Since mid-2016, Biosemi has included a black USB virtual serial port trigger cable with each new ActiveTwo system. The device is depicted below.
Inside the shell of the 37 pin connector is a microchip that appears to the stimulus computer as a virtual serial port but provides 8 bit parallel TTL output to the ActiveTwo trigger input port. Because it appears as a virtual serial port on the stimulus computer, this cable is a relatively universal solution for triggering ActiveTwo from virtually any software on any platform. There are a few simple parameters you need to know to send triggers via this device. For details, see:
To use this trigger cable with MATLAB, Roee Gilron at UCSF (thanks, Roee!) provides a code sample at Github: