AV.link
AV.link is a control protocol carried over SCART connections, standardized by CENELEC as EN 50157-1. It enables automated control and status communication between connected AV devices.
Overview
AV.link provides a standardized way for SCART-connected devices to communicate control commands and negotiate signal types. It evolved from earlier proprietary protocols like D²B and is also known by various trade names including SmartLink, Q-Link, EasyLink, and NexTViewLink.
Specifications
| Parameter | Value |
|---|---|
| Standard | CENELEC EN 50157-1 |
| Physical layer | Single-wire serial bus |
| SCART pins | 10 and 12 (active low data) |
| Voltage | TTL levels |
Features
- Automatic input switching when source device powers on
- Aspect ratio signaling (4:3 / 16:9)
- Standby control (power on/off synchronization)
- Signal type negotiation (composite/RGB/S-Video)
- VCR timer recording coordination
Relationship to CEC
AV.link's functionality was carried forward into HDMI's Consumer Electronics Control (CEC) feature, which provides similar automation capabilities for digital connections.
