[Elphel-support] General discussion about trigging

[jeff witz]

Dear Elphel developpers,

We have several cameras that works well for almost all our goals, but
there is one issue that causes real interrogations. For a majority of
our vision applications it is important to be able to master perfectly
the time when a frame is made. Of course we know the process that
allows one to trig the camera by internal or external trigger. But we
think that there is an issue that must be treated in order to allows
us to use our cameras in he best conditions. The problem comes from
the the way the trigger is made, indeed, if we set external trigger
then if we wait over a sensor idle time, the camera looses the
synchronization with the sensor. In our applications the trig of a
frame depends of "physical" events which are not periodic. So we
really need to have an external trigger which is able for example to
wait 20s. then trig 10 in  1s. then wait a min. Of course we can
achieve this by the arduino trig version that Alexandre made, but the
timestamp really matter for us.

Do you have any Idea that allows us to reach this goal.

Best regards.