Prepare the microSD card

Use a FAT32 card for the initial hardware checks. Copy the lora-tunnel directory to the card root, then copy config.example.json to config.json on the card. The firmware creates /sessions and a new LT-xxxxxxxx.jsonl file for each session. Keep the original JSONL files when exporting.

The user confirmed United States operation on 2026-11-01 for the 915 MHz hardware. Both 0.1.1-dev built-in defaults and the example therefore set lora.enabled=true for receive-only US Meshtastic LongFast: 906.875 MHz, BW250, SF11, CR4/5, preamble 16, sync 0x2B. The regional selection is confirmed; the specific PCB revision and fitted RF front-end still require the hardware checks in docs/HARDWARE.md. The sync word is fixed in this first build. LNA starts in bypass for bench comparison. No transmit function is provided. Copy the example to config.json and reboot to load it; reboot after later radio or detection changes too.

When neither config.json nor config.bak exists, firmware uses those confirmed US defaults. If existing configuration cannot be read/validated, firmware first tries config.bak; without a valid backup, LoRa is disabled and the screen reports the configuration problem. An invalid radio section also disables LoRa. A missing file and a damaged existing file therefore have different recovery behavior. SD storage is still required to start a recording session.

config.json accepts at most 16 KiB, with strings bounded to 127 characters for credentials. Settings > a credential opens the keyboard only when needed. Stop capture before saving. A temporary file is written, checked, and promoted; a previous valid config.bak is retained. When creating a configuration through the keyboard, the current radio settings are retained. FAT filesystem updates cannot guarantee atomicity against every card/power failure. Full interruption tests remain required.

The WiGLE API name/token, WDGWars token, Wi-Fi SSID and Wi-Fi password can be entered in this file or on the touchscreen. This milestone stores them but does not connect or upload. An automatic-upload policy and uploader will be added after offline capture/export acceptance. Credentials are plaintext on removable storage as requested: treat the card as containing those credentials. Firmware never prints credential values or includes them in session logs. Do not add your real config to source control.

Recon has a built-in passive signature engine and an embedded vendor table. It works when detection_rules.json has an empty rules array. Optional SD rules add your own evidence; they are not required to enable the built-in detections. detection_rules.json accepts up to 64 valid rules and 16 KiB. Add entries in rules, for example:

{"type":"name","match":"My test beacon","label":"Owned test beacon","alert":true}

An OUI entry uses type:"oui" with a verified colon-separated 24-bit prefix, plus a label and alert. Vendor prefixes are used only for globally assigned unicast Wi-Fi addresses and public/public-identity BLE addresses. Randomized or locally administered addresses are never mapped to an OUI vendor. A name rule is an exact case-insensitive name match. Additional types are ssid_prefix (Wi-Fi only), service16 (BLE service list or service data), and manufacturer (BLE company ID). BLE identifiers use four hex digits, optionally prefixed by 0x.

Rules indicate a match to the supplied evidence, not verified device identity or purpose. Broadcast names and manufacturer fields can be copied or spoofed. category selects one of the documented Recon categories; confidence is low, medium or high. A legacy rule without category is always a custom low-confidence match. Rules only replace a result with a stronger configured grade; equal-grade built-in evidence wins. alert:false suppresses the alert only when that rule supplies the winning classification. It is not a global mute for a device already identified by stronger evidence.

detection_rules.example.json contains a few optional examples. Keep the loaded detection_rules.json empty unless you want custom rules. vendor-prefixes.csv is the editable 201-row evidence reference with attribution in vendor-prefixes.README.md; the firmware uses its compiled table and does not automatically import this CSV. To add or change a runtime OUI rule, use detection_rules.json. Full evidence and format notes are in docs/RECON.md and schemas/detection-rules-v1.schema.json in the source tree.

In config.json, recon.display_min defaults to low, recon.alert_min defaults to medium, and recon.buzzer defaults to true. recon.categories optionally lists enabled category keys; omission enables all and an empty array disables all. ui.buttons_enabled defaults to true for the physical-button shortcuts. Optional fields with invalid types or values retain their defaults. Reboot after editing the card. Recon filtering is independent of ordinary Wardriver capture and logging.

If the card is missing at boot, the screen/GNSS remain available. Insert a card, then Setup > Retry SD. Reboot to load its configuration. Start refuses a missing card; a card failure during capture is visible and increments errors/drops. Stop must finish before removing the card. Power loss can lose the current RAM buffer; complete prior JSONL lines remain independently readable.