# Capabilities & limitations

The PN532 is a **hosted NFC controller**, not a low-level RF lab instrument. This project exposes PN532 features honestly:

- **ISO14443-B**: reader support exists with **chip-level caveats** (anticollision / stack-dependent behavior). No promises of full mobile/PICC coverage.
- **Card emulation / TG modes**: PN532 firmware supports target commands and this repo now exposes a structured target-mode API, but real-world mimicry still depends on timing, UID size, ATS/general bytes, and reader expectations. Treat it as a controllable subsystem, not magic full-card impersonation.
- **Key recovery**: on-device “brute force” at Proxmark scale is **infeasible**. The UI provides **dictionary / manual** key workflows.
- **Signal / RF metrics**: diagnostics use **PN532 status / timings / retries**, not calibrated dBm.
- **OTA via UI**: `POST /api/ota` now performs real HTTPS OTA with the ESP-IDF certificate bundle. For production fleets, add your own release signing, manifest control, and hardware validation gates before broad rollout.