Stereo sync

[Andrew Certain]

In article <1990Nov30.172515.26299 at ecf.utoronto.ca> xiaoyan at ecf.toronto.edu (Yan Xiao) writes:
>
>	What we do is to show two dots at lower corner of the screen, each
>	one of them representing one field. To control the spectacles, we
>	read these two dots via a light-sensor and a circuit.  It sounds not
>	so smart, but the setup has been working just fine.
>
>	We got a new monitor with a sync port at the back but no clue how to
>	use that port.
>
>xiao

We have a passive-glass system, so that there is a plate that we put in front
of the monitor which polarizes the light coming from the screen, switching
directions at 60Hz.  The glasses are just polarized lenses so that each eye
only gets light every other cycle.  So I need to know when the buffers have
swapped (and, hence, the plate has flipped eyes), so that I can start drawing
the other eye.

Andrew