====== Architecture ======

Wonder Controlz follows a **centralized logic, decentralized I/O** approach — inspired by industrial automation (PLC + fieldbus).

<code>
                         ┌──────────────────────┐
                         │       Node-RED       │ ← Central game logic
                         │      (Main PC)       │    All scenarios in one place
                         └──────────┬───────────┘
                                    │
                    CAN bus ────────┼──────── HTTP REST
                 (I/O modules)     │       (media, lights)
                                    │
       ┌──────────┬──────────┬──────┼──────┬───────────┬───────────┐
       ▼          ▼          ▼      ▼      ▼           ▼           ▼
   ┌────────┐ ┌────────┐ ┌──────┐ ┌──────────┐ ┌───────────┐ ┌───────────┐
   │er-01-  │ │er-dio- │ │er-   │ │ er-audio │ │ er-lights │ │mpv-control│
   │rev-a   │ │01      │ │rfid  │ │  audio   │ │ lighting  │ │  video    │
   └────────┘ └────────┘ └──────┘ └──────────┘ └───────────┘ └───────────┘
</code>

===== Zero Field Logic =====

The core design principle of Wonder Controlz. **No device in the room contains any game logic.** I/O modules, media players, and lighting controllers only execute commands and report events. All decision-making lives in one place: [[https://nodered.org/|Node-RED]] on the [[glossary#main_pc|Main PC]].

This means:
  * A broken module can be replaced in 2 minutes — plug in a new one, set the address, done. No reprogramming, no re-teaching
  * Scenarios can be changed remotely — no need to physically access any device
  * Full room backup is a simple Node-RED flow export — restore the entire room on new hardware in minutes
  * All debugging happens from one screen — input states, output states, CAN traffic, all visible in real time

===== Communication =====

==== CAN Bus — I/O Modules ====

All [[glossary#i_o_module|I/O modules]] connect to the Main PC via a **single 4-wire CAN bus** cable (24V + GND + CAN_H + CAN_L). The cable carries both power (24V) and data (500 kbps). Messages use the custom [[glossary#er-frame|ER-Frame]] protocol.

==== HTTP REST — Software Products ====

Software products ([[products:er-audio|er-audio]], [[products:mpv-control|mpv-control]], [[products:er-lights|er-lights]]) are controlled via HTTP REST API. All endpoints use GET requests for seamless integration with Node-RED's HTTP request node.

==== Ethernet UDP — Lighting Hardware ====

The [[products:er-lights|er-lights]] hardware controller receives lighting data over Ethernet (UDP port 5568) using the ERLED480 or sACN/E1.31 protocol.