While I was testing the software a package with the MLX90642 and the PCBs arrived. I quickly populated all the parts and started programming the same software I made for my dev board to the unit. Microcontroller was starting up, USB connection was recognized by my PC and nothing happened on the screen.

So I started debugging the connections and everything looked fine. After some headbanging I finally figured out the issue. The Aliexpress seller had the pin numbering mirrored. So 1 2 3 4 5 6 became 6 5 4 3 2 1 and I flipped the connections. I thought I double checked this on the board with the display but I forgot that the Aliexpress board has the cables folded over. So there goes the display and touchscreen support.

While I couldnt use the screen I was able to test some of the other features like the USB webcam support.

And I was able to test the SD card support. It writes both a BMP and a RAW file with the temperatures to the disk. That way I can decode the actual temperature later down the road.