Well beside USB, everything works!

Down below is little picture of the test of the rpi_ws281x library...

The only real issue I see with this design is the USB portion.

Maybe I'll opt for a non-chinese usb-hub IC in the next prototype...

Speaking of that - I'll kill that programming USB port... when I did the design, the CM3L was not even announced. Now the CM3L is at the same price-level as the CM1 before (at Farnell) and the CM1 is not really available anymore (huge lead-time). The CM3 is 5€ more expensive and since you can get micro sd-cards for 4€ it makes sense to kick the usb-programmer (some 3€/20 parts on the BOM) and think of an better usb hub...

At least I need to change my ESD protection solution to something more modern... the USB drive you see below is actually an USB 3.0 one and refuses to enumerate on this USB 1.1 protection ICs...

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