Frame Sync Between Cameras


I am seeking to make a project that captures a still photo from 2 to 4 cameras at the same time in complete frame sync.

Is there a way to share clock among multiple cameras and capture at the same time using the same settings?

Thank you for any advice you can offer!

Yes, it’s kinda janky however and only works for the OV7725 camera (the OpenMV Cam H7).

You need to connect the FSYNC input on the camera to a master clock source that runs at 60/120 Hz. The PLL inside the camera will sync up to that for frame output.

The clock should be like 60 Hz for VGA and 120 Hz for QVGA or less.

Awesome, thanks!

Does FSYNC also works for OpenMV Cam M7 which adopts the same OV7725 ?
I notice, from the Cam M7 schematic, the FSIN pin is pulled to GND thru a 10k resistor, while for Cam H7, there is no such design, is there any specific concern for Cam M7?

FSYNC on the OV7725 doesn’t really trigger the camera. It just kinda syncs up the camera’s VSYNC to it. It’s not really usable honestly.

For future products this will become a proper trigger input/output.