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palmotea • last Thursday at 5:23 PM • 1 reply • view on HN

> The ARM Core starts up, does crypto, Loads the SecureOS and the BIOS, then it starts the x86 CPU - In 16 bit mode! Which then boostraps itself through 32 then 64 bit mode.

Well, what if I want to run a 16-bit OS?

Also, I wonder if the transistor count of a literal entire 8086 processor is so small relative to the total that they just do that.

According to https://en.wikipedia.org/wiki/Transistor_count#Microprocesso...:

    1978 Intel 8086:         29,000

    2021 Rocket Lake: 6,000,000,000
So you could fit 200,000+ 8086s on that not-so-cutting-edge silicon.

Replies

immibis • last Thursday at 7:46 PM

You should use a 16-bit CPU then, or an emulator.

Compatibility mode doesn't work by having a separate 16-bit core. It's random bits of spaghetti logic to make the core work like a 16-bit core when the 32-bit flag isn't set.