The Blackmagic Design GPI and Tally Interface is a specialized interface box designed to integrate ATEM live production switchers with external equipment and control systems using simple contact closure signals. It serves as a crucial bridge, allowing the switcher to be triggered by, or to send status signals to, a wide variety of third-party devices such as stage lighting controllers, robotic camera systems, broadcast automation servers, and audio mixers.

The unit provides multiple General Purpose Interface (GPI) inputs that can detect a dry contact closure from an external device, which can then be mapped within the ATEM software to trigger specific actions like cutting to a preset, starting a media player clip, or changing camera angles. Conversely, its tally outputs provide isolated relay contacts that close in response to the switcher's program and preview bus status, enabling the control of external tally lights, VTR record triggers, or other indicator systems.

Housed in a compact and durable metal enclosure, the interface is engineered for reliable operation in the electrically noisy environments typical of broadcast facilities and live event production. It connects to an ATEM switcher via a standard Ethernet cable, seamlessly integrating into the ATEM ecosystem without requiring complex configuration. By translating between the switcher's digital control logic and the universal language of simple electrical contacts, this interface significantly expands the automation and interoperability capabilities of an ATEM-based production system.

It is an essential tool for broadcast engineers and system integrators who need to synchronize their video switcher with the broader technical infrastructure of a studio or live event, enabling more streamlined, automated, and professional workflows.