Using tCam-Mini Hardware Interface to simply Lepton on Pi

[Dan Julio]

Here is another way to connect a Lepton 3.0 or 3.5 to a Raspberry Pi that obviates some of the performance issues when trying to read the VoSPI directly.

Starting with the Rev 4 PCB design, my tCam-Mini design is now sporting a hardware interface that allows connecting it up directly to another controller such as the Raspberry Pi using a dual serial/SPI interface.  Unlike talking to the Lepton directly however, the tCam-Mini manages the VoSPI and the Pi communicates with tCam-Mini using its high level json packet interface using the SPI interface to get each image when necessary.  No need to maintain a high speed sync with the Lepton.

We ported the python driver for tCam-Mini to support the hardware interface on the Raspberry Pi.  The driver provides high level commands for getting the raw radiometric data from the Lepton and for controlling the camera.  From there it is easy to use python to create images and there are demos showing various ways.

You can read about tCam-Mini here: https://github.com/danjulio/lepton/tree/master/ESP32/tCam-Mini

You can read about the Python driver here: https://github.com/danjulio/lepton/tree/master/ESP32/python.  That page shows how to wire tCam-Mini to the Pi and there's example code (streamtest_hw.py) that displays a streaming image on the Pi desktop.

And you can buy tCam-Mini from group gets here: https://store.groupgets.com/products/tcam-mini-rev4-wireless-streaming-thermal-camera-board (or build your own as the design is open source).

Of course you can also talk to tCam-Mini via WiFi using the same python driver from any computer.

Please let me know if you have any questions and I'll try to answer.