# Zone QR codes

A parking-zone QR code just encodes the zone's **`ScannerCode`** as plain text.
BigBrainParking's scanner (and the official ParkSmarter app) resolve that code to
the zone. No URL, no wrapper — the raw scanner code is enough.

## Make one

```bash
qrencode -o my-zone.png -s 14 -m 4 "<ScannerCode>"
```

`<ScannerCode>` is the zone's `ScannerCode` field (visible on the meter detail
screen, or in a `/api/Meter` response). For the DL zone in Sandpoint it's `DL`:

```bash
qrencode -o DL-sandpoint.png -s 14 -m 4 "DL"
```

![DL zone, Sandpoint](DL-sandpoint.png)

## Which field to encode

Use **`ScannerCode`** — it's what physical kiosk QR stickers encode and the only
field the official ParkSmarter app accepts when scanning.

- `ScannerCode` — ✅ works in BigBrainParking **and** the official app.
- `ZoneName` (e.g. `dl`) — works as a fallback in BigBrainParking (case-sensitive
  server-side; the app tries the lowercased form too).
- `TerminalSerNo` (e.g. `30004246`) — uniquely identifies the terminal and works
  in BigBrainParking, but the **official app rejects a bare serial** ("not
  recognized as a ParkSmarter zone"), so don't use it for cross-app QR codes.

When BigBrainParking scans a code it tries, in order: `ScannerCode → ZoneName →
zonename(lowercased) → TerminalSerNo`, each independently, so any of these
resolve.