# USB/reset/LED autoroute — run on your Mac, then import the .ses

**DSN:** `hbox-watchdog-v3-PROD-usb.dsn` — the current 132-part board **with your existing
routing already in it** (1069 wires) + the 9 new nets unrouted. So FreeRouting starts with
"incomplete" ≈ the 9 new connections and should drive to **0** almost immediately — it's only
routing USB_VBUS/DP/DM, USB_CC1/CC2, MODEM_RST, MODEM_LED(_A). GND rides the In1 plane.

Clearance 0.2 mm, width 0.2 mm (fine for these low-current USB/signal nets).

## 1. Route it

Headless (simplest):
```bash
cd "/Users/leo/Documents/Claude/Projects/Drogheda/03-Architecture-Hardware/kicad"
java -jar freerouting-1.9.0.jar \
  -de hbox-watchdog-v3-PROD-usb.dsn \
  -do hbox-watchdog-v3-PROD-usb.ses \
  -mp 30
```

Or GUI (more control): `java -jar freerouting-1.9.0.jar` → **File → Open Design** →
`hbox-watchdog-v3-PROD-usb.dsn` → watch the **incomplete** count fall to 0 → **File → Export
Specctra Session File** → `hbox-watchdog-v3-PROD-usb.ses`.

> The DSN carries your existing traces, so FreeRouting mostly just fills in the 9 new nets. If you
> want to be conservative and let it touch the existing routing as little as possible, stop as soon
> as incomplete hits 0 (GUI) — no need to let it grind optimization passes.

## 2. Bring it back into KiCad
Open the board → **File → Import → Specctra Session** → `hbox-watchdog-v3-PROD-usb.ses` →
press **B** to refill the In1 GND plane → **Inspect → Design Rules Checker**.

Paste me the DRC summary and I'll help clear anything real before you fab. **Do not run F8** —
the parts are already placed; you're only importing routing now.

## 3. Fab
Re-export the JLCPCB package (Gerbers + drill + BOM + CPL), order as **4-layer** (F.Cu / In1 GND /
In2.Cu / B.Cu, JLC 1.6 mm standard).