Blackmagicdesign Videohub Installation And Operation Manual page 70

Latch Video
If you want the output to stay as selected, choose Latch Video. This means you can press the
switch once on your CCU and the input from the selected crosspoint will stay on your monitor
until another crosspoint is selected.
Select Latch Video if you want your preview to hold until
another crosspoint is selected. Choose Momentary Hold
Video if you want your preview to revert back to the previous
crosspoint when you release the control switch.
Momentary Hold Video
Select this option if you want the output to return to the previous input after you let go of the
switch or joystick control on your CCU. For example, when you press and hold your switch,
Input 13 might be previewed, but will return to displaying Input 12 on your monitor once you
release the switch.
Configuring Tally
Tally is usually a lamp on the front of a camera to indicate that it is on air, but it's a useful visual
indicator and can be used on any equipment to indicate activity and doesn't have to be used
specifically with cameras.
The GPI and Tally Interface has 8 configurable GPOs, which send a tally signal to your cameras
or other devices under certain crosspoint conditions. In the example on the left, GPO 1 is
configured so that when Input 16 on the Videohub is routed to Output 1, GPO 1 will be activated.
The crosspoints can be configured in Videohub Hardware Panel Setup simply by clicking inside
the Input and Output fields on the diagram.
GPO Match
Enable the GPO match checkbox to replicate the configuration of your crosspoints from GPIs to
GPOs. This can be useful if you want to see a tally light activate when changing routes for
your GPIs.
When this checkbox is enabled, the GPO half of the diagram will be grayed out and cannot be
edited until the GPO match checkbox is disabled.
Enable the GPO match checkbox to replicate the
crosspoint configuration of your GPIs.
Daisy Chaining Multiple GPI and Tally Interfaces
The GPI and Tally Interface supports 8 GPIs and 8 GPOs at a time, which should be enough for
most live television situations. However, if you have more than 8 cameras then you may want to
daisy chain a second or third GPI and Tally Interface.
Blackmagic Videohub Software 70