Running multiple Bolts synchronized with external trigger

[HunorLaczko]

Hi,

I'm trying to set up 8 Femto Bolt devices to do synchronous capture, but triggered from an external source (raspberry pico).

I have connected the pico to one of the Bolts, through its VSYNC_IN and GND pins, this Bolt is connected to the Sync Hub Pro's master port (with the other 6 pins, since VSYNC_IN and GND is taken by the pico). It has the "trigger out" pin enabled. I have the other 7 Bolts connected to the Sync Hub Pro with the official adapter cables as slaves. I tried to disable the "trigger out" function, but it didn't work. I have set up the delays as well in the MultiDeviceSyncConfig.json file. All 8 devices are configured in OB_MULTI_DEVICE_SYNC_MODE_SECONDARY mode. I'm working with a modified version of the MultiDeviceSync example, where I start all the cameras, and sleep for 10 seconds then stop the devices. During this I start the external signal on the pico. I had this working at one point, but then changed something and couldn't get it to work after.

Could you tell me if this is the right approach to what I want to do?

Thank you!

[zhonghong322]

1、Please refer to this document: Synchronize Multiple Femto Bolt Devices. ( https://www.orbbec.com/documentation/synchronize-multiple-femto-bolt-devices/?_gl=1*kx5vck*_up*MQ..*_ga*MTEzODE2NzM1Ni4xNzI1MDE0MDUx*_ga_9WLYL9TPFD*MTcyNTAxNDA0OS4xLjEuMTcyNTAxNDA1Ni41My4wLjA. )

Using External Trigger:
In both configurations, the master device provides the trigger signal to subordinates. But you can use a custom external source as the sync trigger instead. For example, this option can enable syncing captures with other equipment. The external trigger source connects to the VSYNC_IN port on devices.

The external trigger source must operate the same as the master device. It must provide a sync signal with:

Rising edge trigger
High pulse width: >1ms
Trigger level: 1.8V/3.3V/5V
Frequency support: exactly 30FPS, 25FPS, 15FPS and 5FPS (the frequency of the master camera’s VSYNC_IN signal)
The trigger source must use a Multi-camera Sync Cable to relay the signal to the sync signal input port on subordinates.

2. External Trigger Wiring Diagram：