1 Jun
2014
1 Jun
'14
12:25 p.m.
> [...]. 80186/80286 dual-CPU machine, [...].
Completely and utterly
> different hardware--was constructed to run Xenix for the 80286, with
> the 80186 doing I/O work. I can't think of a single PC-compatible
> compatible aspect.
On Sun, 1 Jun 2014, Mouse wrote:
The 80286 and 80186 were actually used in IBM PCs of
various
generations, were they not?
I can't recall any model from IBM that used an 80186.
If so, the basic instruction set would be
a PC-compatible aspect, would it not?
Yes, 80186 and 80286 were completely
PC-Compatible.
There were plenty of PC-Compatible machines that used them.
But, there was a LOT more than processor needed to be compatible with PC
software.
For example, although MS-DOS had OS calls to write characters to the
screen, virtually all commercial software ignored them, and wrote directly
to video memory. That made it pretty easy to build an MS-DOS machine that
couldn't run software sold for the PC.
--
Grumpy Ol' Fred cisin at xenosoft.com