Presence of leakage voltage in D435 series during hardware triggering

Hi Intel family,

I am currently trying to hardware trigger 3 realsense cameras (D435, D435if, and D455f) simultaneously. I am using the 9 pin connector intended for the realsense cameras and using Sync pin 5 and GND 9 for the connections. When I provide a trigger pulse using a push button with a 3.3V/5V logic converter, the exposure starts normally in all 3 of them. The next exposure starts again for the next trigger, which is as expected. But, when I provide a train of pulses using a different trigger source, for ex: from a raspberry pi GPIO, I see a strange behavior. The trigger starts when I start the pulse generation program and it stops only in case of D455f, but for D435 and D435if it does not. However, I managed to notice that there is a leakage voltage that makes the GPIO pin to stay high even after stopping the pulse generation This could be because of the GPIO pin staying high when it is stopped, but not sure. But, my doubt is D455f is successfully able to detect the time at which the pulse stops but D435 and D435if fails to do it. So, may I get a better clarification on why such a behavior is seen? It would be of great help if you can explain on how the circuits are interfaced with the 9 pin connector for these models and if adding additional circuit to divert this to GND might help.

Thank you in advance.

Best regards

Madhu Dhanasekaran