Voxl - Snapdragon model and supported camera configurations

[rgsmith]

Hi,

I'm trying to find some more detail on a few Voxl specs.

• The overview here specifies that the Voxl uses a Snapdragon 821, but the links point at a Snapdragon 820E. Do both these identifiers refer to the same Snapdragon?
• I'm interested in setting up a camera configuration that is not listed here. I would like to use two stereo pairs + one HiRes - is such a configuration possible? I still don't have a strong understanding of what the MIPI CSI physical layer or Qualcomm Spectra Image Signal Processor can support.
  • This might not be the right Qualcomm Spectra ISP, but it seems to imply that only three simultaneous cameras can be used. Given that the voxel supports a HiRes + Stereo + Tracking configuration though, does that mean something special is going on with the two stereo cameras?

Many thanks!
~Russ

[Chad Sweet]

The Snapdragon 821 is a speed grade version of Snapdragon 820. The Snapdragon 820E was the version Qualcomm sent to distribution, they're all fundamentally the same. Maybe +/- 5% on max clock speeds

The MIPI-CSI configuration for stereo is a special use case, only supported on a few Qualcomm robotics chipsets. It is not very flexible and only works in the configurations we advertise as supported.

[rgsmith]

Hey Chad,

Perfect thanks, thats exactly what I was looking for regarding the Snapdragon model.

So if I understand correctly, the specialized stereo configuration is a hardware limitation inherent to the Snapdragon? I'm trying to understand if this is a case of 'Qualcomm only supports this configuration' or 'ModalAI only supports this configuration'. Your comment leads me to believe that the former is true, and ModalAI's supported configurations are a result of Qualcomm limitations. I just want to be totally sure I've understood your comment correctly, can you confirm that?

Thanks,
~Russ

[Chad Sweet]

Your understanding is correct, ModalAI's supported configurations are a result of Qualcomm limitations