External trigger and solder point docs for ArduCam OV9281 Jetvariety UC 788 rev. B

Raspberry Pi Cameras
1

Hi, I’m using an Arducam OV9281 Jetvariety UC 788 rev. B and I’m trying to figure out the solder points on the board. There are several pads labeled 3v3, siod, sioc, fstrobe, gpo, xvs and gnd. I can’t find any documentation that explains what each one does or which one I should use. My main question is: where do I connect an external trigger signal? Any pointer to the right docs would be great.

2

Hi, thanks for reaching out. The OV9281 Jetvariety UC 788 rev. B doesn’t have a dedicated datasheet for the solder pads, but the external trigger camera application note for the MIPI camera modules on Jetson Nano covers the trigger wiring and generally explains those points. Have a look at this guide:

https://www.arducam.com/docs/camera-for-jetson-nano/mipi-camera-modules-for-jetson-nano/external-trigger-camera-application-note/

Give it a read and let me know if anything on your board still doesn’t line up with what’s shown there.

3

Thanks, I’ve had a look at that page. It’s helpful for understanding the overall trigger setup, but I’m still not 100% sure which of the pads on my specific board is actually the input for the external trigger. You mention the trigger wiring but I want to be sure before I solder anything to the wrong pad. Could you confirm which point the trigger signal should go to?

4

Right, to clarify: the external trigger signal needs to be connected to the fstrobe point on the board. That’s the pad that accepts the incoming trigger.

So for your OV9281 Jetvariety UC 788 rev. B, wire your trigger signal to fstrobe (and make sure your ground is tied to gnd). The rest of the pads (3v3, siod, sioc, gpo, xvs, gnd) are the standard supply and I2C/sync lines, but fstrobe is the one you care about for the external trigger.

If you want the background on how the trigger is expected to behave, the guide here is the official reference:
https://www.arducam.com/docs/camera-for-jetson-nano/mipi-camera-modules-for-jetson-nano/external-trigger-camera-application-note/

5

Perfect, that’s exactly what I needed. So fstrobe is the trigger input, and gnd for ground. I’ll wire it up that way and check the application note again for the signal behavior. Thanks for the quick help!