homebridge-systemline-s62-control

A Homebridge plugin for the Systemline S6.2 multi-room audio system. Each zone appears as a TV accessory in HomeKit with source selection and volume control via a Global Cache iTach IP2SL RS232 interface.

Looking for switch-based control? See homebridge-globalcache-gc100-kiro which exposes zones as simple on/off switches — useful for automations that don't need source selection.

Overview

The Systemline S6.2 is an 8-zone multi-room audio matrix amplifier with an RS232 control interface but no native IP connectivity.

This plugin bridges that gap using a Global Cache iTach IP2SL — a network-to-serial adapter — to expose each S6.2 zone as a HomeKit TV accessory. You can then control your whole-home audio from the Apple Home app, Siri, or any HomeKit automation.

What you can do from HomeKit:

• Turn individual zones on or off
• Select the source for each zone (Sky Q, Apple TV, etc.) using the TV input picker
• Control volume per zone via a brightness slider
• Use volume up/down buttons in the TV remote UI
• Include zones in automations and scenes

How it works

HomeKit
    ↓
Homebridge plugin (Pi)
    ↓
TCP socket → iTach IP2SL port 4999
    ↓
RS232 serial output
    ↓
Systemline S6.2

Each zone is a TV accessory containing:

• Television service — power on/off and source selection
• TelevisionSpeaker service — volume buttons in the TV remote UI
• Lightbulb service — brightness slider = volume (0–100% maps to S6.2 range 0–30)
• InputSource services — one per configured source

State is cached at startup and after every change, so HomeKit responses are instant.

Requirements

• Homebridge v1 or v2
• Global Cache iTach IP2SL (network-to-serial adapter)
• Systemline S6.2 multi-room amplifier
• iTach IP2SL connected to the S6.2 RS232 port and reachable on your local network

iTach IP2SL serial port configuration

Configure the iTach serial port via its web UI at http://<itach-ip>:

| Setting | Value | |---------|-------| | Baud rate | 9600 | | Data bits | 8 | | Parity | None | | Stop bits | 1 | | Flow control | None |

Installation

npm install -g homebridge-systemline-s62

Or install via the Homebridge UI plugin search.

Configuration

Add the platform to your Homebridge config.json. The plugin is best configured via the Homebridge UI which provides a form-based editor.

{
  "platform": "SystemlineS62",
  "name": "Systemline S6.2",
  "host": "192.168.1.x",
  "port": 4999,
  "sources": [
    { "id": 1, "name": "Sky Q Mini" },
    { "id": 2, "name": "Sky Q" },
    { "id": 6, "name": "Apple TV" }
  ],
  "zones": [
    { "id": 1, "name": "Bedroom 1" },
    { "id": 2, "name": "Kitchen" },
    { "id": 3, "name": "Lounge" },
    { "id": 8, "name": "Garden" }
  ]
}

Configuration options

| Option | Required | Default | Description | |--------|----------|---------|-------------| | host | ✅ | — | IP address of the iTach IP2SL | | port | | 4999 | TCP port on the iTach | | sources | ✅ | — | Array of sources (see below) | | zones | ✅ | — | Array of zones (see below) |

Sources

Define the sources connected to your S6.2 by their S6.2 source number (1–6) and a friendly name. Only define the sources you actually use — unused sources can be omitted.

"sources": [
  { "id": 1, "name": "Sky Q Mini" },
  { "id": 2, "name": "Sky Q" },
  { "id": 6, "name": "Apple TV" }
]

Zones

Define the zones you want to control by their S6.2 zone number (1–8) and a friendly name.

"zones": [
  { "id": 1, "name": "Bedroom 1" },
  { "id": 2, "name": "Kitchen" },
  { "id": 8, "name": "Winter Lounge" }
]

Adding zones to HomeKit

TV accessories are registered through the main Homebridge bridge — no separate pairing needed. After restarting Homebridge, the zone accessories will appear in the Homebridge UI → Accessories tab. Add each one to HomeKit from there.

How it works internally

The S6.2 RS232 protocol uses simple ASCII commands:

| Action | Command | |--------|---------| | Select source | $s<zone>src<source>\r | | Zone off | $s<zone>srcoff\r | | Query source | $g<zone>src\r | | Set volume | $s<zone>vol<0-30>\r | | Query volume | $g<zone>vol\r | | Mute | $s<zone>volmute\r | | Unmute | $s<zone>volmoff\r |

All commands are serialised through a shared queue so only one TCP socket is open at a time, preventing cross-zone response collisions. Volume changes are debounced (400ms) so dragging the slider doesn't flood the amplifier.

Credits

Systemline S6.2 RS232 protocol Documented in the Systemline S6.2 installation manual.

Based on homebridge-globalcache-gc100-kiro — the switch-based predecessor to this plugin.

Built with Kiro AI This plugin was designed and built with Kiro, an AI-powered development environment.

License

MIT