On (01 Jul 97) Craig Hart wrote to Herman Schonfeld...
 > The 286 (technically referred to as the 80286)
 > processor was the first in the Intel family to introduce separate
 > operating modes. The architectural features of Protected Mode
 > included larger physical memory, better memory management, and
 > hardware support for multi-tasking and task-switching operations.
 CH> AFAIK the 80386 was the first processor to introduce hardware support
 CH> for multi-tasking and task-switching. Care to say how the '286
 CH> implements this so-called 'hardware support'?
Oddly enough, while Herman is incorrect about how to refer to a 286
(according to Intel, it's supposed to be referred to as the "iAPX286",
and "80286" is only a part number) he's right about the hardware support
for task switching and multitasking.  The 386 basically only added two
things to what the 286 already had - first was the added ability to
define and work with USE32 segments - e.g. a new TSS structure that held
32 bit registers instead of 16 bit registers.
The other obvious addition in this area was V86 mode, which makes
multitasking of real mode applications relatively reasonable.
    Later,
    Jerry.
... The Universe is a figment of its own imagination.
--- PPoint 1.90
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