Brickcom NVR have the built-in 4 digital inputs and built-in 2 digital outputs, which can be set for triggered-events.

DI/DO connect sockets can be found in the rear panel of Brickcom NVR. 

The definition of DI/DOis as below:

• The pin connection of digital input.

           GND pin should be connected to any one of DI1 to DI4.

• The pin connection of digital input.

           Vcc5V pin should be connected to any one of DO1 and DO2.