simulator, does it not? My recollection is that the only way out of protected mode (back in 286 days) was through a keyboard reset sequence.
That was only on the '286, which required a processor reset to get back into real mode and was assisted by the keyboard controller, one of the Great PC Hacks. It is not as traumatic with '386 and beyond.
Actually that was the kludge to fix it. The *really* savvy way to do it was a triple fault. Something along the lines (going from memory here) like trashing the stack and executing an illegal instruction. The processor would take exception to the illegal instruction (fault 1), go to push CS,IP,F to the stack, which wasn't there (fault 2), cause exception to that and go to push them again (fault 3) so it would reset. Thousands of times faster than playing with the keyboard controller to hit reset.
That's all from memory so it may be a little incorrect, but the theory is sound. It may have been only a double fault, but either way that method was MUCH faster than resetting through the keyboard controller.
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