Software update just pushed me an update for my mini display port to VGA adapter. Yes really. 11mb too. I've never seen an adapter get updated before. But considering the physical size of the adapter, I am assuming the mini display port is actually just a micro DVI port, and has no vga, so it requires active electronics to make VGA. (it's more of a converter than an adapter)
I work for the Department of Redundancy Department
DisplayPort is not DVI, it's much more advanced, but it is similarly digital while VGA is analog. So yes, the adapter converts the signal from digital to analog, and as such has firmware. (Not that I've ever seen an adapter get a firmware update either... )
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