I watched a little of both, but they're really a very low level view of things. The PS/2 interface over USB is almost a kludge just to maintain some compatibility. It's very, very simple.

The device discovery video covers a little more, but stays almost entirely within the basic "Hi, who are you" section of the protocol.

The HMI protocol page which he's showing is about as low in the protocol as one can get and still function, apart from that PS/2 interface over USB.

There's lots more.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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