/Arduino firmware for WEMOS/LOLIN S2 Mini:
- 6-bit GPIO control (GPIOs 1-6) with glitch-free register writes
- REST API: /status, /set, /config, /sweep endpoints
- Web UI with PCB green theme, slider, presets, pin visualization
- NVS persistence of attenuation setting across power cycles
- Sweep mode for automated attenuation stepping
- mDNS (attenuator.local), OTA updates, watchdog
2026-02-02 21:24:29 -07:00