[Elphel-support] camera triggering

[Andrey Filippov]

> If several cameras are synchronized together, and TRIG_DELAY is set to 0, what front of the TRIG_BITLENGTH is used to trigger the sensors ? The beginning or the end ?

Beginning. But actually that does not matter much, because the
"master" camera is triggered from the same pulse as all the other
ones. You remember that the cable connects input and output on that
camera.



> Now what if I would like to use 10 cameras and film in FullHD @ 25 FPS with each camera, but in triggered mode and delayed so that final result would be  250 FPS frames. As I understood TRIG_DELAY will force all slave cameras to have the same delay.

Master camera also. You may consider trigger source as a separate
device from the camera where it is installed.

> I also noticed that while the camera is not triggering (during the boot  sequence) the LED attached to J15 connector of the master camera is always  on. As soon as the sensor is configured the led start to blink from trigger.

That is wrong, it should be off. Will need to check - why is it so. Is
it on all cameras?

> The question is can I use this port in free-running mode to power an  external 2,5" SATA hard drive ?

No, you can not. If the camera had enough power we would already use
it for that purpose. But it does not.

Andrey