Home ├ Intro — two sentences, no slogan ├ Map example — screenshot + legend, link to the live map ├ At a glance — 5.9 GHz (ITS-G5/802.11p) · ESP32-C5, ~20 EUR │ · unencrypted but signable · MQTT · CC BY-SA 4.0 ├ Data flow — receive → publish via MQTT → the map ├ Running a receiver — official node OR your own project → Receivers ├ Documentation — link list to all pages └ Project — source (Codeberg) · talk (media.ccc.de/GLT26) · non-profit · imprint What is C-ITS? — conceptual only ├ How it works — 5.9 GHz, unencrypted but signable; vehicles <-> infrastructure └ Message types — CAM · DENM · MAPEM · SPATEM · IVIM Senders — who transmits C-ITS ├ Sender types — RSUs (traffic lights, roadworks signs, toll gantries) │ · OBUs (trams, buses, cars, emergency vehicles) ├ Vehicles: Volkswagen group— Golf 8, ID.3/4/5/7, ID.Buzz, Multivan, Tiguan III, │ Passat B9, Tayron, T-Roc II; >2.3M; changing pseudonyms ├ Vehicles: Cupra — Born (Tech Pack), Tavascan, Terramar ├ Not receivable — cloud "Car-to-X": Mercedes/BMW/Ford/Volvo/Audi/Skoda ├ Infrastructure — ASFINAG, Autobahn GmbH, Car2X traffic lights, transit OBUs ├ Outside Europe — USA DSRC (dead) · Japan ITS Connect 760 MHz │ · China C-V2X (both incompatible) └ In practice — what you actually receive around here Coverage — where C-ITS is live (purely geographic) ├ How this list works — deployment vs. community sighting; how to add one ├ Legend — signed yes/no, OBU-only, ... ├ Austria — Graz · Klagenfurt (12 RSU / 74 bus OBU) · Vienna · ASFINAG └ Germany — Autobahn · Aachen · Braunschweig · Hamburg (bus priority) · Kassel · Munich Receivers ├ The official receiver │ ├ Get one — group order (Pretix, 20 EUR, pickup at realraum Graz, │ │ shipping AT/DE/own label) · or have the PCB made │ ├ Board reference — ESP32-C5-WROOM, revisions, jumpers, u.FL, schematics │ ├ What's in the box — ASA enclosure, bottom seal (bottom.stl) + M4x12 TX20, │ │ rubber plug for the LAN cable │ ├ Power — USB (~1.7-2 W) vs. PoE; jumper table (802.3af / │ │ passive 7-58 V); never USB and PoE at the same time │ ├ Getting online — LAN/DHCP · no WiFi · mobile: repeater with LAN port │ ├ Config — no local web UI; via the portal (MQTT) or via USB │ ├ LEDs & troubleshooting — LED table (SYS/RCV/ETH/MQT/PKT), brightness │ ├ Compliance & EMC — EMC test rev 2 (FH Villach), class B passed; CE path │ └ Next steps — -> Placement · -> Your Node · -> Reporting to OTM │ └ Other receiver projects — catalogue; fields: hardware · firmware · uplink · to OTM? · repo ├ DIY Ethernet — ESP32-C5 + W5500/ENC28J60, OTM firmware, wired ├ WiFi via SPI-EPPP — ESP32-C5-DevKitC-1 (N4R2) + companion ESP32-C3 ├ USB -> Raspberry Pi — ESP32-C5 + Pi as gateway ├ USB -> Android — ESP32-C5 + phone as gateway (cits-to-go) ├ Mobile 5G setup — FireBeetle 2 ESP32-C5 + W5500 + power bank + ZTE MU5001 ├ ESPHome firmware — official OR any C5 hardware; esphome-its-g5 ├ FritzBox 3390 — AVM 3390 (AR9580/ath9k), OpenWrt + otm-bridge └ v2x2map — Waveshare C5-WIFI6-KIT, fork with its own app and map; standalone, OTM upload optional Placement & Outdoor ├ Mounting & line of sight — higher is better; outdoor beats indoor; tinted windows reflect ├ Interference — nearby 5 GHz WiFi -> separate or disable the 5 GHz band ├ Antennas & polarization — internal PCB antenna is good; external (u.FL): vertical better ├ Temperature — typ. ~55 C, up to 83 C in the sun; dim the LEDs; use shade ├ Enclosure — ASA (UV-resistant, waterproof), bottom seal + LAN grommet └ Surge protection — one arrester per outdoor run, inline before the switch, grounded Your Node — Self-Service Portal; applies to EVERY node ├ Accessing your node — QR code on the case / link from the shipping mail ├ Password protection — set a user password, otherwise the portal is open ├ Friendly name — a readable name instead of the raw MAC ├ Show on map & coordinates — map visibility, setting the location ├ Node settings — LED brightness (0-255), reboot ├ View your messages — your own frames in the portal └ Heatmap — reception heatmap of your node Reporting to OTM — the MQTT broker; convergence point of ALL receivers ├ The central broker — every node publishes to one broker -> the map; publish without login ├ Wire format — raw 802.11p/C-ITS frames; one format for all projects ├ Connecting — host/port from the firmware config.c; node name = MAC by default ├ Topics — its/nodeXXX/packet/json · .../stats · wildcard its/nodeXXX/# ├ Subscribe to your node — credentials from the portal; MQTT client list ├ What is published — CAM/DENM/MAPEM/SPATEM/IVIM + telemetry; no offline buffer └ Monitoring in Home Assistant — node publishes telemetry, HA reads along via MQTT (HA *as a receiver* -> ESPHome in the catalogue) Using the data — API (currently a stub) └ Overview · Endpoints · Data formats (GeoJSON/JSON) · Access & limits Community ├ Contributing — edit rights, style guide ├ Language policy — English ├ Non-profit & finances — OpenTrafficMap association, volunteer-run, donations ├ Related projects — Codeberg org, firmware repos, cits-to-go, EPPP server, │ v2x2map, esphome-its-g5, FritzBox bridge ├ Further reading — external C-ITS resources └ Imprint & license — CC BY-SA 4.0, imprint