Glossary

Key terms and concepts used throughout the Wonder Controlz documentation.

Architecture & Principles

Term	Definition
Zero Field Logic	The core design principle of Wonder Controlz. No device in the room contains any game logic — all decision-making happens in Node-RED on the Main PC. Field devices only execute commands and report events.
Main PC	The central computer of the installation. Runs Node-RED (game logic), er-audio (if used), and any other software. All other devices in the room are controlled from the Main PC. Typically a BeeLink mini-PC running Linux.
CAN bus	The communication bus connecting I/O modules to the Main PC. A single 4-wire cable (24V + GND + CAN_H + CAN_L) carries both power and data. Industrial standard, used in automotive and factory automation.
ER-Frame	The custom communication protocol used over CAN bus. Carries commands (set PWM, move servo) and events (input changed, card detected) between the Main PC and I/O modules.
Node-RED	Open-source visual programming environment used for all game logic. Runs on the Main PC. Scenarios are built by connecting nodes in a flow — no traditional coding required.

Term	Definition
I/O module	A hardware device on the CAN bus that provides inputs and outputs for props and puzzles. Contains no game logic. Examples: er-01-rev-a, er-dio-01.
Reader module	An RFID/NFC card reader connected to er-rfid via RS-485. Placed near or inside a prop where players present cards.
Software product	An application that runs on the Main PC or a dedicated mini-PC. Controlled via HTTP REST API from Node-RED. Examples: er-audio, mpv-control.
Hardware + Software	A product consisting of a dedicated hardware controller paired with a PC application. Example: er-lights (LED/DMX controller + animation engine).

Term	Definition
24V SELV	Safety Extra-Low Voltage (IEC 61140). The recommended operating voltage for Wonder Controlz installations. Safe to touch, no risk of electric shock.
PWM output	Pulse Width Modulation output on an I/O module. Controls brightness (LEDs, lamps) or speed (motors) smoothly, with values from 0 (off) to 1000 (full power). Low-side MOSFET switching.
Dry contact input	A digital input that detects whether a circuit is open or closed. Compatible with standard sensors: reed switches, buttons, limit switches, PIR sensors.
Ramp profile	A motion curve for servo outputs. Controls how a servo moves from one position to another — from instant (LINEAR) to smooth acceleration/deceleration (SMOOTHSTEP).

Term	Definition
VPN	Secure remote connection to an installation. Used for diagnostics, software updates, and scenario changes without visiting the site. The room operates fully offline — VPN is for service only.