Using Tally
103
Sending Tally Signals via a GPI and Tally Interface
Your ATEM switcher can send tally signals to monitors and cameras to make it clear which source is on the
program output, i.e. which source is on air.
Tally is commonly used to light the red light on top of a camera or monitor so the talent knows they are on
air. Tally can also illuminate a border on a monitor such as a Blackmagic SmartView Duo or SmartView HD.
The border allows production staff to know which camera is on air.
The GPI and Tally Interface by Blackmagic Design, is an Ethernet device which provides eight mechanical
relay contact closures to ground that can be used for tally. Tally signals are sent from the Ethernet port of
your ATEM switcher to a GPI and Tally Interface on the same network as the switcher. By following the wiring
guide on the back of the GPI and Tally Interface, a breakout cable can be connected to video equipment
that supports contact closure tally signals, such as Blackmagic SmartView Duo and SmartView HD. Up to
8 tally receiving devices can be supported with a single GPI and Tally Interface. Only one GPI and Tally
Interface unit is needed when used with an ATEM 1 M/E Production Switcher, ATEM Production Studio 4K
models or an ATEM Television Studio. Two units of GPI and Tally Interface are needed when used with the
16 inputs of ATEM 2 M/E Production Switcher.
The GPI inputs are optical isolators which are triggered by connection to ground with a maximum of 5V
at 14mA.
The tally outputs are mechanical relay contact closures to ground with a maximum of 30V at 1A.
The following table illustrates which tally signal is sent when a switcher input is selected on the program
output. When using GPI and Tally Interface with an ATEM 2 M/E Production Switcher, use ATEM Setup
Utility to set one unit to signal on tally outputs 1 - 8 and the second unit to signal on tally outputs 9 - 16.
GPI and Tally Interface
Program Output
Tally signal
Switcher Input 1
Tally 1
Switcher Input 2
Tally 2
Switcher Input 3
Tally 3
Switcher Input 4
Tally 4
Switcher Input 5
Tally 5
Switcher Input 6
Tally 6
Switcher Input 7
Tally 7
Switcher Input 8
Tally 8
Program Output
Tally signal
Switcher Input 9
Tally 9
Switcher Input 10
Tally 10
Switcher Input 11
Tally 11
Switcher Input 12
Tally 12
Switcher Input 13
Tally 13
Switcher Input 14
Tally 14
Switcher Input 15
Tally 15
Switcher Input 16
Tally 16
Using Tally
