You need the SDK to be able to create and compile drivers for the hardware, the SDK contains the source code for that.
Every hardware platform is different, even those that appear to be "clones", like the GB Trio 4K and the Octagon SF8008 for example. Identical on the outside and the PCB, and still you can't install GB drivers on the Octagon and v.v.
For every box there is a Yocto BSP layer (board support layer), created by the manufacturer. It contains the machine configuration, and it downloads the binary (so pre-compiled) closed source drivers directly from the manufacturer.
For the Zgemma H9, which is such a box, see https://github.com/O...eta/meta-zgemma.
Currently in use: VU+ Duo 4K (2xFBC S2), VU+ Solo 4K (1xFBC S2), uClan Usytm 4K Ultimate (S2+T2), Octagon SF8008 (S2+T2), Zgemma H9.2H (S2+T2)
Due to my bad health, I will not be very active at times and may be slow to respond. I will not read the forum or PM on a regular basis.
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