There's a well-known pattern: if a device has any processing power, no matter how small, it will surely receive a DOOM port. Today it's the turn of an Apple-made Lightning-HDMI adapter. The demo doesn't seem to have sound, and there's no way to connect a keyboard or a mouse, but the real question is: why is there so much silicon inside a dongle…?
If memory serves me right, I'm already on my third active adapter to generate a VGA signal. The first two converted an HDMI signal, but they ended up throwing in the towel in a few months. The last one I bought converts DisplayPort to VGA, and it has held up quite well so far. When you open these adapters you don't find much inside: a chip of dubious origin, wires soldered with questionable quality, a good dose of glue, and a couple of screws (if you're lucky). Now, I would never have imagined that someone could install DOOM on a dongle… but Apple always does things differently, and its Lightning-HDMI adapter has a surprise:
Running DOOM on an Apple Lightning-HDMI dongle
«Nyan Satan» explains on his YouTube channel that the adapter has an SoC with a minimalist version of iOS. The software includes SecureROM, iBoot, and an XNU kernel, but it doesn't even load a filesystem. The only advantage is a ramdisk (there's no persistent storage), and that's why we see the Mac loading firmware into the adapter. Everything that appears in the terminals is the UART output (iBoot, kernel, and userspace). How did it get past security? With the famous checkm8 exploit.
Another user notes that Apple needs to use this hardware because of Lightning bandwidth limitations, equivalent to USB 2.0. The information enters the dongle compressed, and the SoC's job is to decompress and convert to HDMI. Obviously, there's still work to do: there's no audio (what we hear is The Demon's Dead from DOOM 2), and you can't play due to lack of controls, but I imagine it's only a matter of time…
Source: MacRumors
