PM>>> 8086 isn't a PC processor ;-)
SM>>> Sure it is.  It just wasn't seen all that often.
...
PM>> Don't think its opcodes are compatible with other 80x86es.
SM> Sorry.. these are wrong and wrong, respectively.
SM> There were many 8086-based machines, but were not popular
SM> relative to the 88 systems because they required 16-bit 
SM> interface cards in a day when the 16-bit interface card 
SM> was somewhat rare, and relatively expensive.
Dayrrl Gregorash (and friends) are correct.  From the perspective of 
software, the 8088 and 8086 are identical.  The hardware difference of 8 bit 
vs 16 bit is also correct.  Furthermore IBM did make some 8086 based 
machines.  The first I saw were some of the original PS/2 computers.  Some 
were 8088 based, some were 8086, and some were 80286.  This is when the 
computer lines used model numbers that had no easy way to identify the 
interior hardware.  This is also when finance people took over the IBM PC 
computer line.  Some original PS/2s used the Microchannel - others did not.  
Total confusion.
The 80186 was first proposed for the PC Jr.  It should have been an ideal 
chip for this machine, but, as I understand it, there was a minor programming 
difference between the 80186 and the 8086 series chips.  Therefore the PC,Jr, 
in a myopic attempt to make it less competitive to the PC, was an 8088 with 
the Chiclets keyboard, etc.
  Also what was proposed by product oriented thinkers at IBM was an 80286 
that could shift into and return from Real to Protected mode.  Again those 
myopic finance people killed that too.
  The 8 bit verse 16 bit interface was the source of so many Intel ads in 
those days that showed a man attempting to assemble a tricycle with parts 
missing.  This was a direct snub at the 68000 line which suffered even more 
so from a shortage of 16 bit interface chips.  To solve its 16 bit interface 
problem, Motorola signed numerious chip making competitors who were expected 
to develop 16 bit interface chips in exchange for the manufacturing masks and 
test vectors for the 68000.  Intel did the same thing with less vendors.  Two 
are noteworthy since Intel's partner Harris pioneered CMOS technology and 
power down modes in the Intel system.  Intel was then using NMOS technology.  
Another Intel partner, AMD, made only one Intel interface chip - the DMA 
controller found in the original PC designs.  AMD simply claimed that one 
chip was all they needed to have the rights to manufacture Intel chips.  
There is the foundation of the AMD-Intel wars.
  But since there were few 16 bit interface chips, it did not make much sense 
to use the 8086 in the original PC.  That is why we are so familiar with the 
8088 - a variation of the orignal 8086.
--- Maximus 3.01
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