The video synchronization port provides an input to the Expert3D board used to provide a periodic signal to which the display system attempts to lock its vertical refresh rate. This port uses a 75 ohm BNC male connector. A 75 ohm coax cable terminated with a female BNC connector is needed to connect to this port.
The video synchronization port supports the following formats:
NTSC composite video
PAL composite video
TTL, LVTTL, or CMOS-level compatible signal (50 Hz to 180 Hz), with a minimum low or high pulse of 100 nS (TBV)