# Concurrent Use of Two PMD TOF Sensors

Source: https://forum.modalai.com/topic/411/concurrent-use-of-two-pmd-tof-sensors
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: voxl
Posted: 2021-08-23 05:39:44 UTC by aronhadad
Replies: 2 · Views: 1007

## aronhadad · 2021-08-23 05:39:44 UTC

Hi,

Can the VOXL be configured to interface two PMD TOF sensors concurrently?

Kind Regards,
Aron

## Reply by Guest · 2021-08-23 15:37:38 UTC

The VOXL board can handle multiple TOF sensors, but this is not a configuration that we support with voxl-camera-server. It would be possible to have custom processes running that fetch data from the specific ports. If you wanted to try this you could look through the deprecated [hal3-tof-cam-ros](https://gitlab.com/voxl-public/old-projects/voxl-hal3-tof-cam-ros/-/blob/master/source/src/hello_hal3_camera_mgr.cpp) project for how to fetch image data from hal3 and send it to the royale/spectre libs for processing.

## Reply by Alex Kushleyev (ModalAI staff) · 2021-08-25 03:06:10 UTC

Actually, I don't think it's possible because two identical PMD sensors will have the same I2C ids and communication will interfere. All cameras, with the exception of right stereo (if stereo flex is used) are communicating on the same (primary) i2c bus. The right stereo camera uses the secondary i2c bus. If it were possible to change the I2C id of the PMD sensor, then it could work, but I am not sure if that's an option.