EEG HD1430 Product Manual page 32

The first connector is labeled GPO1-4:
The second connector is labeled GPO5-8:
The two pins of a given GPO form a switch that is on when closed and off
when open. For example, pins 1 and 2 of the connector labeled GPO5-8
form a switch that is closed when GPO 5 is active, and open when it is
inactive.
HD1430 HD Encoder Frame Card
GPO Pins
4 7, 8
3 5, 6
2 3, 4
1 1, 2
GPO Pins
8 7, 8
7 5, 6
6 3, 4
5 1, 2
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