RVC2 PPS signal reception and generation.

Huimin

Hi Luxonis Team,

I would like to utilise the real time processor onboard RVC2 through script. The use case is that RVC2 is able to receive a GPIO pulse-per-second signal, and without time jitter, faithfully record the time it saw the pulse. Also at the same time, I would like the same GPIO pin to be able to be configured as the PPS output, namely outputing a pulse precisely every 1 second, and the full second of the internal clock ideally.

Is this something achievable with Depthai API right now? If yes, what is the recommendation for GPIO pin and the code example?

Thanks in advance!

jakaskerl

Hi Huimin
The accuracy you are looking for is not supported inside the script node. Perhaps you could utilize the hardware FSYNC (https://docs.luxonis.com/projects/hardware/en/latest/pages/guides/sync_frames/)?

Thanks,
Jaka

Huimin

Hi jakaskerl

Thanks for clarifying! However may I know the accuracy it does support? Particularly the callback API for timestamping GPIO inputs?

Thanks!

erik

Hi @Huimin ,
Script node runs python interpretter in subprocess - it's far from realtime. Easy way to test (which we haven't done) is to toggle GPIO every 1sec (time.sleep(1)), and check on the scope the actual frequency it produces. I'm fairly sure it wouldn't be able to achieve +-1ms time accuracy.
WHy is PPS required in your case? To sync clock? As clock is already synced by default with the host computer.