How to use the synchronisation input pin of a OV9281 module?

I have a RaspberryPi 4B with OV9281 camera module installed.
OS is bullseye (11). I’m using libcamera.

The OV9281 has a synchronisation input pin. I would like to use it to synchronize it to an external source (an arduino that also flashes IR leds).

How can I do that?
I searched for functions in the lbcamera-dev SDK to be able to do that. But can not find any.
Do I have to change a camera configuration file? I can also not find information about that.

I hope anybody can help me out.


This is an input signal, the flash needs to use a strobe/flash type of output signal.

I think I did not explain very well. In my situation I have an external piece of hardware that generates the flashes plus a sync signal. So I want to connect this sync signal to the sync input of the OV9281.


Our ov9281 is required to have a high level width of 1ms. you cannot connect the flash signal to an external trigger signal.

I will not connect the flash signal itself. I will make sure the signal level and timing is as needed for the OV9281. 3V3 level high for 1ms? No problem.
But how to configure the OV9281 so that it synchronizes on this input pulse?


Can I take a look at your ov9281?
ov9281 has many versions.

I see what you mean, you want to enter the external trigger mode, when the flash input signal, the camera synchronized to take the picture.

This are pictures of the OV9281 we have now:

When we succeed with this project we will need more OV9281 modules. If there are more types, how do we buy the correct one? And is there an other one better suited for this synchronisation?

@Edward , can you please take a look at the pictures above and give me advice how to enable external syncing on these modules?


I’m sorry that I took a long vacation and you can’t use external triggers with this camera.
You can give me your sku number so I can be more sure.


Please wait a moment, there is an untested method that I have to test recently.

I’m here looking for the same thing. The board has the FSTROBE pin broken out which I think it all that’s strictly necessary from a hardware standpoint, no?


Sorry, currently this camera does not work with external triggers, you need to purchase the OV9281 + Pivariety version. If you want to purchase a supported one, you’d better contact [email protected]