How can I send triggers from MATLAB via the USB virtual serial port trigger cable provided with my ActiveTwo System?

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:

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