Blackmagic GPI and Tally Interface

Adds GPI and tally interface to a Blackmagic ATEM switcher. With 8 contact closure tally outputs, you can send a tally signal to your cameras, replay machines and monitors so everyone knows which camera is ‘on-air’. If you need more tally outputs, simply connect multiple GPI and Tally Interfaces together because it connects via Ethernet to your ATEM production switcher.