====== er-01-rev-a ======

Universal I/O module for the Wonder Controlz escape room system. Connects to the CAN bus and provides PWM outputs, digital inputs, servo outputs, and USB HID host — all controlled remotely from Node-RED on the Main PC.

The module contains **no game logic**. It executes commands received over CAN and reports input state changes back. This means a failed unit can be replaced in minutes — plug in a new one, set the CAN address with buttons, and it works immediately.

**Status:** Production (actively deployed in escape rooms).\\
**Successor:** [[products:er-dio-01|er-dio-01]] (in development).

===== Power =====

Input supply is **24V DC** via the CAN bus cable (4 wires: 24V, GND, CAN_H, CAN_L).

The module has built-in DC-DC converters that produce 12V and 5V internally:

^ Rail ^ Max Current ^ Used for ^
| 24V | pass-through | Available on dedicated output connector |
| 12V | 4 A | PWM outputs (default) |
| 5V | 4 A | USB port, servo connectors, dedicated 5V output |

Idle power consumption: < 0.7 W.

===== PWM Outputs (×8) =====

Low-side switching via N-channel MOSFETs (switched ground).

^ Parameter ^ Value ^
| Channels | 8 |
| Max current per channel | 2.5 A |
| Total current (all channels) | 4 A (limited by 12V converter) |
| PWM resolution | 0–1000 (smooth dimming, motor speed control) |

**Voltage flexibility:** Since the outputs switch the ground side, the positive supply can be 5V, 12V, or 24V — depending on what the connected device needs. One module can control devices at different voltages.

**Protection:**
  * Thermal overcurrent protection on each MOSFET
  * Flyback clamping diodes (up to 100 mJ) — safe for inductive loads such as electromagnetic locks

===== Digital Inputs (×8) =====

Dry-contact (potential-free) inputs for sensors and switches.

^ Parameter ^ Value ^
| Channels | 8 |
| Type | Dry contact (active LOW) |
| Debounce | Hardware RC filter, ~10 ms (PLC-grade) |
| Current through closed contact | < 4 mA |

**Compatible sensors:** reed switches, pushbuttons, limit switches, PIR sensors (dry contact output), Hall sensors, relay contacts.

State changes are reported to the Main PC automatically over CAN.

===== Servo Outputs (×16) =====

Standard RC servo outputs with smooth motion profiles.

^ Parameter ^ Value ^
| Channels | 16 (two 8-channel connectors) |
| PWM frequency | 50 Hz (standard RC servo) |
| Position range | 0–1000 (mapped to configurable pulse width) |
| Connector pinout | +5V / Signal / GND per channel |

**Ramp profiles** for smooth, controlled motion:

^ Profile ^ Description ^
| LINEAR | Constant speed, instant start/stop |
| SMOOTHSTEP (5 levels) | Gradual acceleration/deceleration — from gentle (15%) to very smooth (50%) |

Ramp time is configurable from instant to 25.5 seconds.

===== USB HID Host =====

^ Parameter ^ Value ^
| Power output | 5V, max 500 mA |
| Overcurrent protection | Yes (hardware) |

**Supported devices:** HID-class keyboards, mice, barcode scanners, RFID readers (HID mode).

USB HID events (key presses, mouse movements, scans) are forwarded to the Main PC via CAN bus.

===== CAN Bus =====

^ Parameter ^ Value ^
| Standard | CAN 2.0A |
| Baud rate | 500 kbps |
| Protocol | ER-Frame (custom) |

The module receives commands (set PWM, move servo, emergency stop) and sends events (input changed, servo position reached, USB HID event) over the CAN bus using the ER-Frame protocol.

===== Front Panel =====

^ Element ^ Description ^
| Display | 4-digit, 7-segment LED |
| Buttons | 3 — SEL, PLUS, MINUS |
| Status LEDs | RUN (green), STOP (yellow), ERROR (red) |

The CAN device address (1–255) is set using the +/- buttons and persists across power cycles.

===== Wiring =====

**Bus cable (4 wires):**
  * 24V + GND — power
  * CAN_H + CAN_L — communication

**Minimum wire cross-section:** 1 mm² (for all power and output wiring).

**Topology:** Daisy-chain bus with 120 Ω termination resistors at both ends.

===== Specifications Summary =====

^ Feature ^ Value ^
| PWM outputs | 8× (2.5 A each, 0–1000 resolution) |
| Digital inputs | 8× (dry contact, 10 ms debounce) |
| Servo outputs | 16× (50 Hz, 6 ramp profiles, up to 25.5 s ramp time) |
| USB HID host | 1× (keyboard, mouse, scanner) |
| CAN bus | 500 kbps, ER-Frame protocol |
| Supply voltage | 24V DC |
| Built-in converters | 12V / 4 A + 5V / 4 A |
| Idle power | < 0.7 W |
| Configuration | 7-segment display + 3 buttons |