External Control APIs

Q-SYS is designed to allow third-party systems to control and monitor various aspects of the system – including controls from Inventory and Schematic Library components in your design – via custom code.

There are multiple External Control APIs available. Click a link to learn more.

Q-SYS Remote Control Protocol (QRC)

QRC is a Unicode-based TCP/IP control protocol and is the newest and most advanced API for external control of the Q-SYS system. The client connects to the Q-SYS Core processor on port 1710 and sends JSON RPC 2.0 null-terminated commands. QRC includes a separate set of API commands for PA Router control.

External Control Protocol (ECP)

ECP is a legacy external control API that is still supported in all versions of Q-SYS. The client connects to the Q-SYS Core processor using a TCP/IP connection on port 1702.

Q-SYS Communications Library

The Q-SYS Communications Library is an alternative to connecting and controlling a Q-SYS Core processor directly via a TCP/IP connection. It presents connection, status, control, and monitoring of a Core at a higher level than direct TCP/IP socket communications, and thus is easier to use.

Change Groups for ECP and QRC

A Change Group is a grouping of controls, created by your code, that is polled at a schedule interval. When the Change Group is polled, it returns the state of any controls that have changed since the last polling.