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I think the "transparently shifting the processor between its real and protected modes on the fly" part was referring to how a DOS extender had to switch modes,
by mwcampbell 6y ago
I think the "transparently shifting the processor between its real and protected modes on the fly" part was referring to how a DOS extender had to switch modes, and copy stuff between low and high memory, when calling out to DOS (e.g. INT 21h). It was basically like the switch between user mode and kernel mode in an OS today, except that ironically in this case, it was the "kernel" that was limited in its access to memory.
- throwanem 6y agoI think Jimmy Maher set out to be a historiographer rather than a tech writer. He's damned good at it, too.
- mwcampbell 6y agoHe's definitely a good historian. But, as shown in his book about the Amiga, The Future Was Here, he's also pretty knowledgeable about programming.
- throwanem 6y agoTrue, but a book from MIT Press benefits from considerably more editing ahead of time than a blog post. It's like the mention of network "broadcast packages" in talking about how Doom's netcode destroyed LANs - yeah, I get that it's not technically accurate, but I also know what he's talking about, and that his commenters will catch it and he'll fix it in post.